Posi units

[JumpinJim]

I'll jump in,
I installed the Eaton Tru-Trac in my '68 F250, had to change the axles from 16 spline to 30 spine. Not many miles on it at this point but I have no complaints- very smooth, quiet.
36" 900-16's, 4:10, C6, 450ci 427.
Jim

[AlanCasida]

I posted a similar question on the Rocky Mountain Race Week FB page asking about running a Truetrac in a heavy car with a manual transmission. The comments were mixed, some said they had no problems (so far) and others said they destroyed theirs and one person said he destroyed his Moser Wavetrac as well. One guy posted a pic of the worm gears in his after pulling it apart. It was in a #3700 car with a 6 speed and 700hp. It made me rethink running mine and I may swap back to a Detroit Locker. I am not running that kind of power but I will be in a #4300 car. I just don't want to be sitting in the pits at Port Allen, La with a rear end full of destroyed worm gears.

[sixty9cobra]

I'm running a Tru Trac many street miles 411 rear TKO 600 and 600 hp no problems in 8 yrs. even rolled the rear at Beaver still fine. I bought it from Brent with Moser axels and a Strange case.

[DuckRyder]

I know this is a little late.

I have a true trac in a 9" its vey unobtrusive until you hammer the loud pedal.

You will get vehement arguments on lube, it is difficult to find lube without AF any more. FWIW i run Delvac 1 in mine.

[Stangman]

So today I installed a true trac unit with my buddy. Now when I was making turns I was having some clutch noises like I needed more posi friction lube. Well when I got it apart and found a ring gear bolt on the bottom of the housing and the other bolts loose and falling out well I couldn’t believe it. I had it done by a very reputable shop. Well I just don’t understand why you can’t get anything done properly anymore. I wish I new how to post pics. I was literally one pass away from catastrophy. Well all together now and quiet. I only have about 5 miles on it because it was just starting to drizzle. It’s gonna rain for a few days so I will drive it to work on Tuesday which is about 12 miles each way will know for sure by then if it’s good but I’m not anticipating any problems. Thanks for the posts and answers.

[jmlay]

Sorry to hear about your misfortune!

Detroit True Trac instructions say Dino oil and no friction modifier. They are specific for a reason.

[Stangman]

Yes put Lucas 80-90 Dino oil no modifier. Keeping fingers crossed.

[gregb]

When I had the Truetrack installed in my third member, I asked what to use, said all they use for those is Torco, 85-140.  I thought that's kinda heavy, but went with the recommendation.  Bill Thomas enterprises, all he does is differential work.  Figured he knows a thing or two.  I'm sure the 85-90 version would probably be just fine. 

[Stangman]

When you buy it it tells you to only use 80-90 Dino oil. They say they haven’t done enough testing using synthetic to make it an option. Maybe you could get away with it but I guess for the time being I’m gonna follow the recommendations.

[Stangman]

Just to follow up I drove it to work the other day and all went pretty well I thought I heard a little whine on the way to work but only for one decel. On the way home I didn’t hear any noises. Does anybody think I should change the fluid after a bit. I figure I will leave it in till after the reunion then change it.