Help identifying this differential fluid
Thread Starter
Pro
Joined: Apr 2011
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From: Canada
Help identifying this differential fluid
Guys, I am leaning towards putting the conventional fluid into the car differential from the factory. I have some numbers of Rear Axle Lubricant, 80W-90 Gl-5. Apparently GM started with #12345977 and it was changed to #89021669 and today it is #89021670. I called Lordco and a GM dealer and they said they only carry #89021670 now, and I am trying confirm if this is non-synthetic and if this is close to the original fluid and okay to put into my 1989 differential ??? Thank you for any words of wisdom. (Updated: I chose a differential fluid. See post #9).
Last edited by ~ Anno Domini; Aug 14, 2019 at 10:42 AM.
Melting Slicks
Joined: Dec 2004
Posts: 2,656
Likes: 635
From: Dallas TX
Yea you could put the cheapest **** from oreilly in there plus some lsd additive and you would be fine.
The d36/d44 is not a high tech diff... Its a jeep diff lol. Those guys run **** in theirs and have no problems.
The d36/d44 is not a high tech diff... Its a jeep diff lol. Those guys run **** in theirs and have no problems.
Drifting
Joined: Sep 2014
Posts: 1,579
Likes: 59
From: Trieste Italy
Guys, I am leaning towards putting the conventional fluid into the car differential from the factory. I have some numbers of Rear Axle Lubricant, 80W-90 Gl-5. Apparently GM started with #12345977 and it was changed to #89021669 and today it is #89021670. I called Lordco and a GM dealer and they said they only carry #89021670 now, and I am trying confirm if this is non-synthetic and if this is close to the original fluid and okay to put into my 1989 differential ??? Thank you for any words of wisdom.
Last edited by Christi@n; Aug 8, 2019 at 09:19 AM.
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Joined: Apr 2011
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From: Canada
Thank you all for your input. To be honest, I don't want to overthink what fluid to put in the differential, but it is hard not to. As I began researching this topic I found there is no general consensus on what fluid to use. Some say synthetic, others say non-synthetic, then there are the brands. I have not taken a position. My view is that if a differential fluid works for you that is great and I want to know about it so I can then make a decision on what to do, which led me to the question of can this non-synthetic Rear Axle Lubricant, 80W-90 Gl-5 (part # 89021670) be used in a 1989 Corvette. :-) Thank you.
Last edited by ~ Anno Domini; Aug 8, 2019 at 09:13 AM.
Drifting
Joined: Sep 2014
Posts: 1,579
Likes: 59
From: Trieste Italy
Thank you all for your input. To be honest, I don't want to overthink what fluid to put in the differential, but it is hard not to. As I began researching this topic I found there is no general consensus on what fluid to use. Some say synthetic, others say non-synthetic, then there are the brands. I have not taken a position. My view is that if a differential fluid works for you that is great and I want to know about it so I can then make a decision on what to do, which led me to the question of can this non-synthetic Rear Axle Lubricant, 80W-90 Gl-5 (part # 89021670) be used in a 1989 Corvette. :-) Thank you.
Anyway what I do in order to choose the right fluid is to read the fluid spec and type on owner manual and search on the web for the same spec and type
You will be right
Last edited by Christi@n; Aug 8, 2019 at 09:26 AM.
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Thread Starter
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Joined: Apr 2011
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From: Canada
UPDATE: I ended up putting in conventional, non-synthetic Mobil 1, 80W/90 GL5 gear oil with the GM limited slip additive part number 992694. I went to a local GM dealer and bought one 4 ounce bottle of the slip additiveI for $10.58 Canadian. Then drove a few miles to a Mr. Lube where I knew one of the guys there also had a C4. He changed the differential fluid and put in the GM additive. Mr. Lube provided the conventional Mobil 1 fluid. It cost $89 dollars + $10.58 for the additive. The car drives fine. Thank you for your help.
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I agree and would like to do it and save the money Christian, but my e-brake cable is seized and needs to be fixed first. I also need to buy a couple of ramps to drive the car up to get under it. That e-brake cable is a whole other puzzle and post for another day when I feel emotionally up to tackle it, lol.
Safety Car
Joined: May 2001
Posts: 4,759
Likes: 1,647
From: Fairfax Virginia
One suggestion you might try before you attack the emergency brake cable...
Motorcycles use cables for throttles, clutches and brakes. They ALL need to be lubricated or they fail fast. In the motorcycle world there is a set designed to lubricate the cables. The main part goes over the end of the cable allowing you to squirt oil into it. It is your choice what oil type to use but I would recommend KROIL OIL as it is the very best at breaking loose corroded fittings and such. Use Kroil or some other penetrating oil and spray it into that cable several days in a row BEFORE you attempt to work on them. Heat and Kroil Oil work great for breaking anything free. It doesn't have to be heated with a torch either, find a hot air gun or borrow a Hair Drier and apply the heat and then more oil. If you do this several times the likelihood of the cable releasing is much greater!
Here is a picture of the main part of the cable lubing system:
Once you have one of these you can find many uses for them. The second part they give you is a can of lubricant. You need to penetrate the corrosion to get the cable free with something stronger.
Don't Fear the Brakes!
Best regards,
Chris
Motorcycles use cables for throttles, clutches and brakes. They ALL need to be lubricated or they fail fast. In the motorcycle world there is a set designed to lubricate the cables. The main part goes over the end of the cable allowing you to squirt oil into it. It is your choice what oil type to use but I would recommend KROIL OIL as it is the very best at breaking loose corroded fittings and such. Use Kroil or some other penetrating oil and spray it into that cable several days in a row BEFORE you attempt to work on them. Heat and Kroil Oil work great for breaking anything free. It doesn't have to be heated with a torch either, find a hot air gun or borrow a Hair Drier and apply the heat and then more oil. If you do this several times the likelihood of the cable releasing is much greater!
Here is a picture of the main part of the cable lubing system:
Once you have one of these you can find many uses for them. The second part they give you is a can of lubricant. You need to penetrate the corrosion to get the cable free with something stronger.
Don't Fear the Brakes!
Best regards,
Chris
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Joined: Apr 2011
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From: Canada
Excellent suggestion, ctmccloskey. I would definitely try lubricating first. Thing is, I think this brake cable problem may be a length issue. I had a shop put in a new cable and the car would very slowly move on a hill when I pulled the handle up. It would not hold the car. The shop said they did everything right, so I eventually stopped using it and it seized. I have a feeling this may have to do with the length of the aftermarket cable not being the exact same length as the original rear cables, but my brain hurts and I don't want to chase this rabbit right now. Also wanna keep this thread on topic. I will try your tip though in the future. TY.