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RESOLVED - too much slack on carrier.... More Eaton True Trac horror noise...

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Duane Black

Curbs go brrrppp
589
430
Exp. Type
Time Attack
Exp. Level
5-10 Years
Durham, NC
Alright car gurus....

Short version - I installed an Eaton True Trac after my Torsen failed. I figured this was the carrier but since its primarily when turning right, I pulled it back down and put in 2 new wheel bearings. Same noise.

The noise doesn't totally go away on throttle, but it changes and gets much quieter. In a left turn, its virtually dead silent.

I cant find anyone online with an issue like this so.... need whatever help I can get.

The ring and gear was kept, and the lash is .010 to .012 in 4 spots. the books call for .008 to .012. I did install all new pinion bearings and races, and the pinion doesnt move at a shake at least.




 

xr7

TMO Addict?
727
855
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Autocross
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10-20 Years
Minnesota
I would guess the used gears may be the problem. Generally when reusing gears its a real crapshoot to get them set up right. The best recommendation is to measure backlash before disassembly and to check the contact pattern of the gears. With a new ring gear carrier and of a different manufacturer its damn tough. The only other idea is if something is touching the rear end housing in the right hand turns. Usually noises that change with throttle manipulation is the gears, bad gears or bad bearings.
 

Duane Black

Curbs go brrrppp
589
430
Exp. Type
Time Attack
Exp. Level
5-10 Years
Durham, NC
I would guess the used gears may be the problem. Generally when reusing gears its a real crapshoot to get them set up right. The best recommendation is to measure backlash before disassembly and to check the contact pattern of the gears. With a new ring gear carrier and of a different manufacturer its damn tough. The only other idea is if something is touching the rear end housing in the right hand turns. Usually noises that change with throttle manipulation is the gears, bad gears or bad bearings.
I've never heard of a gear being an issue when you turn though... thats kind of an "all of the time" issue.
 

xr7

TMO Addict?
727
855
Exp. Type
Autocross
Exp. Level
10-20 Years
Minnesota
I've never heard of a gear being an issue when you turn though... thats kind of an "all of the time" issue.
Perhaps there are two problems? If something is touching the diff housing when you turn to the right the sound will really travel thru the car. Does the sound quit as soon as you start to straighten out? I would find a big empty parking lot. Get somebody to drive the car and then ride in the back with the rear seat out and then listen for the noise, a mechanics stethoscope may help you pin point the noise.
 
1,291
1,296
Exp. Type
HPDE
Exp. Level
5-10 Years
Lenoir City TN
I can't give any help on this one but interested in the outcome. I am planning on swapping the tracloc for a truetrac in a couple of weeks.
 

Duane Black

Curbs go brrrppp
589
430
Exp. Type
Time Attack
Exp. Level
5-10 Years
Durham, NC
I would guess the used gears may be the problem. Generally when reusing gears its a real crapshoot to get them set up right. The best recommendation is to measure backlash before disassembly and to check the contact pattern of the gears. With a new ring gear carrier and of a different manufacturer its damn tough. The only other idea is if something is touching the rear end housing in the right hand turns. Usually noises that change with throttle manipulation is the gears, bad gears or bad bearings.
I've never heard of a gear being an issue when you turn though
 

Duane Black

Curbs go brrrppp
589
430
Exp. Type
Time Attack
Exp. Level
5-10 Years
Durham, NC
It was a dumb installer error. i didnf pack enough shims and it was shifting.

Ironic... the torsen was a longer unit ans has a big stack of thin spacers to make it work.

The two factory shims worked PERFECT
 
80
66
Exp. Type
HPDE
Exp. Level
Under 3 Years
Houston, TX
I am glad you solved your issue!

BTW, I just personally installed mine ~1 month ago and noticed that there is slightly more differential flange play than with my oem diff with TracLoc. The flange turns ~3/16" freely before the wheels move. Do you notice this as well? My backlash is averaged at 10.5 thou in 4 spots.

My thought is that since there are more gears inside the eaton than the TracLoc, those extra tolerances add up to more flange play even if backlash is set within spec.

What do you think?

I have not driven my 'stang at the track since the install, but in tight turns I feel as if the rear is steering and it simply feels amazing!
 

Duane Black

Curbs go brrrppp
589
430
Exp. Type
Time Attack
Exp. Level
5-10 Years
Durham, NC
Ive experienced that turning out of a driveway.. like woah, am I going to need to soften a sway bar?

They notoriously have a lot of "slop." Once sealed it feels like you have about an inch of lash in the pinion, but thats just how they are
 
6,675
8,776
future reference..

 
80
66
Exp. Type
HPDE
Exp. Level
Under 3 Years
Houston, TX
Ive experienced that turning out of a driveway.. like woah, am I going to need to soften a sway bar?

They notoriously have a lot of "slop." Once sealed it feels like you have about an inch of lash in the pinion, but thats just how they are
Alrighty, great to hear that you have a similar opinion and situation about the slop. I have a 6 puck clutch and the gears/bushings/control arms slap like crazy if I don't pump the throttle till I get it going from idle in 1st or reverse.

I feel that lap times at my home track (MSR Houston) will drop maybe up to a couple of seconds, but I have yet to see if that comes to fruition, hopefully by the first weekend in March.

BTW, all hail the V6!! :D
 
80
66
Exp. Type
HPDE
Exp. Level
Under 3 Years
Houston, TX
future reference..

Bookmarked!
 

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