FYI factory diff fluid does not have LS additive
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FYI factory diff fluid does not have LS additive
Hi guys I got 2 bottles of AC Delco rear diff fluid from GM
part number in Canada 89021678
I notice from searching on here some say that this fluid "does" have LS additive already mixed in. this info is not correct and wanted to let others know
if you run the part number above you must buy the additive
here is email from gm/ac delco
Thank you for your inquiry. We have consulted with our ACDelco TAC team and they have confirmed that the ACDelco Rear Axle Lubricant/PN 89021678 is a synthetic gear lubricant. It does not contain limited slip additive. To inquire further about ACDelco products including fluids and lubricants, we suggest that you contact an ACDelco distributor.
part number in Canada 89021678
I notice from searching on here some say that this fluid "does" have LS additive already mixed in. this info is not correct and wanted to let others know
if you run the part number above you must buy the additive
here is email from gm/ac delco
Thank you for your inquiry. We have consulted with our ACDelco TAC team and they have confirmed that the ACDelco Rear Axle Lubricant/PN 89021678 is a synthetic gear lubricant. It does not contain limited slip additive. To inquire further about ACDelco products including fluids and lubricants, we suggest that you contact an ACDelco distributor.
Last edited by 1999C5JSS; Mar 3, 2015 at 11:04 AM.
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I don't think they do. parts guy at gm search my car based on Vin and said I just need rear diff fluid part number 89021678. I even asked him about additive and he said does not come up as needed.
thats when I started researching and finally just contacted AC DELCO.
Last edited by 1999C5JSS; Mar 3, 2015 at 11:22 AM.
Racer
Joined: May 2012
Posts: 330
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From: Visalia California
I just put the Mobil 1 synthetic gear oil with the limited slip already mixed in it says LS right on the bottle.
Thanks for sharing the info, I wonder how many people have used this with out the additive.
Thanks for sharing the info, I wonder how many people have used this with out the additive.
Pro
Joined: Mar 2014
Posts: 657
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From: Houma Louisiana
Thanks for sharing the info!
I recently changed my Rear Diff fluid out and was deciding between AC Delco and Amsoil. I went with Amsoil after reading many great reviews and it has the additive already mixed into it. Did some figure 8's and all is well
I recently changed my Rear Diff fluid out and was deciding between AC Delco and Amsoil. I went with Amsoil after reading many great reviews and it has the additive already mixed into it. Did some figure 8's and all is well
Melting Slicks
Joined: Jun 2013
Posts: 3,473
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From: West Virginia
Repair manual clearly says to use limited slip additive. Note however, that the manual was written before "LS" rated lubes were available.
When I did "front to back" oil changes recently, I used Mobil 1 LS - no issues as far as I can tell.
When I did "front to back" oil changes recently, I used Mobil 1 LS - no issues as far as I can tell.
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Melting Slicks
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From: West Virginia
For the sake of completeness, this is what the Service Manual for the C5 originally said:
Rear axle lubricant GM P/N 12345977 or equivalent (1.6 L, 1.7 Qt)
Limited slip additive GM P/N 1052358 or equivalemt approx. 100ml or 3.4 ozs.
As I posted earlier, LS lubes were not available back then, so you had to use the additive - these days an LS 75/90 will do the job..
Rear axle lubricant GM P/N 12345977 or equivalent (1.6 L, 1.7 Qt)
Limited slip additive GM P/N 1052358 or equivalemt approx. 100ml or 3.4 ozs.
As I posted earlier, LS lubes were not available back then, so you had to use the additive - these days an LS 75/90 will do the job..
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12345977 was old non synthetic fluid which was officially replaced by 89021677(89021678cnd) which is synthetic.
I was not told from GM that the LS series was the new part for the c5. so this is why I didn't use it.
I am sure if it was approved to be c5 ok it would be the new part number on the c5 parts catalog.
if you can contact gm or ac delco and see what they say that would be handy info to share.
I was not told from GM that the LS series was the new part for the c5. so this is why I didn't use it.
I am sure if it was approved to be c5 ok it would be the new part number on the c5 parts catalog.
if you can contact gm or ac delco and see what they say that would be handy info to share.
Last edited by 1999C5JSS; Mar 10, 2015 at 10:45 AM.
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just so we are clear you are saying you have the proof from GM parts catalog etc for a c5 generation cars listing that it is the fluid for us to use?
reason why I ask is because GM told me my listed part number is correct.
I made this posting on here to help others in future get the facts.
please confirm or share you findings stating gm calling your part number as new fluid to use
thanks for all the help guys.
please lets keep this posting talking about GM fluids not amsoil etc
