Finally doing the 4.10 gear swap...

[MrBluGruv]

So I'm finally biting the bullet and gonna have some fun with the car. :)

I just wanted some clarification on a few things, I've been linked that I should get the Ford Ring and Pinion install kit along with the Axle Bearing kit, which is affordable enough, but while looking at the trac-lok rebuild kit I noticed they had two:

M-4700-C:
http://www.summitracing.com/parts/FMS-M-4700-C?autofilter=1&part=FMS-M-4700-C&N=700+4294925134+400070+115&autoview=sku


And M-4700-B:
http://www.summitracing.com/parts/FMS-M-4700-B/


What differences am I looking at here that make the 'B' pack better than the 'C'? I'd like to save the extra money where I can but I don't want to pass up on something I need. Also, if anyone has any thoughts on the other two items I've been referenced (Ring and Pinion install kit and Axle bearing kit), please let me know. At the risk of sounding cheapo here, I'm trying to keep my costs at an absolute minimum while still being practical and avoiding the more probably risks of not walking into this fully prepared. That being said too, does around $500 seem outrageous for a gear install? Keep in mind I'm in south-central Texas, anyone thoughts from someone in the region would be extra helpful.


On a similar note, with the expectation that I may be hitting 120 and above, would you guys figure it'd be more practical to get my stock driveshaft balanced and maybe get the metco driveshaft loop or just go for the aftermarket driveshaft from say Reinhart?

Thanks.

[Bradley G]

The "C" kit has a heavier S spring and the clutch material is beefier than what comes stock.
My installer said it is a real tight fit.
No extra clutch(common upgrade) was able to fit, with the thicker spring.

[LANDY]

On a similar note, with the expectation that I may be hitting 120 and above, would you guys figure it'd be more practical to get my stock driveshaft balanced and maybe get the metco driveshaft loop or just go for the aftermarket driveshaft from say Reinhart?)

Thanks.
dynotech driveshaft.
i have it, and a couple of days ago early in the moning i did 140mph shown on my gps no vibration and still pulling.:beer:

[MrBluGruv]

The "C" kit has a heavier S spring and the clutch material is beefier than what comes stock.
My installer said it is a real tight fit.
No extra clutch(common upgrade) was able to fit, with the thicker spring.

So then realistically the 'B' kit is closer to a stock replacement? I don't think I need that extra umph as I don't really ever plan on going FI for this car and I rarely spin/burn the tires anyway. Going on 86k miles and still got positive lock on my setup now. So long as the B kit has everything I need(?) that may be the way I go then.

Also, the safety minded side of me says i should go for the dynotech, but if I rarely even get the car up to 120 and only occasionally a very little above it (140+ will NEVER happen again), I'm just curious if I would be WAY better off getting my stock driveshaft balanced and get the metco loop.

[Glenn]

If your going to install the 4:10 gears it makes no sense not to use the "C" HD Cobra kit. You can install an extra shim with the HD F150 "S" spring it just takes alot of work with the car on a lift and a big hammer. Have an experienced Mustang shop install it for you. If they say they can not install the HD kit go to someone else - you got the wrong shop. Ask me how I know - 3 blown rears and my HD Cobra kit is doing great. The "C" kit also include the much better carbon fiber clutch discs.

Also, shop prices at your Ford FRPP parts counter. You should be able to get 30% off list just by talking English to the Parts Manager.

Glenn :burnout:

[MrBluGruv]

Sounds good. All that being said though, I'll still have anything and everything I could need with the gears, install kit and axle bearing kit along with the trak-lok rebuild kit 'C' yes?

[Glenn]

The friction modifier is criticial to the successfull installation of the carbon fiber discs or even standard discs. They must be soaked in the modifier for several hours to do it right. If not you will have problems.

Glenn :burnout:

[MrBluGruv]

K so then Kit 'C', ring and pinion install kit, axle bearing kit, friction modifier extra, and of course the actual set of gears and I'm golden then.

Does the $500 tag seem about right for a speed shop or a garage to do the install work?

[Blackened300a]

K so then Kit 'C', ring and pinion install kit, axle bearing kit, friction modifier extra, and of course the actual set of gears and I'm golden then.

Does the $500 tag seem about right for a speed shop or a garage to do the install work?

That seems a little pricey but its been a while since I went install shopping. Make sure you adjust your tune for the 4.10s or if you dont have one, you'll need one to calibrate the speedo and the trans schedule.
I used royal purple gear oil which includes friction modifier in it.

[2,4shofast]

$500 is higher than normal but it just all depends on your location when it comes to stuff like this. Normally from around $200 to $450 seems to be common price. But if it is a good trustworthy mechanic I would pay a little extra for the peace of mind and knowing it will not have to be done again anytime in the near future.

[Glenn]

Make sure you test drive the MM after the install WITH the mechanic in the car and drive it at highway speeds before paying. If it is nosiy - have them fix it. The install should be completely noiseless. If not they did something wrong. $500 is alot - $400 is about average, but many are done for less.

Glenn :burnout:

[ctrlraven]

$500 is about right if the shop is rebuilding the diff along with everything else. I was quoted $500-600 for diff rebuild, new axle bearings installed and 4.10 gears installed.

A friend of mine is installing new diff, 4.10 gears and axle bearings for $150. Also picked me up a 04 CV Ford shop repair manual woohoo.

[MrBluGruv]

The guy that will be doing the install worked for Ford for a number of years with countless gear swaps, so if $500 seems ballpark for a guaranteed good install then sounds like I'm set. :)




I used royal purple gear oil which includes friction modifier in it.

So basically you were able to avoid the extra friction modifier with the royal purple altogether?


I really appreciate all the help guys, I know I'm surely asking a lot of stupid questions but you guys have been invaluable for me. :up:

[Glenn]

Your call, but I would stick with the Ford FM.

Glenn :burnout:

[MrBluGruv]

K guys, sorry to dig up an old thread, but I feel it more appropriate than wasting the space of starting a new one with the same subject.

I got my car back today from the shop installing my 4.10 setup. I've replaced every concievable thing but the housing and the cage for the gears, as the axles were spent pretty good due to the bearings sucking.

My question is this, as the shop owner recommended something WILDLY different than what I've heard here and elsewhere: I understand I should allow for about 500 miles of break-in with the new gears, taking it easy and varying speed over long periods of time etc, but whenabouts should I take the car in to have the diff drained, checked, and refilled? And should I do it more than once?

[ImpalaSlayer]

i let mine break in for about, oh 300 feet before i started thrashing them. no problems 15k later. i really dont understand the break in thing for gears, did people here wait 500 miles to beat on there brand new mm? i think not.

[LeoVampire]

K guys, sorry to dig up an old thread, but I feel it more appropriate than wasting the space of starting a new one with the same subject.

I got my car back today from the shop installing my 4.10 setup. I've replaced every concievable thing but the housing and the cage for the gears, as the axles were spent pretty good due to the bearings sucking.

My question is this, as the shop owner recommended something WILDLY different than what I've heard here and elsewhere: I understand I should allow for about 500 miles of break-in with the new gears, taking it easy and varying speed over long periods of time etc, but whenabouts should I take the car in to have the diff drained, checked, and refilled? And should I do it more than once?


So doing a change out is never a bad idea and it give's you a chance to see if there are any defective parts installed that might create a problem down the road.

As to the break in it is subjective and usualy a good idea incase something is defective from the manufacture.

[MrBluGruv]

I'm just wanting to be extra sure, I'm not really in a position to afford too many more immediate problems with the car right now. :(

Lemme ask you this at least though, regardless of the immediate thrashing: did you go back later to have the fluid checked and replaced?

[ImpalaSlayer]

I'm just wanting to be extra sure, I'm not really in a position to afford too many more immediate problems with the car right now. :(

Lemme ask you this at least though, regardless of the immediate thrashing: did you go back later to have the fluid checked and replaced?

well i went about maybe 50 miles and my axle seal started leaking, the guy that did it must have nicked it with the axle when he put it back in. then about oh i duno lets say 8 months later i broke a lug nut (long story) and had to remove the axle again therefore the fluid was changed again. i know this doesn't help much but that is what happened with my gear install

[Black_Out]

You want the C kit, carbon fiber clutches and a more aggressive spring. You'll be pissed if you don't.

[MrBluGruv]

lol, everything has been done already, the initial question about what should I buy is irrelavent now. Thanks for the responses about the break-in period though guys. :)

[Got_1]

well.....how do you like it?

[MrBluGruv]

oh man, lemme tell ya, the difference is phenomenal. There is no doubt in my mind the truth when guys say the car should've come like this from the factory. The increased ability to get going from a stop alone makes this car feel more right. First gear actually scared me a bit in the higher rpms, the tug was much more than I'm used to with the 3.55 and it was enough to truly put me back in the seat. Getting to 60 is effortless. I really, REALLY am glad I did this, despite the huge price tag it ended up having in my case. Only thing I can't vouch for yet is the gas mileage impact.

[RF Overlord]

BluGruv, if the the axles were bad (I think you said that), then you could have some wear metals floating around in there. I just did the rear axles on Phoebe and I found some glittery material in the bottom of the diff housing. I used cheap-o 75W-90 gear lube this time as I'm gonna drain it again in 100 miles or so, then refill with Motorcraft synthetic 75W-140.

[MrBluGruv]

I'm pretty sure my mechanic checked on that when he pulled what ended up being pretty much EVERYTHING out of there. :( But, I am planning on having the fluid checked and things changed and serviced as necessary, at this point at probably around 500 miles in.