How to change rear end fluid?
Thread Starter
Melting Slicks
Joined: Oct 1999
Posts: 2,501
Likes: 177
From: Houston, Texas FEAR THE BONES
2023 C5 of the Year Finalist - Modified
How to change rear end fluid?
I know there is a drain plug, but do you have to suction the remaining fluid out? Also, how to you get the new fluid in? Special tools? Mine hasn't been changed in about 40,000 miles :nonod:
[Modified by 94vette, 9:48 AM 6/7/2002]
[Modified by 94vette, 9:48 AM 6/7/2002]
Thread Starter
Melting Slicks
Joined: Oct 1999
Posts: 2,501
Likes: 177
From: Houston, Texas FEAR THE BONES
2023 C5 of the Year Finalist - Modified
Re: How to change rear end fluid? (STL94LT1)
drain plug, fill plug... WTFD?? ;) :lol: I guess I can pick one of those up at the local auto parts store?
Any recommendations on fluid? Synthetic, Red Line, other? I know I need one bottle of posi additive.
Any recommendations on fluid? Synthetic, Red Line, other? I know I need one bottle of posi additive.
Le Mans Master
Joined: Dec 1999
Posts: 8,540
Likes: 1
From: And on the fifth day, subpoenas were served to Obama senior staff
Re: How to change rear end fluid? (94vette)
Some oils already have the posi additive, check with the brand you buy.
You need a short 3/8" allen wrench for the fill plug and a pump to remove the old oil and install the new oil.
You can order a new fill plug from Chevy, but not sure what you mean.
You need a short 3/8" allen wrench for the fill plug and a pump to remove the old oil and install the new oil.
You can order a new fill plug from Chevy, but not sure what you mean.
Melting Slicks
Joined: May 2002
Posts: 3,424
Likes: 1
From: Tucson Az
St. Jude Contributor
Re: How to change rear end fluid? (PeteL)
If you ever have the rear end out of the car, it's a very simple job to drill & install a drain plug (really just the bottom carrier bolt) this will allow you to drain old fluid (it's slow but works). I would recommend valvoline synth 85-140 with two little bottles of G.M. limitted slip additive. Change intervals should be every 10 to 15,000 miles unless you race alot, the clutch packs take a real beating. Picking up my new Dana 44 with 4.10 gear set this afternoon. Don't know how the h--- i'm gonna take it easy for 200 miles for break-in ? ? ? ?
Eddie in Tucson :smash: :smash: :smash: :smash:
[Modified by edsalinas, 6:35 PM 6/10/2002]
Eddie in Tucson :smash: :smash: :smash: :smash:
[Modified by edsalinas, 6:35 PM 6/10/2002]
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Racer
Joined: Dec 2001
Posts: 452
Likes: 2
From: Lynnfield MA
Re: How to change rear end fluid? (94vette)
When you go to the auto parts store, buy a cheap hand pump.
It can be used both to suction out the old fluid, and pump the new
fluid from bottle into the diff. Also very useful for filling the tranny.
It can be used both to suction out the old fluid, and pump the new
fluid from bottle into the diff. Also very useful for filling the tranny.
Safety Car
Joined: Nov 2001
Posts: 3,753
Likes: 191
From: Orange County California
Re: How to change rear end fluid? (SilvaDragon)
I drilled and tapped my own drain plug. Maeks this job much easier. Just like a oil change now. I change mine 1 time a year. That equals about 11,000 miles for me. Any more than that if not racing is overkill.
Le Mans Master
Joined: Dec 1999
Posts: 8,540
Likes: 1
From: And on the fifth day, subpoenas were served to Obama senior staff
Re: How to change rear end fluid? (edsalinas)
Not true, the additive helps protect the clutch material.
Eddie
Eddie
Melting Slicks
Joined: May 2002
Posts: 3,424
Likes: 1
From: Tucson Az
St. Jude Contributor
Re: How to change rear end fluid? (PeteL)
Dr. Watson, I believe we have a real debate going here ! ! ! Limitted slip additive is essential for racing, here's why. The clutchs are being used more
dramatically in cornering conditions. During straight-aways they (clutchs) are not. The additive helps in this area of concern. To reduce chatter-which inturn creates heat-which in turn causes distruction. So unless one is prepaired to rework the rear end after every 2 or 3 races, well you can take it from here........... All in fun...
Eddie :cheers:
dramatically in cornering conditions. During straight-aways they (clutchs) are not. The additive helps in this area of concern. To reduce chatter-which inturn creates heat-which in turn causes distruction. So unless one is prepaired to rework the rear end after every 2 or 3 races, well you can take it from here........... All in fun...
Eddie :cheers:
Drifting
Joined: May 2001
Posts: 1,295
Likes: 2
From: Surprise Arizona
Re: How to change rear end fluid? (edsalinas)
I used compressed air to get the new fluid in to my gearbox and OD unit. They could both be drained.
Get some clear tubing from the hardware store. I think it was 3/8" OD tube but I dont quite remember. (Im over 40 now) Then drill a hole in the side of a gear lube bottle at the highest point on the neck of the bottle, make the hole just big enough to squeeze the tube in. Put one tube in this hole on the side, push it just a slight ways in. Use this tube to apply pressure to the bottle. Cut the nozzle off of the bottle top just big enough for another tube to slide in to it snugly. Run this tube to the very bottom of the bottle. Then apply some air pressure to the inlet tube and watch the lube flow to the case through outlet tube. It works very well, is cheap, reusable, and filled the case up very quickly.
Without a drain plug on the Dana 44 we will still need a pump.
Get some clear tubing from the hardware store. I think it was 3/8" OD tube but I dont quite remember. (Im over 40 now) Then drill a hole in the side of a gear lube bottle at the highest point on the neck of the bottle, make the hole just big enough to squeeze the tube in. Put one tube in this hole on the side, push it just a slight ways in. Use this tube to apply pressure to the bottle. Cut the nozzle off of the bottle top just big enough for another tube to slide in to it snugly. Run this tube to the very bottom of the bottle. Then apply some air pressure to the inlet tube and watch the lube flow to the case through outlet tube. It works very well, is cheap, reusable, and filled the case up very quickly.
Without a drain plug on the Dana 44 we will still need a pump.
Race Director
Joined: Dec 2000
Posts: 17,786
Likes: 5
From: Florida
Re: How to change rear end fluid? (94vette)
Simple.....a $30 MityVac pump. Use the suction and a reservoir to suck the old gear oil out.....reverse the suction to push the new stuff back in. I had a small reservoir, so I had to stop quite a few times to empty/fill the container. But it worked, was easy and the pump can be used for other purposes (bleeding brakes, checking vacuum fittings, etc.). :)
Le Mans Master
Joined: Dec 1999
Posts: 8,540
Likes: 1
From: And on the fifth day, subpoenas were served to Obama senior staff
Re: How to change rear end fluid? (edsalinas)
Dr. Watson, I believe we have a real debate going here !
OK, so you must be either Prof Holmes or Mr Bell :lol:
We all know it has to slip, a little; as in "limited slip". Too much sperm whale oil (substitute), and it slips too much, and is not longer "limited slip" and only driving on one wheel as in "open diff". And we don't want that, racing , as we want traction.
So I guess I don't believe that two bottles of limited slip additive is the best of all possible worlds. We need some slip, but we also want the clutches to lock when needed.
So I think we agree to a point. Too much slipping also causes wear. Too little additive causes chatter and also wear. My point is for the best performance you have to get the mix right. I think the one bottle is good for street use where folks don't wan't to worry about the chatter (causes service visits under warranty). A little chatter is not doing much harm. perhaps not as much as too much additive!
Back to Alexander. :D
Melting Slicks
Joined: May 2002
Posts: 3,424
Likes: 1
From: Tucson Az
St. Jude Contributor
Re: How to change rear end fluid? (Vic'89)
quote;
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Ok, so you must be either Prof Holmes or Mr Bell.
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Thanks for the Fun, love to start my day with a chuckle ! ! ! ! Yes, I think we do agree, the general belief (after a few phone calls) is one little bottle of additive is plenty for a D36, or D44...... As for the fella that wants to simply remove the cover to drain the fluid, we all wish it were that easy ! ! ! ! ! To remove the cover (called the DIF CARRIER in the book) you drop the entire rear suspension, not that big a job, but plan on an entire weekend, depending on the beer consumption . . . . . . . Ha Ha
Back to you Dr. Watson :jester :p: :flag
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Ok, so you must be either Prof Holmes or Mr Bell.
-----------------------------------------------------------------------------------------------------
Thanks for the Fun, love to start my day with a chuckle ! ! ! ! Yes, I think we do agree, the general belief (after a few phone calls) is one little bottle of additive is plenty for a D36, or D44...... As for the fella that wants to simply remove the cover to drain the fluid, we all wish it were that easy ! ! ! ! ! To remove the cover (called the DIF CARRIER in the book) you drop the entire rear suspension, not that big a job, but plan on an entire weekend, depending on the beer consumption . . . . . . . Ha Ha
Back to you Dr. Watson :jester :p: :flag
Instructor
Joined: Apr 2002
Posts: 243
Likes: 0
From: Hockessin DE
Re: How to change rear end fluid? (Vic'89)
i dont think so. theres a whole bunch of suspention crap in the way. this is one area where my Z28 is better than my C4, you can just remove the diff cover
