Blowed-up Pumpkin

[mrogerc]

Today my differential bit the big one. I was concerned at first that it might be the tranny, but confirmed that the drive shaft moves but the wheels just shudder.

Makes a really bad noise and ain't goin' anywhere until it is fixed.

So, I am planning to replace it with an Eaton differential, perhaps with 410 gears. Some questions:

What is a good source for fast delivery for the differential?

Anyone know the part numbers?

What is the best way to find a good rear end shop?

What else should I have done "while I am at it?"

Thanks.

[FordNut]

A few suggestions to make it more durable...

Weld the axle tubes to the center section.
Go to 31 spline axles (Dennis can fix you up with these)
Get the 31 spline differential unit.
Put in the stud kit and girdle.

[Mike Poore]

...
Put in the stud kit and girdle.
http://www.mercurymarauder.net/gallery/data/500/thumbs/shineyhiney4.jpg (http://www.mercurymarauder.net/gallery/uploads/2548/shineyhiney4.jpg) Join the club
That's a Shiney Hiney, you can get it from Wes Chain at Innovative Interceptors, one of our contributing sponsors.

I see the tri-bander DE W3CAR. ;)

[Tallboy]

If it was me [and I'm sure one day it will be] I'd be on the phone to Summit racing. They stock the Eaton unit. Fast, efficient service.

[mrogerc]

I see the tri-bander DE W3CAR. ;)

Thanks and 73 DE NM0EJ.

[mrogerc]

And another question: How much fuel economy do you give up going from 355's to 410's?

[rayjay]

And another question: How much fuel economy do you give up going from 355's to 410's?
Seems like its in the 2-2.5 MPG range from what I've read here. I also have an 04 DTR, N/A with some mods. Do you know what caused the failure?

[RoyLPita]

Today my differential bit the big one. I was concerned at first that it might be the tranny, but confirmed that the drive shaft moves but the wheels just shudder.
Makes a really bad noise and ain't goin' anywhere until it is fixed.
So, I am planning to replace it with an Eaton differential, perhaps with 410 gears. Some questions:
What is a good source for fast delivery for the differential?
Anyone know the part numbers?
What is the best way to find a good rear end shop?
What else should I have done "while I am at it?"
Thanks.

As for what else to replace. Have everthing inspected when the shop takes it apart. They will tell you what else you will need. If not, replace all bearings, cups, and seals. Make ure that they get rid of any debris.

Make sure that they don't leave any shop rags in the pumpkin area. <--True story.

[mrogerc]

Do you know what caused the failure?

In all likelyhood, a great deal of really fun abuse. :beer:

Actually, this spring I put the Nittos 305s on. When I first put them on, they would still spin on hard acceleration, but not nearly as much as my factory tires.

Lately, I have noticed a change. The tires would hardly chirp, and simultaneously, my MPG seemed down as well. I now suspect that these were signs of the differential getting sick. I wonder if the fact that the Nittos hook up so much better than the factory tires added a great deal of additional stress to the differential.

I have also heard that if you do a fair number of burnouts, you should have the differential fluid changed much more regularly. Of course, I ignored this advice. :shake:

[BillyGman]

Here's a link to the Summit racing page where you'll find the Eaton posi unit:



http://store.summitracing.com/

if you're going with a 31 spline axle, then the Eaton posi unit part # will be ETN-19588-010

...and if you're going to stay with the stock 28 spline axles, then the part # is ETN-19605-010

When I went from the 3.55's to the 4.10's, it reduced my gas mileage by 2 MPG. Did you say the rear end housing itself was destroyed? I've never heard of that happening on a 8.8 rear end. What was the cause? Did you recently have gears installed? If so, were they making noise?

EDIT: except in the case of running slicks on the dragstrip. If you were doing that, then that would also explain it. They grab the asphalt so abrubtly during the launch that all the shock goes to the drivetrain. I've heard stories amongst guys who use slicks with cars that launch hard, of ring & pinion gear teeth being ripped apart, as well as U-joints being snapped.

[Glenn]

NM0EJ:

Good luck on your rebuild. The rear girdle is a must. It may have prevented the problem.

73's

K3ZOT

[GarageMahal]

Sorry to hear about your car. I had Midway Ford install my 4:10s. They work on a lot of CVPIs and have always done a good job for me. Not the cheapest place however.

Hopefully I can meet you and your car someday. I would really like to see and hear your stereo upgrades.

jta

[mrogerc]

Did you say the rear end housing itself was destroyed? I've never heard of that happening on a 8.8 rear end. What was the cause? Did you recently have gears installed? If so, were they making noise?



No noise or other warning, and no, the housing itself still looks OK. In fact, there were no leaks.

However, when I tried to move the car, it made a helluva sick grinding noise. And when I pushed the parking brake all the way in, put it in drive, and looked underneath, the driveshaft was spinning along nicely, while the rear axle and wheels just shuddered........

I really wonder if the Nittos have too much grip for the stock differential with 355 gears and the Trilogy kit.

Thanks, Billy.

[mrogerc]

Sorry to hear about your car. I had Midway Ford install my 4:10s. They work on a lot of CVPIs and have always done a good job for me. Not the cheapest place however.

Hopefully I can meet you and your car someday. I would really like to see and hear your stereo upgrades.

jta

Thanks, and BTW, I will be in town the weekend of July 23-24, spending most of Sunday cleaning the garage.......

[BillyGman]

No noise or other warning, and no, the housing itself still looks OK. In fact, there were no leaks.

However, when I tried to move the car, it made a helluva sick grinding noise. And when I pushed the parking brake all the way in, put it in drive, and looked underneath, the driveshaft was spinning along nicely, while the rear axle and wheels just shuddered........

I really wonder if the Nittos have too much grip for the stock differential with 355 gears and the Trilogy kit.

Thanks, Billy.And thankyou for clarifying that for us. Sounds like you either ripped up the splines on the axles, or you ripped a bunch of teeth off of the ring & pinion gears. One of the possible causes of ring & pinion gear teeth failure is the ring gear bolts being worked loose and falling in between the ring & pinion (ouch!!). That can happen especially when permanant LOC-TITE isn't used on the ring gear bolt threads (which is precisely why I used LOC-TITE thread Locker on the ring gear bolts of my Marauder when I installed the gears). As far as the Nitto's being a cause of the failure, I dunno. I wouldn't be too quick to conclude that, because there are many of us who have the same supercharger as you do, and who also have the Nitto drag radials, and that hasn't happened to our cars.And I don't run a rear end girdle on my car either, and the rear is just fine after 31,000 miles (20,000 supercharged miles).

I don't know how often you take your car to the track. I only take my car there once or twice per year. I've only put 20 quartermile passes on my car, 12 of them when it was N/A, and 8 of them since it's been supercharged. I suppose it's possible for drag radials to be a contributing factor to reduced axle or ring & pinion gear life if the car is raced often at the track, since those tires will grab on the track a lot better than on the street due to all the VHT traction compound they use at the dragstrip. On my car, I still usually get a momentary half or a quarter turn of tire spin at the track during the launch for a split second before the Nitto tires grab completely. So while I'm sure that the use of drag radials on the dragstrip sends more of a shock through the drivetrain during the launch than using standard radials would (which would be spinning all over the place), I don't think it's as rough on the drivetrain as slicks are since you don't even get that quarter or half turn of wheelspin with slicks like you often will with drag radials coming off the line. But please let us know what they find when they open up that rear end on your car.

Another thing that comes to mind, for what it's worth, is if you do burnouts around turns, or an ocassional doughnut burnout, then it's my understanding that those can also be pretty tough on rear ends. A lot tougher than straight line burnouts are. That's why I don't do doughnuts with my car. Good luck with your rebuild.

[AzMarauder]

What else should I have done "while I am at it?"

Thanks.
I would echo all that has been said so far. However, until you pull it down you won't know for sure what is wrong. Of course if you are going to be changing axles, carrier, etc. heck you'll be changing everything that COULD be wrong !

:D

[BillyGman]

Just a little tip for ya here in light of what I've stated in my last post in this thread......

I strongly suggest that anyone who has rear end work done to their car which includes a ring & pinion gear change, purchase a bottle of the RED LOC-TITE thread locker (sometimes listed as LOC-TITE#271) and bring it to the dealer or garage that the work will be performed at, and hand it to the service writer or mechanic, and request that it be used on the ring gear bolt threads. Because a number of mechanics will NOT use thread locker on the ring gear bolts unless you request that they do (and hopefully they will IF you hand them a bottle of it and make your request known to them). It only costs $5 or $10 at your local auto parts store or machinist tool supply place, and it's well worth it.

[mrogerc]

Found a shop today that does a lot of work on short track an drag race cars--and within OK towing distance of my car's current position.

Nice folks, when I told them the price I found on the Eaton differential on the Internet, they suggested I just buy the parts and drop ship to save me some $$$.

From the symptoms, they suggested I go ahead and buy new pinion and ring gears as well as the differential and install kit.

I hope to have my car back by the end of the week, and the broken parts, which I will promptly photograph and post here for all to see and comment on.

Thanks for being a great community,

Mike

[AzMarauder]

Found a shop today that does a lot of work on short track an drag race cars--and within OK towing distance of my car's current position.

Nice folks, when I told them the price I found on the Eaton differential on the Internet, they suggested I just buy the parts and drop ship to save me some $$$.

From the symptoms, they suggested I go ahead and buy new pinion and ring gears as well as the differential and install kit.

I hope to have my car back by the end of the week, and the broken parts, which I will promptly photograph and post here for all to see and comment on.

Thanks for being a great community,

Mike
OBTW... it is much more MANLY to shell the rear end at the starting line of the drag strip. That way you can climb out of the car while everyone in crowd ooohs and aaaaahhs.

As me how I know this ! :eek:

(2 x 8" slicks for $100 + 37 year old 28 spline axles = stationary Fairlane with a $1300 problem)

[BillyGman]

OBTW... it is much more MANLY to shell the rear end at the starting line of the drag strip. LOL!!!! :baaa: :baaa: :baaa:

Do you have any pics of your 67 Fairlane that you can post? Those cars are so cool looking (especially from the front view).

[AzMarauder]

LOL!!!! :baaa: :baaa: :baaa:

Do you have any pics of your 67 Fairlane that you can post? Those cars are so cool looking (especially from the front view).My Fairlane looks terrible (goes for paint sometime next month) but has come a LONG way from when I got it 4 years ago. Right now it has run a best of 13.20 at 104. The dual quads are not tuned correctly however. Fighting to get them sorted out at this elevation (5k Foot). The car is a 12 second ride when I get that sorted out and track temperature lower than 120 degrees ! :rolleyes:

[BillyGman]

Thanks for the pics. Sounds like a labor of love alright. I know how that is. But having a big block under the hood is all worth it. My favorite year of that car was the 63's. I especially like the grill on those cars.

[mrogerc]

Today I got two calls from the shop that is working on my car. The first was to give me good news: The part that broke was an Axle, and they thought the differential was probably fine. To be sure, however, they were taking the carrier out to check the condition of everything.

Then I got the second call----looks like I need the new differential after all, but at least I get my car back on Friday.

The shop is convinced that the primary failure was the axle, and that the differential was secondary.

In any case, I am glad to be putting the Eaton unit in and hopefully this will take care of me for a while......

[BillyGman]

Sounds to me like the Eaton is a good choice. Thanks for the update. What gear ratio have you chosen?

[AzMarauder]

Today I got two calls from the shop that is working on my car. The first was to give me good news: The part that broke was an Axle, and they thought the differential was probably fine. To be sure, however, they were taking the carrier out to check the condition of everything.

Then I got the second call----looks like I need the new differential after all, but at least I get my car back on Friday.

The shop is convinced that the primary failure was the axle, and that the differential was secondary.

In any case, I am glad to be putting the Eaton unit in and hopefully this will take care of me for a while......
That was the case with my Fairlane... axle snapped about 3" down from the splined end, jammed the carrier, cracked it, cracked the maincaps in the third member. Only thing that survived were the gears and the axle housing.

[mrogerc]

Sounds to me like the Eaton is a good choice. Thanks for the update. What gear ratio have you chosen?

Given that I drive it to work every day, want to keep the RPMs down to keep noise under control, and am cheap, I stayed with the 355s.

Since the car already accelerates better than anything I have experienced before, I think I can live with the stock gears.....

[BillyGman]

Since the car already accelerates better than anything I have experienced before, I think I can live with the stock gears.....Nothing wrong with that.

[mrogerc]

Nothing wrong with that.

True, but I won't be doing any low 12's times either.....of course, I would have to actually get to a track, anyway.

[mrogerc]

That was the case with my Fairlane... axle snapped about 3" down from the splined end, jammed the carrier, cracked it, cracked the maincaps in the third member. Only thing that survived were the gears and the axle housing.

Sure sounds similar. Aparently my axle snapped near the spline, and the rest happened fast.

I will get the old parts on Friday, and hopefully will have pictures posted by Monday.

[Bluerauder]

I thought we were talking about these ...... :rolleyes:

[AzMarauder]

No.. those are THROWED-UP Pumpkins.... Not "Blowed-up" Pumpkins. :coolman:

[mrogerc]

I thought we were talking about these ...... :rolleyes:

Those are nice, but I always wanted to create something called "exit wound" pumpkin.

[BillyGman]

Those are nice, but I always wanted to create something called "exit wound" pumpkin.LOL....how about "exit wound" manhole cover??? :D

[mrogerc]

LOL....how about "exit wound" manhole cover??? :D

What were those shot with?

[mrogerc]

So I visited my car in the shop today. The break in the axle is one ugly looking thing, and the splines in the carrier look pretty bad too.

I will have some very heavy and expensive souvenirs to show when I get a chance to take some pictures.

Can't wait to be back on the road.

[BillyGman]

What were those shot with?My bolt action single-shot Barrett 50 BMG caliber rifle. The first three shots were with armor piercing rounds, but then after the fourth and fifth shots with standard non-armor piercing rounds went through the manhole cover also w/out any problem, then my shooting partner and I just put the armor piercing rounds away, and continued to punch holes in it with the standard 50 BMG ammo. It was lots of fun. That thing easily weighed 150 LBS, and varied from 1.125" thickness (on the flat parts), to 1.550" thick (near the webbed parts). Yes, I measured it.....:D

[JohnE]

Ford makes 31 spline axles for the Panther. They come on the Limo package.

If you buy new ring gear bolts, they have thread sealer already on them. These are grade 8 bolt IIRC, so reuse with red locktite would be my advice.

[BillyGman]

Ford makes 31 spline axles for the Panther. They come on the Limo package.

If you buy new ring gear bolts, they have thread sealer already on them. These are grade 8 bolt IIRC, so reuse with red locktite would be my advice.Not all ring gear bolts come with the dry film LOC-tite on them. Only some do. The ones that don't should have the liquid LOC-tite used on them.

[GreekGod]

Good to know about Ford/Panther/8.8-31spl. I thought I read somewhere that the 1st year Panther (79?) came with 9" rears. I finally saw one 2-3 months ago and it definitely had OEM 8.8". Since most "experts" agree OEM 28 spl axles are only good for about 350 hp:down: , I'm surprised there aren't more posts of failed axles, especially with all the high output engines in MM's on this site. Years ago I snapped in two :cry: a 28 spl axle in my 68 F100 2wd (100 hp?) with the tired old hi mile 240-6 cylinder! I would think a 9" with aftermarket 31's and a Detroit locker is the best setup for our MM's. Besides the "convenience" of a removable center section it has the addition of semi-floating axles that ride on real bearings and races instead of crappy Chevrolet style "needle" bearings riding on the polished axle shaft and retained by c-clips! I don't have a current NHRA rule book but I believe a fast (12.0) or quicker car besides needing a "cage" or roll bar of some kind would also need a bearing retainer kit of some kind for when an axle breaks.:banana2:
Ford makes 31 spline axles for the Panther. They come on the Limo package.

If you buy new ring gear bolts, they have thread sealer already on them. These are grade 8 bolt IIRC, so reuse with red locktite would be my advice.

[mrogerc]

I got my car back today, and it is running fine.

I did stay with 28 spline axles, mostly because of the typical issues with timing of parts for a daily driver. I am strongly considering getting a little truck for utility and back-up purposes.

However, I understand that there is also an option for higher strength 28s, and this winter I just may get some.

The shop that did my work is a tranny/rear end shop that a local speed shop reccomended. Turns out that they do a great deal of drag racing/dirt track work. Some comments and opinions from them:

"We thought for sure that the problem was a faulty axle until the car was put together and we drove it. Now we think it may be just plain too much power!"

"Unbelievable how fast your car is."

"One of our drag racing customers came in today and told us that those tires (Nitto 305 Extreme Drag) are actually softer than slicks. He suggested you might want to change to something with a little less stick to avoid this happening again."

My favorite:

"I gotta get me one of those."

By the way, does anyone know if Lidio switched to 31 spline axles???? I need to give him a call.

Pictures of the carnage early next week.........

[BigMerc]

For safety sake I went to a set of 31 spline axles by Moser also a detroit locker, just helps the mind to know its pretty stout back there.

[BillyGman]

Lidio told me that since we have automatic transmissions in our cars, we can get away with 28 spline axles until we begin getting into the low 11 second bracket. Because automatic transmissions are softer on the rear end and axles than manual transmissions are due to the torque converter. I'm not saying that it's neccessarily wrong to switch to a 31 spline set-up, but just that it isn't mandatory just because you've supercharged your Marauder.

Those are some pretty nice compliments that you received about your Marauder. I know how that feels when people react to your car like that. As far as the Nitto tires being as soft as slicks, I dunno about that, but even if they are, they're still not going to grab as sudden as slicks will since they don't have a side wall that wrinkles up like slicks do, because they're radial tires, that are designed to take some corners on the street too (unlike slicks).

[GreekGod]

Did you get a safety/retainer kit with Moser axles? I thought they were required with a Detroit locker. The axle upgrade alone is an excellent safety choice for a small price (about $300+ or so). Do you have a girdle too?
For safety sake I went to a set of 31 spline axles by Moser also a detroit locker, just helps the mind to know its pretty stout back there.

[BillyGman]

For safety sake I went to a set of 31 spline axles by Moser also a detroit locker, just helps the mind to know its pretty stout back there.Then you must reserve your car for driving on the dragstrip, because locker rear ends are very noisy around turns, and will often have your passengers asking you what's wrong with your car while you're going around turns. The only lockers that I've ever heard of that are supposed to be quiet around turns (ie w/out that loud clicking noise) are the "No-Slip" Powertrax units offered by Richmond gear.

[GreekGod]

My '79 F150 4x4 has had 4.11 (rear) Detroit locker for years now. It is somewhat noisy at times but the more disconcerting aspect of it's operation is the catching when it engages. It kind of sounds like the noise you hear when you break the teeth off differential side gears. I've just learned to expect the noise and abrupt engagement and live with it. My '68 F100 4x2 also had a (3.50) Detroit locker that wasn't nearly as noticeable. Never knew why but the '79 surprised me because it was so much more noticeable than the '68. Perhaps the 428 in the '79 "works" the rear end harder than 240 in the '68 did.
Then you must reserve your car for driving on the dragstrip, because locker rear ends are very noisy around turns, and will often have your passengers asking you what's wrong with your car while you're going around turns. The only lockers that I've ever heard of that are supposed to be quiet around turns (ie w/out that loud clicking noise) are the "No-Slip" Powertrax units offered by Richmond gear.

[mrogerc]

OK, here are the pictures:

The broken Axle:

http://www.mercurymarauder.net/gallery/showphoto.php?photo=7071&cat=502&page=1

A close-up view:

http://www.mercurymarauder.net/gallery/showphoto.php?photo=7073&cat=502&page=1

The returned carrier assembly:

http://www.mercurymarauder.net/gallery/showphoto.php?photo=7074&cat=502&page=1

The good end of the carrier:

http://www.mercurymarauder.net/gallery/showphoto.php?photo=7075&cat=502&page=1

Then end my axle killed:

http://www.mercurymarauder.net/gallery/showphoto.php?photo=7076&cat=502&page=1

There you go!

[BillyGman]

Those pics are NOT pretty at all!!! Thanks for posting them though.