8.8 TrueTrac Problems?
- Thread starter ricardoa1
- Start date
i have been daily driving a tru trac for a couple of years now, and i haven't run into any of the problems described in this thread. when i first installed it i do recall hearing some light popping, but it seemed to go away within a couple of weeks. overall i am very pleased with it and plan on putting another one in my second terminator
I had a local buddy build it that works at a shop, he has built several for me and others. Second time it was built by a specialty Ford shop 35 miles away. The all new second unit, was built by a rearend specialist in California. Yes, I shipped him all the parts and he built it and shipped it back. I was willing to spend the extra in freight charges just to be sure it was right this time. When I got that unit back I installed it and shipped him the unit from the car. He went through it and shipped it back.
If your lost.... I don't blame you.
First rearend:
built local with all new parts (truetrac, Motive gears and all bearings).
Took to Ford specialty shop, they installed new bearing, removed Motive gear and installed GT500 gears.
Second rearend:
Bought another 8.8 housing, truetrac and GT500 gears
shipped all to California, got it back and installed it
Shipped first 8.8 to California and he went through it reusing truetrac and GT500 gears, put in all new bearings.
All have made the same rumbling / crunching / popping noise. (with the exception of the first 8.8 after returning from California, I have yet to reinstall it and try it.
One thing I forgot to mention.... The very first build, we could not get the spacer back in between the axles. I called Detroit TT and was told "do not use the spacer with an IRS car", so we left it out. latter I found out that they make a thinner spacer and they shipped me one, it still did not fit. I called them and their suggestion was "grind it down". I used several different size sockets to find one that fit tightly between the axle tips (ended of being a 12mm) so I used a micrometer to measure the socket and ground the spacer down to that same size and installed it. But it has made no difference in the nosie / sound
If your lost.... I don't blame you.
First rearend:
built local with all new parts (truetrac, Motive gears and all bearings).
Took to Ford specialty shop, they installed new bearing, removed Motive gear and installed GT500 gears.
Second rearend:
Bought another 8.8 housing, truetrac and GT500 gears
shipped all to California, got it back and installed it
Shipped first 8.8 to California and he went through it reusing truetrac and GT500 gears, put in all new bearings.
All have made the same rumbling / crunching / popping noise. (with the exception of the first 8.8 after returning from California, I have yet to reinstall it and try it.
One thing I forgot to mention.... The very first build, we could not get the spacer back in between the axles. I called Detroit TT and was told "do not use the spacer with an IRS car", so we left it out. latter I found out that they make a thinner spacer and they shipped me one, it still did not fit. I called them and their suggestion was "grind it down". I used several different size sockets to find one that fit tightly between the axle tips (ended of being a 12mm) so I used a micrometer to measure the socket and ground the spacer down to that same size and installed it. But it has made no difference in the nosie / sound
This sounds like a completely different issue from the "normal" clunks everyone else is hearing. It sounds like either the diff is trashed or the gears weren't set up correctly. One other thing to check is your tire pressures and diameters. If your rear tire diameters are different enough, the differential could be active all the time.
^^^ two different 8.8 housings, built multiple times by different people using all new parts.
Rear tires are identical etc.
Rear tires are identical etc.
I am currently researching "other" brands of posi units. Currently leaning towards buying a Torsen T2 and having it installed in the current spare unit and swapping it with the 8.8 currently in the car. Something has got to make this better. I bet I haven't driven the car 300 miles in 11 months, just because I was worried that something was seriously wrong.
sounds like you're having bad luck. Just saying because everyone else here is having the clunky noises. You're the only one that is getting a grinding noise.
Hmmmm. So pull the detroit tt and go Torsten t2 ??
Ordered new posi
That is one huge problem right there. It says in 50 places not to run Synthetic. Every person I have talked to that has run Synthetic says theirs is loud and pops. Eaton says do not use Synthetic it will cause it to not function correctly and cause to make noise. Run something like Lucus dino oil.
First unit we used Torco fluid. Second unit we used Redline. Same noise both units.
Mine had nonsynthetic in originally and had the clunking issue. I read some people had success with the redline shockproof fluid, so i switched. The clunking is still there but it's not as pronounced. Diff fluid will not make a difference with the amount of slack in the differential. It's just the internal tolerances of the diff.
Reviving an old thread - just because I want to warn prospective buyers
I bought an Eaton TruTrac to go in a 2003 Mach 1 with 60K miles on it. Old Trac-loc was worn out. I had read that the Trutrac was supposed to be smooth and quiet - NOT TRUE.
I'm sure they work great for off-road and drag racing, where you dont care about noise, but on the street it is noisy!
Whenever I put it in neutral and let it freewheel, like when approaching a stop, my car sounds like a tank coming down the road. It has a clunking noise coming out of the rear, an dit does not stop until under 5mph. It is not the bearings - I know what bad bearings sound like, and it was opened up and checked twice more for loose parts or bad bearing. This noise goes away when you get above 40mph. It also clunks a lot and I can hear it crunching and engaging in turns. At first in a sharp turn, it always spins the inside wheel until it locks up, which I hate.
I tried synth and conventional oils - it was actually quieter with the synthetic, but not by much.
I finally went to an Eaton Limited Slip differential with the 400lb springs (much stronger and better holding than the stock Ford diff). It is dead quiet and handles better than it ever did with the stock Ford Trac-lok. This is a conventional limited slip with better design than stock.
My car no longer sounds like it is powered by marbles!
I bought an Eaton TruTrac to go in a 2003 Mach 1 with 60K miles on it. Old Trac-loc was worn out. I had read that the Trutrac was supposed to be smooth and quiet - NOT TRUE.
I'm sure they work great for off-road and drag racing, where you dont care about noise, but on the street it is noisy!
Whenever I put it in neutral and let it freewheel, like when approaching a stop, my car sounds like a tank coming down the road. It has a clunking noise coming out of the rear, an dit does not stop until under 5mph. It is not the bearings - I know what bad bearings sound like, and it was opened up and checked twice more for loose parts or bad bearing. This noise goes away when you get above 40mph. It also clunks a lot and I can hear it crunching and engaging in turns. At first in a sharp turn, it always spins the inside wheel until it locks up, which I hate.
I tried synth and conventional oils - it was actually quieter with the synthetic, but not by much.
I finally went to an Eaton Limited Slip differential with the 400lb springs (much stronger and better holding than the stock Ford diff). It is dead quiet and handles better than it ever did with the stock Ford Trac-lok. This is a conventional limited slip with better design than stock.
My car no longer sounds like it is powered by marbles!
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Do you have anymore info on the one you installed such as a part number??
The Eaton part # for the Limited Slip that I ended up keeping is 19605-010.
This is for 28 spline axles, 8.8" differential.
http://www.jegs.com/i/Eaton/362/19605-010/10002/-1?parentProductId=750876
This is for 28 spline axles, 8.8" differential.
http://www.jegs.com/i/Eaton/362/19605-010/10002/-1?parentProductId=750876
I just put in a 8.8 31-spline TrueTrac a couple months ago and it's dead-quiet. If I didn't know I swear it was just a stock diff. I'm even running AMSOIL synthetic.
I wonder why some people have issues and some don't.....
Riley
I wonder why some people have issues and some don't.....
Riley
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No experience with a TrueTrac. I run a Torsen from Maximum Motorsports. No popping or other noises. DD and never sees a drag strip. Do have a bit of gear noise around 45 and light throttle but I'm sure that it isn't related to the Torsen.
I put a truetrac in a few months ago, and it seems that I got one of the noisy units as well. I was hoping to find some simple fix, like a different type of fluid or something. The worst noise occurs when I am just coasting in a straight line. There is a lot of grinding and moaning. It sounds like I'm driving an old, beat up dump truck. I hate driving the car now.
weird that you get griding and moaning. mine is only noisy during load/no load transition. The symptoms i get are as if the backlash was not set correctly. However, I opened the diff and verified it is well within spec. It's the internal tolerances of the trutrac that's causing my clunking. I'm very disappointed with it. I've written to the manufacturer who seems to tell everyone this is normal even though some people have no noise at all.
Yeah, when I let off the throttle and coast, I get the grinding or buzzing noise. But even besides that, it intermittently makes all types of weird noises -sometimes a clacking or ratcheting sound, sometimes a high pitched noise -like birds chirping. But on the dragstrip, I am impressed with it so far. Car launches much more straight and is much more controllable.
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