differential leak, dextron 3 vs 6
#1
02-06-2009, 08:29 PM
differential leak, dextron 3 vs 6
hi guys
noticing a steady leak from rear diff on 2000 6 speed, only 26,000 miles sunday driver.The oil is dripping to the low point of the diff, where the gasket seal is but I dont believe its the gaskets, rather than the drain bolt itself, which is up higher a bit.
rumor says these have a "foaming" issue and leak is not from typical gasket seal?
So was planning to drain diff anyway after 9 years and noticed all auto parts stores have replace the dextron 3 as originally specified with newer ATF #6.
I am hoping that maybe the drain bolt is culprit despite having tightened it , so thats why the fluid change to replenish any lost fluid and check the threads on drain bolt.
3 questions:
1)is ATF # 6 correct fluid for differential
2)do I need the additive friction modifier for the "limited slip" to function properly?
3)is there opinion as to general cause of diff leaks for our vehicle?
noticing a steady leak from rear diff on 2000 6 speed, only 26,000 miles sunday driver.The oil is dripping to the low point of the diff, where the gasket seal is but I dont believe its the gaskets, rather than the drain bolt itself, which is up higher a bit.
rumor says these have a "foaming" issue and leak is not from typical gasket seal?
So was planning to drain diff anyway after 9 years and noticed all auto parts stores have replace the dextron 3 as originally specified with newer ATF #6.
I am hoping that maybe the drain bolt is culprit despite having tightened it , so thats why the fluid change to replenish any lost fluid and check the threads on drain bolt.
3 questions:
1)is ATF # 6 correct fluid for differential
2)do I need the additive friction modifier for the "limited slip" to function properly?
3)is there opinion as to general cause of diff leaks for our vehicle?
#2
02-07-2009, 10:57 AM
From your Owner's Manual:
ATF is not for the differential. Its for the manual 6spd. Dexron III is no longer produced/licensed, and Dexron VI is not for the MN6. Per GM use PN 88861800
If you don't have an Owner's Manual, here's one in .pdf that you can download.
http://www.corvettemechanic.com/foru...r-manuals.html
What to Use
To add lubricant when the level is low, use SAE 75W-90
Synthetic Gear Lubricant (GM Part No. 12378261) or
equivalent meeting GM Specification 9986115. To
completely refill after draining, add 4 ounces (118 ml)
of Limited-Slip Differential Lubricant Additive (GM
Part No. 1052358) or equivalent. Then fill to the bottom
of the filler plug hole with the Synthetic Gear Lubricant.
To add lubricant when the level is low, use SAE 75W-90
Synthetic Gear Lubricant (GM Part No. 12378261) or
equivalent meeting GM Specification 9986115. To
completely refill after draining, add 4 ounces (118 ml)
of Limited-Slip Differential Lubricant Additive (GM
Part No. 1052358) or equivalent. Then fill to the bottom
of the filler plug hole with the Synthetic Gear Lubricant.
If you don't have an Owner's Manual, here's one in .pdf that you can download.
http://www.corvettemechanic.com/foru...r-manuals.html
Last edited by El Zappo; 02-07-2009 at 11:01 AM.
#3
02-07-2009, 11:46 AM
Hey thanks for reply!
double thanks, as if i only went out to car and checked owners manual , most of my dumb *** questions were right in front of my face! Wow, they provide a lot of info in this manual, more than most Ive seen.
Ok for those too lazy to read their manual:
rear axel needs synthetic gear oil 75-90 WT, local auto stores have mobil 1: 75-90wt.
and yes u need 4 oz of additive per manual! total capacity 1.69 Qt
anyone have experience with small leaks? it spots overnight and I leave cardboard as my own corvette litter box.
mn6 trany lists dextron 3, but also says no need to change it? my c5 is 9 years old with 26 k miles. should i do it anyway? do I use dex 6 as current replacement to dex 3?
thanks to all who reply, even to insult me for being a lazy ***
double thanks, as if i only went out to car and checked owners manual , most of my dumb *** questions were right in front of my face! Wow, they provide a lot of info in this manual, more than most Ive seen.
Ok for those too lazy to read their manual:
rear axel needs synthetic gear oil 75-90 WT, local auto stores have mobil 1: 75-90wt.
and yes u need 4 oz of additive per manual! total capacity 1.69 Qt
anyone have experience with small leaks? it spots overnight and I leave cardboard as my own corvette litter box.
mn6 trany lists dextron 3, but also says no need to change it? my c5 is 9 years old with 26 k miles. should i do it anyway? do I use dex 6 as current replacement to dex 3?
thanks to all who reply, even to insult me for being a lazy ***
#4
02-07-2009, 12:50 PM
I also have a 2000 MN6. I bought it new, now have 51k miles on it and have not changed the fluid. I have zero issues with the 6spd.
Our '97-'00 6spd have "paper(cellulose) blocker rings" in them and I understand that Dexron VI, which is a full-synthetic fluid, is not good for these rings. Dexron III was a synthetic blend, but is no longer made. Dexron is a GM requirement and is licensed by GM.
GM says not to use Dexron VI in these manual transmisions, but to use the fluid I listed above. I've read that Amsoil ATD is ok.
Our '97-'00 6spd have "paper(cellulose) blocker rings" in them and I understand that Dexron VI, which is a full-synthetic fluid, is not good for these rings. Dexron III was a synthetic blend, but is no longer made. Dexron is a GM requirement and is licensed by GM.
GM says not to use Dexron VI in these manual transmisions, but to use the fluid I listed above. I've read that Amsoil ATD is ok.
#5
02-07-2009, 01:23 PM
So its ok to leave nearly 10 year old oil in manual trans without service? yes, the manual says no need to change. just feels weird to not ever change it?
I did see dextron 6 by castrol, described as a semi-synthetic blend at local parts store, with a "good for GM vehicles " label.
So maybe that will work, if full synthetic is not ok, but not really an issue if no need to change it!
Thanks again for reply.
final post,
Any experiences with rear axel slow leaking?
I did see dextron 6 by castrol, described as a semi-synthetic blend at local parts store, with a "good for GM vehicles " label.
So maybe that will work, if full synthetic is not ok, but not really an issue if no need to change it!
Thanks again for reply.
final post,
Any experiences with rear axel slow leaking?
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DrJ
Corvette C5 Forum
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03-01-2009 05:03 PM
7590, atf, c5, corvette, dextron, differential, equivalents, fluid, gm, leak, lieu, ls, pn88861800, synthetic, wt
