6 sp and diff fluid change. Opinions please.
Thread Starter
Instructor
Joined: Jul 2012
Posts: 175
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From: Strafford, New Hampshire
6 sp and diff fluid change. Opinions please.
So while I have it all torn apart, doing a clutch job in a 97 6 speed. 88k miles. Should I change the tranny and diff fluid? Opinions on what I should use and how much to buy? I am a spirited driver, so she gets a good workout most times I drive it.. TIA
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buy 4qts for the trans and 2qts for the diff and you will likely have a small amount left over from each... I am a fan of amsoil torque drive and severe gear 75/90, been using that in my car since I bought it and never had an issue with the drivetrain... I have never used the diff addidive with the amsoil severe gear and haven't had any noises so I don't think it is needed... I change mine out religiously though, once every year or so regardless of mileage
Melting Slicks
Joined: Jun 2002
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From: Mobile al
And don't overfill the diff, you will create an axle seal leak.
If the car is on a rack or level let the fluid run out of the fill plug until it stops when you fill it. Put the plug in and you're done.
If the car is on a rack or level let the fluid run out of the fill plug until it stops when you fill it. Put the plug in and you're done.
Le Mans Master
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From: OK
buy 4qts for the trans and 2qts for the diff and you will likely have a small amount left over from each... I am a fan of amsoil torque drive and severe gear 75/90, been using that in my car since I bought it and never had an issue with the drivetrain... I have never used the diff addidive with the amsoil severe gear and haven't had any noises so I don't think it is needed... I change mine out religiously though, once every year or so regardless of mileage
Tech Contributor
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From: Anthony TX
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St. Jude Donor '08
Your 97 has paper Synchro blocker rings and synthetic ATF can damage them. NOT RECOMMENDED to use synthetic ATF in your trans.
Either use an OEM Compatible ATF or use the AMSOIL Torque drive trans fluid! They don't make DEXTRON III any more but there are compatible dino stock ATF fluids..
I HIGHLY RECOMMEND the AMSOIL Product!
When you drain and fill, you will only be able to fill to 3.75 qts.
A NEW DRY NM6/NM12 will take 4 qts.
BC
Either use an OEM Compatible ATF or use the AMSOIL Torque drive trans fluid! They don't make DEXTRON III any more but there are compatible dino stock ATF fluids..
I HIGHLY RECOMMEND the AMSOIL Product!
When you drain and fill, you will only be able to fill to 3.75 qts.
A NEW DRY NM6/NM12 will take 4 qts.
BC
Last edited by Bill Curlee; Sep 2, 2016 at 12:09 PM.
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From: San Jose CA
I'm dubious that this is due to thermal expansion, and more likely what appears level to me on jack-stands might not actually be. But if you're doing this in the garage, after you lower the car back onto the ground, there's more than enough space to reach the fill plug. Check the level with the car back on the ground. And if you get a leak, try warming up the fluid and checking the level again.
Melting Slicks
Joined: Jun 2013
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From: West Virginia
They actually do make Dexron III fluids - they are just not allowed to call them that any more, due to GM's control of Dexron as a trademark. My '98 is running Valvoline DexMerc, which is labelled for older GM cars which require Dexron III. Get it from pretty much any autoparts shop - plus Walmart sells it by the gallon jug. Non synthetic, works just fine.
I was surprised just how much difference to smooth shifting a tranny oil change makes. Vowed to do more it regularly in future.
I was surprised just how much difference to smooth shifting a tranny oil change makes. Vowed to do more it regularly in future.
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Le Mans Master
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From: Allentown PA & Elk Twp NJ HPDE Addict
I use the same thing, but if you're not planning on tracking the car I think most brands will be fine regardless of spirited driving or not.
Thread Starter
Instructor
Joined: Jul 2012
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From: Strafford, New Hampshire
I'll go with the good stuff for my baby. So the Amsoil Torque Drive ATF for the 6 speed stick? I guess I have never heard of 6 speed standard oil..
Last edited by cloud 9; Sep 3, 2016 at 07:00 PM.
Intermediate
Joined: Apr 2014
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I used Royal Purple, MAX ATF, it is recommended on their website.
I used Lucas Oil's product for the diff. All synthetic.
Car shifts smoother than before. Lot's of good products, Red Line, Amsoil, etc. All a personal choice. Enjoy.
Thread Starter
Instructor
Joined: Jul 2012
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From: Strafford, New Hampshire
Thank you for all of the replies! So the clutch job went well. I replaced the fluids with the Amsoil products some of you suggested. I installed my c6 shifter, threaded it and put my c5 ball on it. I put a washer in the detent on the transmission. The combination made a world of difference in shifting. I love it. Feels like it should 