Truetrac Failure

[wicked stang]

Installed the truetrac that I bought new from a member on this forum along with new gears and all new bearings and races a couple months ago. Took the cover off today to change the fluid and make sure there were no metal shavings. Instead of any shavings I found big chunks of metal...

The edge of the truetrac housing/body on the passenger side had big chunks missing that were laying at the bottom of the axle housing. All of the side cover bolts into the truetrac were loose enough that I could turn them by hand. So it seems like the bolts loosened up enough for the side cover to shift around and bust the edges of the housing off. Was doing a bit of searching and it seems like the bolts coming loose is pretty common for some other vehicles with trutracs.

Going to call eaton this morning to see what they say but I'm not sure it will be warrantied. How would you guys go about fixing this? I have a buddy who is an awesome welder and could tig the pieces back on for me and I can loctite the hell out of the bolts. There doesn't seem to be any other damage to the gears or bearings and hoping nothing is damaged inside the diff. I didn't hear any clunks or unusual noises so I don't know how long it has been like this.

Here are some pics with the areas that are missing material circled in red.

 

[Marble]

Interesting...I destroyed a locker before switching to the trutrac. Kind of three same thing happened butt it got to where it was making noise. By then it was too late.

I think I'll be pulling off my cover next month and checking everything. It's time to change to fluid anyways.

I'm not expert enough to say if the missing material matters or not. I would bring it to someone who really knows and you trust top have it checked out.

 

[AlbertD]

I had the exact same thing happen to my truetrac. When I called eaton, they asked for pictures of the damage. Upon review, they told me this was a common issue and didn't degrade or affect the performance of the unit.

I ended up running it for many more drag strip passes without an issue.


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[wicked stang]

Does anyone know what to torque the bolts to or just really tight?

Called eaton and the guy said tighten it back up and don't worry about the pieces of the housing. He said he doesn't understand how the bolts loosened up so it wouldn't be a bad idea to tack the side cover to the housing once it's bolted tight to make sure the cover doesn't shift again.

 

[Pentalab]

Has anybody used the 33 spline version of the eaton tru-trac ? That one has 4 pinion gears and a stronger housing. http://vmptuning.com/07-12-gt500-drivetrain/dts-913a701/

The 31 spline version has 3 pinion gears. http://vmptuning.com/07-12-gt500-drivetrain/dts-913a561/

Is there supposed to be blue / red loctite on those bolts ? Does eaton put any loctite on the bolts ?

 

[eighty6gt]

Our enormous POS diff shedding big chunks of metal into your diff won't affect performance! Thanks for calling! *click*

 

[07 Boss]

Tru-Tracs are tough units but there design is not conducive to hard launches. I try and steer people away from tru-tracs when planning on drag racing and always get heat for it. But Helical Gear differentials are best for road courses and because of their design are not the ideal set up for drag racing or hard launching on the street.

 

[BlueDevil]

Our enormous POS diff shedding big chunks of metal into your diff won't affect performance! Thanks for calling! *click*

"Sir, what you're experiencing is our patented time-release weight savings!"

 

[808muscle]

I had one go bad on me but it was totally different than yours. I lost pieces of metal by the teeth. Was making a horrendous whine too. It was warrantied since it was under a year old.

 

[Pentalab]

Tru-Tracs are tough units but there design is not conducive to hard launches. I try and steer people away from tru-tracs when planning on drag racing and always get heat for it. But Helical Gear differentials are best for road courses and because of their design are not the ideal set up for drag racing or hard launching on the street.

You are no doubt correct. Their 33 spline version with the 4 pinion gears might fare better, albeit you require new 33 spline axles to go with it.
Launching on sticky tires with low tire pressure will stress everything to the max. A spool etc, would be better suited for the job.

 

[Boaisy]

I had the exact same thing happen to my truetrac. When I called eaton, they asked for pictures of the damage. Upon review, they told me this was a common issue and didn't degrade or affect the performance of the unit.

I ended up running it for many more drag strip passes without an issue.


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They had the same answer for those who had the "tank track" noise when the diff wasn't under load. Eaton said it was an intended backlash in the differential, and all should be fine.

 

[ZmanM3]

time for a new diff!

 

[eighty6gt]

Yeah, blow another grand on a wave trac.

I may go to a detroit locker if my truetrac packs it in.

 

[skwerl]

I'm going to say that the end of the 'cup' that broke off has no function other than just being part of the housing. If the mounting bolts loosened and it wobbled around, breaking off the outer lip slightly then that still has nothing to do with the business end of the differential. I agree with cleaning it up, putting some thread locker on the mounting bolts and running it. That is, unless there is other damage elsewhere that you haven't shown us.

 

[ZmanM3]

I have a detroit locker, and I can't say that I exactly love it. I hate how it locks and unlocks while I'm doing slow turns in parking lots. other then that its good.

 

[eighty6gt]

I'd probably like that. Bang, ping, screech!

 

[ZmanM3]

More annoying then anything, isn't really loud.

 

[07 Boss]

Spools are good for track cars but driving on the road sucks. Plus they power the inside wheel while turning which is not the most conducive for street driving. For a strip/street car I always liked a good LSD like the Auburn Pro, Eaton Posi, or yukon Duratrac(?). Auburn has a nice electric locker that acts as a standard LSD when unlocked. All other lockers run an open diff when unlocked.

 

[Marble]

I have a detroit locker, and I can't say that I exactly love it. I hate how it locks and unlocks while I'm doing slow turns in parking lots. other then that its good.

I had one and felt the same about it. ended up breaking springs in it which caused all sorts of stability issues at the track. Eventually the bolts holding the ring gear sheared off and the pieces floating around ruining everything but the axles.

 

[wicked stang]

Pulled it all apart and everything else looked good. Just cleaned/smoothed the busted edges and replaced the bolts on both sides with new ones and loctite. The bolts didn't seem to have loctite on them on the side that loosened up but there seemed to be some blue loctite on the other side.

Got it back together and running tonight and everything seems fine so far. I will be pulling the cover again in a couple weeks to check it. I almost wish I had the side plates tacked on, my buddy is a really good welder and could have done it for me.