9-bolt fluid?
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Joined: Sep 2002
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From: Dallas/Fort-Worth
Car: 1988 Camaro IROC-Z
Engine: 350 TPI (L98)
Transmission: T56
Axle/Gears: 9-bolt 3.45
9-bolt fluid?
I need to change the fluid in my 9-bolt.
What type of fluid should I use, car has 135k. Also, do I need to get that GM additive, I heard that I did not for a 9-bolt.
What type of fluid should I use, car has 135k. Also, do I need to get that GM additive, I heard that I did not for a 9-bolt.
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Joined: Aug 2001
Posts: 814
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From: San Jose, CA, USA
Car: 88 IROC-Z - original owner!
Engine: LB9 with K&Ns, MSD, Foil, Taylor
Transmission: WC T-5
Axle/Gears: BW 9-bolt, 3.45 posi
I just refilled my posi 9-bolt. If you want to spend the money and go with a synthetic oil, the Redline and Royal Purple oils already have the posi additive in them.
If you want to go cheap, just get a good 80-90 or 75-90 GL5 rated gear oil, and some posi additive.
What I did was I mixed one quart of 75-90 Redline with one quart of 75-90 Royal Purple synthetics, and used no extra posi additive. Works fine, no posi noises or jerking when I go around corners, so clearly the built-in stuff works. The synthetics will last longer, lets you go longer between changes.
If you want to go cheap, just get a good 80-90 or 75-90 GL5 rated gear oil, and some posi additive.
What I did was I mixed one quart of 75-90 Redline with one quart of 75-90 Royal Purple synthetics, and used no extra posi additive. Works fine, no posi noises or jerking when I go around corners, so clearly the built-in stuff works. The synthetics will last longer, lets you go longer between changes.
Member
Joined: Feb 2004
Posts: 225
Likes: 1
From: pa
Car: 88 irocz
Engine: b2l 350
Transmission: corvette 4+3
Read your owners manual before replacing the fluid in your 9 bolt or check out my replies in this thead. 9 BOLT GM # s GM does not recommend using any additives in the 9 bolts.
Last edited by 884+3; Jul 23, 2004 at 11:29 AM.
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Joined: Oct 2000
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the 9 bolts require a special additive which GM does NOT carry anymore. the part # has NOT been superseded, just discontinued. check out your owners manual !!
I just use regular gear oil suitable for limited slip useage, and NO additive. works fine...
THe additive is for the clutch type rears, not the cone type aussi's.
I just use regular gear oil suitable for limited slip useage, and NO additive. works fine...
THe additive is for the clutch type rears, not the cone type aussi's.
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Joined: Aug 1999
Posts: 492
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From: Aurora, ON, Canada
Car: 1989 Iroc-Z
Engine: 5.7L TPI
Transmission: 4 Spd Auto
Yes add it. I bought some redline oil that already has friction modifiers in it. The oil costs a bit of money, but for the amount of times it gets changed I figured why not.
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Joined: Oct 2003
Posts: 218
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Engine: L98 5.7
i have a bottle of gm additive, tomarrow, im going to open up my 9 bolt, clean it all up, replace the oil with 80-90. If it sounds worse then now, then ill add the bottle of additive. if it sounds better, then i wont. (my rear makes some noise at speed)
the additive was like 2 dollars or something, im just going to try both ways.
the additive was like 2 dollars or something, im just going to try both ways.
Senior Member
Joined: May 2003
Posts: 804
Likes: 1
From: Thornton, CO
Car: 1987 GTA 350
Engine: L98
Transmission: 700R4/2400 stall
Axle/Gears: B/W 3:27 posi disc
I run Royal Purple in my 9bolts and it work just fine. And for less than $20 you can't beat it plus you pick up some hp.
Laters,
Conrad
Laters,
Conrad
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