btw i bought 80-90 valvoline...for the rear end and full synthetic valvoline for the transmission...

 

About a year or so ago a few guys had issues with their trutracs not operating properly (only one tire spinning at the track), and it turned out that they were using synthetic gear oil, and switching to dino gear oil cured their issues, as per Eaton's recommendation. Someone had noticed that Bill's (trever1t) trutrac was only spinning 1 tire, and he was using syn at the time, not sure if he ever switched to dino or not. At the same time, there were guys who were running syn with their trutracs without problems, kinda luck of the draw.

After a few years of believing that conventional gear oil is what Eaton recommends, it's confusing to hear that they now say it's OK. I wouldn't go by what the Vette and Viper use though, as I'm pretty sure that their differentials are G80's (at least the Vette probably is), which calls for synthetic only. The G80 uses a flyweight, latching bracket, and self energizing clutch system to lock when the wheel speed difference left to right exceeds 100 rpm, while the trutrac uses a helical gear system and locks up before wheel spin occurs. Also, above 20mph, the G80 will unlock...I believe that the trutrac will stay locked when it is operating properly, so they're different monsters.

 

I wonder if it's one of those deals where it depends on who answers the phone...just like when you call Comp 3 different times for a cam recommendation and get 3 different recommendations depending on who you talk to.

I'll see if I can find the threads where it was determined that the TruTrac should use conventional, it was a few years ago though so it may be tough. I'll try if I have the time when I get home tonight I remember that there was a big to do about it though and the recommedation not to use syn also came straight from Eaton as per one of our member's phone calls to them.

 

Id be careful with the lucas products.



click this link and check it out- some great stuff in here.......http://www.bobistheoilguy.com/images/lucas/lucas.htm

 

Yessir, bobistheoilguy rocks, I've spent many hours on that site

 

I was told that they had heard some complaints about noise when the rear end got hot in the early years and started to recommend standard oil. Then he told me that he has guys running tetras in corvettes and vipers running auto cross and they are not having any problems, "BUT" they were running oil that was $50 a quart and not cheap auto zone synthetic oils. I told them that the shop I work part time at is an Amsoil dealer and that I had ran it in everything else and was really happy with it. He said you can sure try it. IT WON'T HURT THE DIFFERENTIAL, it may just be noisy. I've had zero problems with it so far. Skeet's problems were not due to any particular type of oil...

 

i deleted my email but the guy from eaton emailed me saying use regular 80-90w oil no synthetic and no additive for the tru-trac... im sure he said it for a reason..lol

 

I don't believe that damage to the diff is a concern, it's about the trutrac functioning properly. There was a handful of guys running syn with their trutracs and getting a one wheel peel, which they cured by switching to conventional. But hey, if you're running syn and laying two strips, go with it. Personally, I try to run syn wherever possible...I like Amsoil too, I'm running it in my engine now. The only places that I don't have syn is in the trans as Andy and Vince at FLT said no way, gotta run dino, and in the power steering lol. The engine, and both front and rear diffs currently have syn in them. Eventually I'm planning on a trutrac which I was sure that I was going to run conventional in due to what I've learned here in the past, but if there's this much confusion as to what fluid goes in there, and conflicting information coming straight from Eaton themselves, I may just say screw it and go with an Auburn posi lol

 

I definitely think the trutrac is the best posi on the market. I think that Eaton has said screw it, tell everyone to run conventional. Probably cause its more consistent, where synthetic oils can very more in quality. Too many people think that Walmart full synthetic has all the same properties as Royal Purple and the extra cost is just cause it's brand name. Its just not true. I believe that people were buying the cheap synthetic diff oil thinking, It's gotta be better then conventional. And thats not always the case...

When I can run amsoil at a 100 to 1 ratio in my two strokes go longer between rebuilds, it makes me a believer in it as a product. Do you think I would try that with Autozone's synthetics? Same policy goes for my truck, you get what you pay for...

 

I couldn't agree more, I'm running Amsoil in my truck, my ex-wife's Toyota Matrix, and my mom's Toyota Solara. It's nice to only have to change their oils once a year, and the oil analysis that I got back from both of the Toyota's looked good aside from some excess dirt.

And yea, I'm still set on a trutrac, just messin around about the Auburn (not that there's anything wrong with an Auburn)

The big question is...is your trutrac locking em both up running the syn? As I mentioned, seemed like it was hit or miss as to who's did and didn't function properly with the synthetic gear oil. I've been too busy hopping around between a few threads here to go searching for the old threads that I was referring to earlier...