darcman

I did do some reading, just thought I would ask anyways
So its 75/140 + friction modifier for the dif


I always figured my dif was kinda whiney, I am getting up to around 50K miles so I thought I would change oil. It definitely seems to be getting more whiney. I lowered my car with the steeda sport springs, I never did the upper control arm. People said that with a 1/11/4 drop it wasn't necessary, but I got worried maybe I took out a pinion bearing by not doing the upper control arm. Anyone else with a whiney rear end fix it with a fresh gear oil change.

houtex

http://www.royalpurpleconsumer.com/products/max-gear/

Get two... or is it two and a bit more?... 1-qt bottles of that. That's what's in Awesome, and 75K later, no issues whatsoever. Then again, I ain't pulled the cover off since, but she doesn't make noise. I had to replace a right rear bearing, so I replaced both, and that's when the old stuff came out (was perfectly fine, gears were in great shape) and I put the above in. Also have RP's Synchromax in the TR3650 manual, and it surely made a difference.

That said, a whiny gear set probably isn't going to be the pinion, it's going to be the gears. If the pinion bearing is out, it's also going to leak out that pinion, most likely, so if you don't have any drips, you're good there.

I don't think the changing of the fluid will fix the whine, as that's really going to be a meshing issue, so you might want to just take the car to a reputable axle specialist and get it checked out. Or at least get it on a rack, and get a stethoscope out and figure out where it's comin' from.

For what my opinion is worth on that. Good luck, hope it helps!

darcman

Hey Houtex I might just give the gear oil a change anyways. If it fixes the whine great, if it doesn't, oh well. Its not that expensive and for all I know maybe I am down in gear oil.


I don't have any leaks. With the pinion thing...you know how it goes you hear a noise and start second guessing what might have caused that. My mustang would be the first car I have ever had any rear end problems with, if that's where the noise is coming from. No clunking or anything so that's good. I will have to report back.

Joe88xj

Thanks for the info

Joe88xj

Thanks

darcman

Well I changed the rear end gear oil with Amsoil 75W140 and the guy gave me a tube of Amsoil friction modifier. I haven't driven it on the highway yet, it may have quieted it down somewhat. I might just be getting a lot more harmonics than stock, as I have all steeda suspension, billet control arms, lowering springs, panhard rod & brace, sway bar billet end links. I will keep my ears open, just in case.


One thing though I read about guys using funnels for the gear oil. Some guys said the pumps were no good. When I bought my amsoil the guy sold me an amsoil pump pump that screws on the bottles. I am totally glad I bought the pump, worked like a hot dam and saved me a whole lot of time and grief. No leaks on the dif cover either


I grabbed this torque spec online, it was for a gasket kit and I used ultra black. I used the sequence and specs anyways it looked about right.