Look at my ring and pinion set up pattern -- close?

[Stranger in the Black Sedan]

Hi guys, I have been very busy pressing and shimming to set up my new gears. They are genuine brand new Ford OEM gear whine replacement 5L3Z-4209-B 3.55 gears (not the cheaper Ford motorsports) gears. I have tried 0.022, 0.028, 0.032, 0.037, and 0.042 pinion shims. The 0.042 gives the best pattern I think I can get, centering the pattern from flank to root on the gear -- maybe it is a little too deep towards the root? The 0.037 pattern, although it looks good at first glance, notice is too close to the flank (tip) of the gear -- indicating the pinion shim is too thin (shallow). Should I try 0.040"? My #1 concern is that the gears be QUIET. If you look at the side views of the 0.042 shimmed pattern, it looks like I did a pretty good job of getting the pattern centered from root to flank. However the contact patch is not a nice oval, it has sort of a weird shape, which is a little heavy towards the root of the gear as it progresses towards the heel. There is no way for me to get a better contact than this, it's just the way these gears and the housing are going to be.

PS, the backlash with the 0.037 shim is 0.011" and the backlash is 0.009" with the 0.042 pinion shim (both within the 0.08 to 0.013 range). I can not fine tune the backlash any further than this, because the thinnest carrier shims I have are 0.010".

http://www84.homepage.villanova.edu/steven.hylinski/gearsetup.html

Thanks guys!

[JMan]

Dude,
What on earth did you take those pictures with? It must be the university's electron microscope. It is very hard to judge the contact patch from a picture. In the earlier pics, it looks like the pinion depth is too deep (way). But those last two pics, despite not being able to tell any orientation due to their closeness, it (pinion depth) looks dead on. Do tell what you took those pictures with!

Best luck,

J

[Stranger in the Black Sedan]

The pictures marked "0.037" are less deep than the 0.042 pics, so the pictures towards the bottom are actually deeper. I took the pictures with a Canon A540 regular digital camera. If you take pics further away than that the pattern doesn't show up at all. If I use much less than 0.037" pinion shims, there is no "head room" at all between the highest part of the pattern and the flank (tip) of the gear, which tells me it's too shallow.

[TooManyFords]

There is a quick and easy way to determine what the pinion shim should on a Ford 8.8. Since the housing is machined to an exact tolerance, the setup is relative to the thickness of the pinion gear face (the part that you see from the open cover side).

Here's how it works:

Pull the existing pinion gear and measure the width of thickness of the gear, face to bearing side and write it down.

Measure the same dimension of the NEW pinion gear.

The difference is applied to the thickness of the existing pinion gear shims.

If the new pinion is +.002 thick compared to the original pinion gear, then subtract .002 from the shim pack. If the new pinion gear is thinner, then add the difference to the shim pack.

Press the bearing on with the new shim pack, set the preload and then you're ready to put the carrier back in.

Start witht the shims where they were and torque to 77ftbl. and check the pattern. if you feel you need to adjust then do so to get the correct pattern.

Button it up and break them in per manufactures specs.

Done.

john

[Zack]

Or take it to a professional, like I do

[TooManyFords]

Or take it to a professional, like I do

See, now that surprises me. You'll take an engine apart but can't put two gears together...

Learn something new everytday!

John

[Zack]

See, now that surprises me. You'll take an engine apart but can't put two gears together...

Learn something new everytday!

John

Knowing your limits is a virtue most DONT possess :D

[Stranger in the Black Sedan]

John, my factory gears were adjusted by the dealer, and were very noisy. I have no reference starting point. I know the nominal pinion shim for an 8,8 is 0.030. The old OEM gear was marked "-2" and had an 0.028 shim. The new OEM gear is marked "7", which would dicated 0.037". My 0.037 pattern was not terrible. I am going to shim it deep, to maybe around 0.046, and see what it looks like. If the pattern is still getting worse I think I am going to set it at 0.040" and button it up.

Taking it to a "professional" is what caused the factory gears to be so loud in the first place. The dealer took slightly noisy gears, adjusted them, and made them howl. I don't trust anyone enough to not do it myself.

[04MEMA]

A guy I work with knows a thing or two about these things - here's his reply to your issue:

"His pattern is Low, both .037 and .042 is way too much pinion shim. I would advise starting with the original shim that came in the axle and .010 backlash or
around a .030 pinion shim and .010 -.012 backlash"

Hope this helps,
Jeff

[Stranger in the Black Sedan]

The pattern was almost off the gears at 0.030, I already tried that, not even close. It was so high on the tip of the gears, both on the drive and coast sides, that it almost was not touching. I would have destroyed the gears driving on them set up like that. The stock shim was 0.028 and the pattern was also so high it was almost off the tip of the new gears. I guess I am just going to have to go with my gut and put it together. I appreciate your effort though!

I agree it is low with the 0.042 shim. With the 0.037 shim I think it is as good as I can get it, centering root to tip.

[magindat]

Knowing your limits is a virtue most DONT possess :D

Nine hundred million bajillion bonus points for that statement.... :beer:

[KillJoy]

Nine hundred million bajillion bonus points for that statement.... :beer:


You have a voice mail ;)

KillJoy

[Stranger in the Black Sedan]

Knowing your limits is a virtue most DONT possess
Setting up gears shouldn't be a limit anyone with the tools and the time can't overcome (at least I should hope not!). Gotta have a "first time" for everything. Hopefully my "first time" doesn't give me really loud gears. I'll be the first to let everyone know if I'm an idiot and it does. I'd rather screw up my own car and know what I did wrong, than have someone else (ie the DEALER) screw it up for me, charge me for screwing it up, and then I still don't know what went wrong.

Steve!

[SilverSport]

Changing pinion depth on gears that are already broken in to get rid of noise will not work. I'm surprised a dealer would reshim and not install new gears under warranty, Anyway, I agree with you on the "37" shim, looks like the best pattern and the backlash is good. Setting up gears is not that hard as long as you do your homework and have the proper tools. It sounds like you have both bases covered, so button that sucker up and get some lube in there. I usually break gears in with dino lube and switch to synthetic after 1000 miles or so. Don't know if it helps much, but I never had a set go bad. Good luck, and go easy for awhile.

[Stranger in the Black Sedan]

Silversport, yes I told the dealer they could not and should not try to adjust my factory gears since they had a wear pattern on them. However, of course they thought they knew better than me since I'm "just the customer". Frieking idiots. They wasted DAYS jacking around with used gears and made them so much worse than they were before they touched them. Thanks for taking the time to look at my progress.

[Local Boy]

I've been told not to use convetional oil in the diff., because there is really no break in period; but start right off with full synthetic oil. Reason given, (makes sense to me) is that the diff. tolerences are specific/close and you don't want it to change (ie:get larger) or noise will present itself. It's not the same as a motor, where you have rings and other components that need to "seat" themselves. What's your thoughts? I really enjoy the learning aspect of this great site! ALOHA

BTW: You (Silversport) probably never had a set go bad, because you knew what you were doing, and did it right the first time.

[Stranger in the Black Sedan]

I am going to do a first fill w/ the Mobil 1 75-140 and FMS modifier. They don't make a wide blend 75-140 conventional from what I've found (85-140 yes).

[Local Boy]

Forgot to wish you luck with the install - ALOHA

[Stranger in the Black Sedan]

Yes! With all this luck on my side maybe the gears won't howl. :banana:

[Blackened300a]

http://www84.homepage.villanova.edu/steven.hylinski/37_1.jpg

That looks like the same pattern I had on my ring. Hope its quiet.

[Stranger in the Black Sedan]

Here is an updated copy of my pattern pics. I have now included 0.022, 0.028, 0.032, 0.037, and 0.042 shim patterns. You can see how bad the pattern started out. The 0.028/0.032 pics look "better" as far as the pattern being more oval shaped, BUT notice how they are right up to the tip of the gear -- this is not good. It looks like I am going to have to settle for a less than perfect shape, but centered properly on the gear, than a broad diffuse pattern that is too shallow.

http://www84.homepage.villanova.edu/steven.hylinski/gearsetup.html

[1stMerc]

Here is an updated copy of my pattern pics. I have now included 0.022, 0.028, 0.032, 0.037, and 0.042 shim patterns. You can see how bad the pattern started out. The 0.028/0.032 pics look "better" as far as the pattern being more oval shaped, BUT notice how they are right up to the tip of the gear -- this is not good. It looks like I am going to have to settle for a less than perfect shape, but centered properly on the gear, than a broad diffuse pattern that is too shallow.

http://www84.homepage.villanova.edu/steven.hylinski/gearsetup.html

Keep the info coming. I'm contemplating doing my own if i can't find a shop around here.

[Stranger in the Black Sedan]

Ok guys I got the skinny from Jeff, it looks like my 0.028-0.032 range is the sweet spot and I have just not been applying enough load on the gears to get a readable pattern. Car should be together tonight, hope for the best. I was told the "oval" patterns people get with face milled gears will not look anything like the patterns I will get with the OEM face hobbed gears. Basically the patterns I was looking at for examples were from people setting up aftermarket gears, which do not really compare to the patterns the OE gears Ford is using will give. Super duper!

Thank you Jeff for keeping me from doing something stupid!

Steve

[TooManyFords]

I would have liked to see a .035 shim pattern... (.028 + .007)

John

[Stranger in the Black Sedan]

John, I am going to run a few more patterns before I install. But, basically I was told that OE ford gears should fall +/-2 from nominal and that I shouldn't have to shim outside this range. The housing is probably not dead on perfect but it is probably not far off either. My 37+ shimming was mistaken based on my expecting the pattern to look more like an oval, like some aftermarket gears, instead of the blocky square pattern on these when they are set up close.

[magindat]

In general, dino is used for break-in due to carbon content. It gives the metal some carbon to grab while it reaches it's final crystal matrix through heat cycling.

Don't know how much that matters for gears, but engines need dino first, then synthetic after break in.

[Stranger in the Black Sedan]

Ok here is the pattern at 0.030. After some guidance from Jeff he realized I was too deep w/ the shims, and I was not loading the gears enough. I corrected both of those problems and here we are

http://homepage.villanova.edu/steven.hylinski/finalgears.htm

A lot better!!!!!

[cyclopsram]

Who cares if they are loud... if they are set correctly and last... It is interesting that in the Ford Fleet brochure, they indicate that the Police gears and tranny are much more noisy than the consumer version and it is not a problem... Freaking is the spelling after " freak"...who knows what frieking is. Maybe it has something to do with gear noise...

[Stranger in the Black Sedan]

Who cares if they are loud... if they are set correctly and last... It is interesting that in the Ford Fleet brochure, they indicate that the Police gears and tranny are much more noisy than the consumer version and it is not a problem... Freaking is the spelling after " freak"...who knows what frieking is. Maybe it has something to do with gear noise...Are you for real? If you don't have something constructive to add, then please don't add it. I CARE IF THEY ARE LOUD. A $35,000 CAR SHOULD NOT HAVE LOUD GEARS AT THE STOCK RATIO. Jeez. This is my tech post about a real issue. I won't even bother re-explaining it though. By the way, correctly set up gears (which will NOT whine at the 3.55 ratio) will also be the strongest, since the load will be spread out across the gear in a good distribution, at the correct location. I am going to have nice quiet gears now that the pattern is set up right. I am very grateful for the people on this board who have contacted me and given me constructive advice, which fruitfully led me to set the pattern up correctly on my own.

I have put a lot of time and effort into making my car better for me. I really could do without a "who cares".

[JMan]

Ok here is the pattern at 0.030. After some guidance from Jeff he realized I was too deep w/ the shims, and I was not loading the gears enough. I corrected both of those problems and here we are

http://homepage.villanova.edu/steven.hylinski/finalgears.htm

A lot better!!!!!

Those final pics look excellent. Please report back to us with the results. I do believe you've inspired me to do my own posi install (On the Crown Vic) instead of taking it to a friend in the business. I have access to lifts though and that'll make it easier. Great job and thanks for the inspiration!

Here's to mucho placido,

J

[SilverSport]

The .030 pattern does look just right. Let me ask you about your pinion preload. Were you using new crush collars with every shim change and how much preload are you set at? Incorrect preload makes it damn near impossible to have a quiet gearset. I'm sure you have that base covered, but I've seen experienced techs not know how to measure preload with an inch pound torque wrench. It's kinda funny when a parts manager (me) has to come into the shop and teach a tech how to set up gears. HAHA!!

[Stranger in the Black Sedan]

I am using a solid pinion spacer with shims. I hate crush collars and won't use them. Pinion bearing preload is right at 23 in lbs. I bought a nice little made in USA Proto 0-70 in lb dial torque wrench on ebay for only like $60, it was very easy to use measuring rolling preload. Even if you were using a crush collar, you don't have to use any collar at all during test fitting to check the pattern -- just use no collar and set the rolling preload.

I paid a lot of attention to detail because I don't want this thing to be as noisy as it was before.

[Krytin]

Nice work!
Keep us posted during the break-in.

[CRUZTAKER]

Look at my ring and pinion set up pattern -- close?


....and we should care why?:D

[Stranger in the Black Sedan]

This is a tech post, not a look at what I can do post. In fact this is a look at what I can't do post. LOL.

[CRUZTAKER]

This is a tech post, not a look at what I can do post. In fact this is a look at what I can't do post. LOL.

True.

Then all I have to offer is +4. ;)

[Pat]

VEB, My teeth have been on edge since this thread started. I was getting worried, but didn't know how to advise you.

Thank goodness for Jeff. It seems your on the right course now, good luck in finishing the install. I'm confident that it will work.

Good to see that you are willing and able to tackle this large job, keep up your enthusiasm.

Pat

[Stranger in the Black Sedan]

Pat, I build engines and transmissions for fun, so this isn't a daunting task, save for the very fine line between a good and not so good contact pattern. I have the car back on the road, but the gears still whine a little 55+. I found a factory Rotunda tool set I am buying for the 7.5/8.8 rear, so I am going to take it back apart and re check pinion depth. I have only put about 10 miles on the new gears, and I won't drive the car again until I have reset pinion depth, so I don't start generating a wear pattern yet.

If anything, from my most recent picture it looks like maybe I am 1-2 thou too deep at 0.030 pinion shim. The contact pattern looks pretty damn good, although if anything it looks a tiny bit bottom heavy. I want to have the Rotunda tool in hand though before I do another removal/install so I am not just guessing.

Looks like the bottom line is, if you can tolerate slightly noisy gears, you can do a gear install without a proper pinion depth gauge. If you are like me and you really don't want to listen to gears, it looks like a real deal $$$$ pinion depth gage is a must. Funny, Dennis R told me this and of course I thought, I'm smart enough, I'll just look at the pattern. LOL now I am buying the Rotunda gage anyway. Me and my smarts!

[Krytin]

Hey, I would be interested in either renting the pinion depth gauge or even purchasing it from you when you're done!

[GreekGod]

A solid pinion bearing preload spacer is much better/stronger than the crush spacer. It allows changing the pinion yoke and/or the seal without affecting the bearing preload, making either proceedure a simple R&R + torque to spec. (no need to check rotational torque effort).

[MENINBLK]

Knowing your limits is a virtue most DONT possess :D

A-MEN !!! :coolman:

[Stranger in the Black Sedan]

Greekgod, I AM using the solid preload spacer. As far as renting the Rotunda tool from me when I am done, we can work that out, definitely.

Steve

[GreekGod]

Greekgod, I AM using the solid preload spacer.Steve

I was merely elucidating for the benefit of the unwashed masses. Your mention of the solid spacer reminded me it is a commonly overlooked, and useful option.

I believe Ford first started using a solid spacer in performance applications with the 1963 1/2 Galaxie (427-V8) 9" rear axle. They went to 31 spline axle shafts and the "Daytona" pinion support, which used a select fit solid spacer. The Ford Racing solid spacer shim kit works with both the 8.8" and 9".

[Stranger in the Black Sedan]

I just did not like the idea of trying to put 300 ft lbs on a nut, under the car. I don't think I have enough room for a breaker bar that big. I have a 500 ft lb air hammer that would definitely compress the crush sleeve, I used it once before on a 9", but I really don't like hammering against the new bearings for that amount of time. The Ratech solid spacer only needed 125 ft lbs on the pinion nut once proper rolling preload was obtained. Even my skinny arms were able to provide that torque w/ my 1/2" torque wrench.

[GreekGod]

I just did not like the idea of trying to put 300 ft lbs on a nut, under the car. I don't think I have enough room for a breaker bar that big. I have a 500 ft lb air hammer that would definitely compress the crush sleeve, I used it once before on a 9", but I really don't like hammering against the new bearings for that amount of time. The Ratech solid spacer only needed 125 ft lbs on the pinion nut once proper rolling preload was obtained. Even my skinny arms were able to provide that torque w/ my 1/2" torque wrench.

I am sure the pinion nut torque spec. for a solid spacer is about 180 lb. ft. When I changed the yoke on a 9", I called Ford Racing to confirm the number. The reason I remember is because I had to buy another 1/2" torque-wrench, as mine only went to 150 lb. ft.

By the way, Sears has a new 1/2" torque-wrench that is digital/electronic (no turning the handle), and has 3 LED's to let you lnow when approaching peak torque.

[Stranger in the Black Sedan]

Ratech says 125 for the 8.8 solid spacer, I have their instruction sheet.

[Stranger in the Black Sedan]

I won the complete Rotunda pinion depth tool kit on ebay for $255. YEEEEEEHAAA! It's more than $1000 new. They only listed the T79P-4020-A part # in the auction, no application info, so not too many people knew what it was (luckily I searched ebay by part # in descriptions). I can set up an 8.8 like the pro's now. Can't wait to play with it. That just made my day. I was willing to pay quite a bit more for it if I had to, so I was pretty stoked for what I got it for. I should start a loaner tool program with this thing, specifically for members of this board.

[GreekGod]

At $255 you stole it! Let us know how well it works. It should speed up a repair job, but I can't see how it would get a better pattern. I know a Ford service tech that got a noisy gear set from Ford for his personal car, and had to send it back.

[Stranger in the Black Sedan]

At the price I paid it's worth having. I know Dennis Reinhart told me he sets gears by the Rotunda and the set up comes out perfect. The rotunda takes into account bearing tolerances and also housing tolerances. I have a service manual that explains how it works --it's a really slick tool. It goes in place of the pinion, using the pinion bearings. You preload the bearings to spec, and then slide shims in between a carrier gage block and the "dummy pinion" to find the necessary shim.

I'm sure it's not the gear set that's the problem when I eyeballed the pattern and said "looks good to me".

[magindat]

I've seen Dennis's Rotunda in use. Makes child's play of setting up the gears.

[Krytin]

Greekgod, I AM using the solid preload spacer. As far as renting the Rotunda tool from me when I am done, we can work that out, definitely.

Steve
Sorry for being gone for a few days - I still am interested in renting out the tool Steve. Let me know when it's available and I'll get the gears and bearings.
Did you get your install kit from Rattech and if so how did you like it?

Paul

[Stranger in the Black Sedan]

I had a complete install kit included with my genuine Ford OEM 5L3Z-4209-B gear kit.

I only used Ratech for the solid spacer and for carrier shims. Ratech's shims SUCK. All of the carrier and pinion spacer shims had huge, razor sharp burrs around one side of each shim's edges, due to stamping. The huge burrs were effecting the shim stack up height a lot. I had to hand deburr each shim with a file. Ratech feeds you a line of crap about how their shim stock is better than anyone else's blah blah blah, but I have never used shims as bad as theirs. None of the factory Ford shims have burrs on them like their crap.

Ratech has also started making $29 "pinion depth gages", including for the 8.8 (I bought one). It is a very thin flimsy depth gage that has a hole where you insert the end of a caliper (LOL) and try to use the end of your caliper to gage off of the curve carrier bearing journal. It is the biggest joke ever. The aluminum gage flexes so much it is impossible to get a useable reading. Also the hole where you insert the stem end of the caliper is so much larger than the caliper stem that you can basically make the reading anything you want by sliding the caliper around.

Really not impressed with their stuff. Their bearings are Timken supposedly. Ratech's crush collars, by the way, are welded tubing (!!!) instead of the factory seamless tubing used to make the crush collars. AND Ratech's collars are 2/3 the thickness of OE collars. Do not use Ratech's crush collar if you can help it.

Their solid pinion collar was saw-cut and also had a huge burr on the end that had to be filed flat.

Agh! Their stuff looks like I made it.

[Marauderjack]

Uh.....Sounds like you ain't too fond of Ratech....Huh??:confused:

Good Luck with your gears....I've been following this one as I will re-do my rear end soon!!:rolleyes:

Marauderjack:burnout:

[Stranger in the Black Sedan]

I would love to love Ratech but the finish quality of the parts I got look like something that were manufactured out of someone's hobby shop. Having to hand file a whole handful of 10 thou shims was a pain and really should not be necessary. Also like I said, they use welded, not seamless tubing for crush collars, and the wall thickness was way under the stock collar. I calls em like I sees em. Would you rather I lie and say the finish quality of the parts was excellent and they were equivalent to or superior to the factory parts? Just trying to be helpful.

[Krytin]

Thanks Steve! You may have generated one of the more informative threads to date. There has been a lot of good participation all the way around!

[Stranger in the Black Sedan]

I'm glad you think so Krytin. Zack, and it looks like a few others, think I should have never tried to set up gears in the first place. However, I am not afraid to make mistakes, and I recognize this is certainly not a task that is out of anyone's capabilities, given the right tools and enough time. (I mean basically, installing gears is not much more difficult than changing wheel bearings on an old car, but add a small press to get the bearings on/off. The rest is just knowing what to do w/ shims to get the depth right) I'll take some pics of the Rotunda tool in action and let everyone know if that results in my getting the gears spot on.

[Stranger in the Black Sedan]

I have been on vacation (driving someone else's car, LOL). I have Rotunda tool and factory service manual in hand and I tore the car down from running driving car to differential on floor again in a couple hours tonight. I will set the gears per the tool tomorrow and paste them and see what they look like, and install again. The gear noise I had with the 0.030" shim and the pattern I have eyeballed was very, very minor 60-65 but I am pickier than most. Will advise.

[Tom Doan]

When Dennis pulled out a set of used OEM 3:27's I had to have them, but I have been through your nightmares trying to make the rear quiet. Built a whole new Dana 60 for my Roadrunner just to make the rear shut up,it did. Dennis pulled out the Rotunda tool and said I garanteeeee a quiet rear. I have been through bad work that I payied for and said the same thing I have the skills and the tools to do the job. I went to 4:10's back to 3:55's a couple of times because I could, alot of shimming work, but learning what changes what satisfied my questions and curiosity. Time on R&D is never a waste, and I learned alot but.......that tool sure makes it easy. Tom

[Stranger in the Black Sedan]

Yeah, we will find out tomorrow if the Rotunda tool gives me a quiet rear. The rotunda tool assumes perfect published dimensions for the pinion gear, but takes into account deviations in the bearing and housing. If the pinion gear is not nominal thickness the Rotunda will not give perfect depth. However the OEM gears shouldn't deviate more than +/-0.002 max, ever, so the chance of the Rotunda giving the correct depth is probably better than my looking at the pattern and guessing. Aftermarket gears are easier to eyeball the pattern on, it seems, because they give a small oval contact patch, unlike the Ford OEM huge rectangular, diffuse contact patch. The aftermarket gears are made differently.

[TooManyFords]

The rotunda tool assumes perfect published dimensions for the pinion gear, but takes into account deviations in the bearing and housing. If the pinion gear is not nominal thickness the Rotunda will not give perfect depth.

I would have worded it this way:

The housing is machined to exact tolerances and the Rotunta tool places the face of the pinion gear in an exact location regardless of the thickness of the gear. That is why there can be variances in the pinion gear and it always tells you the correct shim to get the perfect pattern.

The last sentence though seems to be incorrect. Regardless of the thickness of the pinion gear, it shows you which shim to use so your pattern is correct. That's the whole point of using the Rotunda too.

As I have stated before (several times) here in the forum, the tool is not needed to achieve a perfect shim size and pattern. I won't hijack this thread any further but if someone wants the 411 on how to do it this way, start another thread and ask.

john

[Stranger in the Black Sedan]

The factory service manual includes instructions on having to possibly check the pattern and adjust the shims from where the rotunda tool put them. The rotunda basically gives you a very accurate starting point, which may in fact be the ending point if the gear is perfect. Since the rotunda uses a "dummy" pinion gear of published dimension, variances in the actual gear may require adjustment up to +/-0.002 from where the tool measured the shim thickness. In order to account for a different thickness of the actual pinion gear, you would have to have a tool that measured the pinion gear in the housing, instead of assuming it is a certain thickness. Some of the older Ford gears would have a number written on them in paint pen ie. +1, -1, +2, -2, corresponding to thousandths, that you would add or subtract from the # the rotunda gave you, based on the variance of the pinion gear from nominal thickness. Thanks. Time to play with the fancy tool.

[TooManyFords]

The factory service manual includes instructions on having to possibly check the pattern and adjust the shims from where the rotunda tool put them. Since the rotunda uses a "dummy" pinion gear of published dimension, variances in the actual gear may require adjustment up to +/-0.002 from where the tool measured the shim thickness. Some of the older Ford gears would have a number written on them in paint pen ie. +1, -1, +2, -2, corresponding to thousandths, that you would add or subtract from the # the rotunda gave you.


See, that is where you have it wrong. The numbers painted or stamped on the head of the pinion gear is the addition or subtraction of the factory sized shim to use and is based on the thickness of the pinion gear itself. Even without the tool, you could take this number and figure the difference of the previous pinion gear thickness and arrive at the correct shim thickness. That is why it is written on it. Not as a reference to the tool, but as a reference to the existing configuration.

John

[Stranger in the Black Sedan]

Alrighty, I used the Rotunda tool w/ a new set of bearings, and came up with 0.024 shim recommended (you can't compare this to the 0.030 shim I was running before though because I was using a used Koyo pinion head bearing. The new Timken pinion head bearing put the pinion head out further towards the ring than the used Koyo did. Either way it looks like the tool wants the pinion shallower than I had it. I took pictures of using the Rotunda tool and will post them later tonight if anyone is interested.

[knine]

Knowing your limits is a virtue most DONT possess :D
This is why I rarely venture out of the house.

At the risk of hearing a loud pop (figure that one out), I gotta give one to the Z-mister here. The guy he set me up with a couple of weeks ago was dead-on with the 4:10 install. Knock-on-woodie, no problems. A true Egg-spurt.

[TooManyFords]

Alrighty, I used the Rotunda tool w/ a new set of bearings, and came up with 0.024 shim recommended (you can't compare this to the 0.030 shim I was running before though because I was using a used Koyo pinion head bearing. The new Timken pinion head bearing put the pinion head out further towards the ring than the used Koyo did. Either way it looks like the tool wants the pinion shallower than I had it. I took pictures of using the Rotunda tool and will post them later tonight if anyone is interested.

Good job on the setup. Yes, please post the pics.

Cheers!

John

[Stranger in the Black Sedan]

At the risk of hearing a loud pop (figure that one out), I gotta give one to the Z-mister here. The guy he set me up with a couple of weeks ago was dead-on with the 4:10 install. Knock-on-woodie, no problems.

OK does anyone else want to post non helpful information? Going once, going twice ...

[knine]

OK does anyone else want to post non helpful information? Going once, going twice ...

Hmmmm, if giving credit to a person and underscoring the purpose of this site (I.E., helping each other out) isn't usefull, then neither is my advise of where you can go.

[Stranger in the Black Sedan]

I'm really not interested in who can set up my gears though, if you have read this post -- it's a DIY gear set up venture. I could have easily had someone else do it, that's not the point. I also now own a Rotunda tool if I ever have to set up gears in any Ford rear again.

If you think telling someone who is asking for help on how to do something themselves, "somebody else can do this job easier and better", is HELPFUL, I don't know what to tell YOU

[Stranger in the Black Sedan]

All set, thanks for the support I did get, and thanks to the other guys who don't set up their own gears but still wanted to poop in my thread. Although with a newer car like this it doesn't surprise me that not everyone does all their own work. The satisfaction is worth it though if you are adventurous enough and have the time.

[1stMerc]

Congrats, and thanks for the info. I take it all is well now.

[Stranger in the Black Sedan]

The Rotunda tool is really the only way to go if you are using Ford gears, I could have saved soooo many trial and error installs. Never again without it.