Amsoil Severe Gear 75-90 vs Factory Fill

[01PontTa]

Hello, Like the title states I had the factory fill GM grape scented oil made by Blue ester 75-90 in my 01 Firebird. Rear was quiet but started to get a rubbing sound at the right rear, the right axle bearing and axle wore. Axle was replaced with a Dorman axle kit and Valvoline 80-90 Durablend. Rear was nice and quiet again, no noises what so ever BUT I didn't like the fact that the Dorman axle was made in India and looked poorly made. SO I bought a GM axle, had the axle installed along with Amsoil 75-90.

Immediately after this the ring and pinion started whining both on power and coast. Also on a steady light throttle you can hear the gears rubbing against each other. It starts doing this after about 10 miles or so of driving after the oil warms up, cold its completely quiet. Now I know putting the Valvoline 80-90 back in will solve this problem BUT I WANNA KNOW WHY?????????????

 

[Black_Thunder]

Maybe its foaming up?



Don't know what else to tell ya I've never used it.


I've only used Valvoline 75w90 or Mobil.

or Supertech/Mobil 75w140


Never had any significant gear whine with either.

 

[chazzone]

II swapped an 8.8 and D-35 from a '92 Explorer into my BII more than 150,000 miles ago, and filled with Severe Gear.

I have no idea how many original miles they had.

It is my work truck, and I pull a trailer and a boat, and get into some pretty nasty mud from time to time.

No issues what so ever.

 

[JHZR2]

Dont GM Diffs have issues with lube holes that allow lube to get down to the ends of the axle or not? Thought that the OE gaskets blocked the holes that allowed the lube flow.

After the replacement, how much clunking and whirring has to do with bearing preload and gear intrfacing (i.e. istallation) vs fluid?

 

[Whitewolf]

You should use the DEXRON 75-90 part #88863089, it's a much better product.

 

[buck91]

Are you sure the installer didnt mess with the carrier and pinion shims?

 

[SwampSurvivor]

They have scented gear oil?

 

[The_Eric]

Originally Posted By: Whitewolf
You should use the DEXRON 75-90 part #88863089, it's a much better product.


I'm curious what makes it a better product?

 

[01PontTa]

The gears were not touched, only the axle was changed ans Amsoil Added.

Chazzone what weight Severe gear did you use?


I'm changing it back to Valvoline BUT I still want to know why this Amsoil makes the gears so noisy, it doesn't make sense unless the Amsoil is WAY off the mark in some way.

 

[Donald]

Originally Posted By: The_Eric
Originally Posted By: Whitewolf
You should use the DEXRON 75-90 part #88863089, it's a much better product.


I'm curious what makes it a better product?



+1 - I believe the Amsoil SVG (properly spec'ed) is one of the best gear oils available. Period.

 

[01PontTa]

Its spec'ed for this rear, there is no other noises just the pinion-ring gear noise. I'm a experienced wrench, been doing this for many years. You can listen to the pinion-ring gear noise and predict where the throttle is. Very odd to say the least.

 

[MolaKule]

Quote:
SO I bought a GM axle, had the axle installed along with Amsoil 75-90.


Was this a new axle or a used axle?

Quote:
Are you sure the installer didnt mess with the carrier and pinion shims?


If this was a used axle, shims may have been worn and gear preloading may not be correct.

 

[01PontTa]

I'm the installer and no shims get touched. What would it matter if the axle was new or used? As long as its in good condition. The axle simply slides in and out, there are no shims involved? where is this info shim coming up for the axle? I'm a long experienced advanced tech, trust me its ring and pinion noise from the oil. As soon as the oil warms up the ring-pinion starts to sing. If I put Valvoline or the factory fill back in its DEAD QUIET.

How many times must I post nothing was touched in the rear except sliding a axle in and out and adding Amsoil? With the Valvoline in its dead quiet, this isn't the 1st time I had this happen with Amsoil 75-90 svg. This time I want a real reason why. Last time I was told to use the 110 svg. Well that's not the spec for this rear, the 75-90 Amsoil should run just as quiet as any other oil.

There has to be a logical answer to this problem. I suspect the oil can't handle the small ring gear loading. This has a tiny 7.5 ring gear. Air temps in the 60's easy driving 40-55 mph.

I called Amsoil let them figure it out.

 

[cpayne5]

Originally Posted By: Miller88
They have scented gear oil?


Yep, sure do.

 

[01PontTa]

Originally Posted By: Donald
Originally Posted By: The_Eric
Originally Posted By: Whitewolf
You should use the DEXRON 75-90 part #88863089, it's a much better product.


I'm curious what makes it a better product?



+1 - I believe the Amsoil SVG (properly spec'ed) is one of the best gear oils available. Period.
What makes you believe this?

 

[01PontTa]

By the way GEARS don't get preload, bearings do. The info I'm getting here really worries me you guys really are just guessing.....I need a REAL answer.

 

[MolaKule]

Was this a complete axle Assembly (with differential) or did you simply replace one axle SHAFT and bearing?

When some people say "Axle" they may mean the complete rear differential (including the axle) assembly.


http://www.bernardembden.com/xjS/diff/index.htm

http://www.youtube.com/watch?v=zV-1-cGhNnQ

http://www.youtube.com/watch?v=jh25DUyCWY8

Did this differential have a "C" clip and did you replace the C clip with a new one?

instructor.mstc.edu/.../Ring%20and%20Pinion%20Adjustments.ppt

I question, with what you described, that it really is the pinion bearing making a noise.

I.E., if you changed out the axle, bearing and seal, why would the pinion bearing suddenly start making noise?

I do not see a cause and effect for what you described.

 

[MolaKule]

Quote:
Immediately after this the ring and pinion started whining both on power and coast. Also on a steady light throttle you can hear the gears rubbing against each other. It starts doing this after about 10 miles or so of driving after the oil warms up, cold its completely quiet.


Just for clarification, Gears mesh, they don't rub against each other.

Questions about Shim Kits

 

[01PontTa]

WOw sorry I posted up forget about it,,,,you don't have a clue.

 

[dailydriver]

Originally Posted By: 01PontTa
Its spec'ed for this rear, there is no other noises just the pinion-ring gear noise. I'm a experienced wrench, been doing this for many years. You can listen to the pinion-ring gear noise and predict where the throttle is. Very odd to say the least.


ALL 10 bolts will do this eventually.

How many miles on the ring and pinion?

Did it see any sticky rear tire (drag radials or gummier) clutch drop hard launches, or hard launches/60 foots on a prepped/sticky drag strip pad during it's lifetime???

IF it still is noisy after the mineral Valvoline install, I would try a good, synthetic, HIGH cSt @100*C 75W-140 (like Red Line, L.A.T., etc. IF you are turned off by, or afraid of Amsoil).

It makes no sense though, as the Amsoil SG 75-140 was the quietest fluid for my banshee on decel/coast, 3.73 geared, 10 bolt, save for the current (and CRAZY priced) Millers NT gear oil.

Did you try putting in a little limited slip friction modifier (I suggest the Motorcraft XL-3 noxious stuff), even if you still have a stock Torsen T-2 which technically does NOT require it, but which had some TSBs sent out to do just this to quiet down the 'rocks in a box' T-2 coast down noises?