Changing Rear Differential Fluid

[Z4me]

Going to change the fluid soon, did you use a torque wrench or just hand tighten? I'm new to doing it yourself mode, hence this dumb question, do you have a washer associated with the bolt that should be replaced. If so do you purchase from your Chevy dealer?
I purchased some race ramps to make changing the oil,differential fluid easier to do. My driveway has mild incline so I plan on backing the car on to the ramp till it's level. Then put the emergency brake on and blocks around the tires to keep the car in place. This way I should have some extra room to work under the car for this fluid change and still keep the car fairly level.
For the oil change I'll move the car fully onto the ramp.
Thx for the good info btw.

[K1SSRSS]

Originally Posted by Z4me

Going to change the fluid soon, did you use a torque wrench or just hand tighten? I'm new to doing it yourself mode, hence this dumb question, do you have a washer associated with the bolt that should be replaced. If so do you purchase from your Chevy dealer?
I purchased some race ramps to make changing the oil,differential fluid easier to do. My driveway has mild incline so I plan on backing the car on to the ramp till it's level. Then put the emergency brake on and blocks around the tires to keep the car in place. This way I should have some extra room to work under the car for this fluid change and still keep the car fairly level.
For the oil change I'll move the car fully onto the ramp.
Thx for the good info btw.

If you have a torque wrench it's a good practice to look up the torque specs and use it when starting out, but personally I don't feel the drain plugs on the diff are necessary to have an exact torque. I don't remember for sure if there was a washer on these or not, but no you shouldn't need to replace it if there is.

[Garndog]

There is a rubber washer. I just cleaned it up and tightened ( goodntight )

[bluecam805]

In going to change mine tomaro. I'm going with the Lucas synthetic 75-90. Lucas should be good right? And do u just squeeze in the whole .9L of it? Of does it have to be exact volume?

[Red2014SS]

Question - Is the diff housing made of aluminum? If so, should I use an anti-seize on the threads of the steel plugs?

[wally mayfield]

sure, your heads are aluminum and the spark plugs aren't..

[Red2014SS]

Originally Posted by wally mayfield

sure, your heads are aluminum and the spark plugs aren't..

Sure? Sure what? Have you ever pulled aluminum threads out of a manifold because they were stuck to a steel bolt? I have. It's no fun.

[wally mayfield]

Originally Posted by Red2014SS

Sure? Sure what? Have you ever pulled aluminum threads out of a manifold because they were stuck to a steel bolt? I have. It's no fun.

Sorry you'll have to give me a break, I'm old..yes put some anti seize on the threads.

[revived]

Don't need any anti seize on either fill or drain bolts.

And also don't over tighten the bolts last thing you want to do... Just snug it up then give em a hit and your done.

[Cool1LE]

OK so someone correct me if I am wrong (way to many strings on this) - when using the recommended OEM fluids (V8 manual 1LE) it will take 1qt of the lube and 2.5oz of the limited slip additive that is sold in 4oz bottles?!?! really?? so slightly over half which means you don't have enough left over for the next time....

[revived]

Originally Posted by Cool1LE

OK so someone correct me if I am wrong (way to many strings on this) - when using the recommended OEM fluids (V8 manual 1LE) it will take 1qt of the lube and 2.5oz of the limited slip additive that is sold in 4oz bottles?!?! really?? so slightly over half which means you don't have enough left over for the next time....

pretty much, its really no big deal... you did spend a lot of money on the car why not treat it right.

Its good having extra fluid.... you can use it to.

1. flush the sludge out

2. refill if you don't have a good pump or way to put the fluids in.


if pump is a issue go to your local marine boat shop and purchase a outboard gear lube pump. There cheap and work great.. I bought 2 bottles of RP w/ firction modifier already in it. The second bottle was handy so I could flush my diff with the extra fluid.

[GMTool]

Originally Posted by Cool1LE

OK so someone correct me if I am wrong (way to many strings on this) - when using the recommended OEM fluids (V8 manual 1LE) it will take 1qt of the lube and 2.5oz of the limited slip additive that is sold in 4oz bottles?!?! really?? so slightly over half which means you don't have enough left over for the next time....

First time I did mine using OEM fluids I put 2.5 oz's in per owners manual. Then after a while my rear end started making noise when backing up and turning steering wheel. Took it to dealer and the mechanic that works on my car said I should of put the whole 4 oz bottle in. So he changed the fluid and no problem after that. I changed the fluid myself again last spring with OEM fluids and put the whole 4 oz bottle in first then filled it up with the 1 qt of lube. Drove it around did some figure 8's in a parking lot. No problems.

[SixSpeeder]

I had my first oil change done today at 1000 miles, and also had them change the dif fluid while they were at it. The differential lubes the dealer put in were part numbers:

88900401 - Genuine GM Fluid 75W-90 Synthetic Axle Lubricant - 1 Quart
88900330 - Genuine GM Fluid Limited Slip Axle Lubricant Additive - 4 oz.

[billbathgate]

Hey bud nice post just wanted to ask a couple questions .did u use lock tight or Teflon tape on the drain and fill plugs and how much exactly should u pour in ..I think I'm a go with the royal purple stuff ...who do you know if it's not to much or to little
I appreciate the help....