1989 MN6 Axle ratio
Thread Starter
Race Director
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From: Overland Park Kansas
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1989 MN6 Axle ratio
According to 1989 Factory specs on Rogers Corvettes G92 is the code for performance axle.
In my owner's manual I think it said 3.07 were base gears -- though it might be lower for base autos. (I don't have the manual handy.) Because I didn't have G92, I thought I had 3.07.
OTOH, I thought I read recently that all 1989 6spds (first year for the MN6) had 3.33 gears. I don't have a Z51.
I can't check by turning wheels (front's on jack stands).
Can someone confirm if I have 3.33 gears....
Thanks
gp
In my owner's manual I think it said 3.07 were base gears -- though it might be lower for base autos. (I don't have the manual handy.) Because I didn't have G92, I thought I had 3.07.
OTOH, I thought I read recently that all 1989 6spds (first year for the MN6) had 3.33 gears. I don't have a Z51.
I can't check by turning wheels (front's on jack stands).
Can someone confirm if I have 3.33 gears....
Thanks
gp
Le Mans Master
Joined: Jun 2006
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From: One day you're a Comet...the next day you're dust... Arkansas
A few early 1989's had 3.54 gears, mine does. Most had 3.33 with the 6 speed. You should have a G__ code that tells you axle ratio. Look in the RPO FAQ's I don't remember them off hand.
Melting Slicks
Joined: Aug 2003
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From: Lakeville MI
From the rpo faq:
G44 - 3.07 Rear Axle Ratio
G87 - ring gear 8.50 inch
G92 - Performance Axle Ratio
GHO - 3.54 axle ratio
GM1 - 2.59 Rear Axle Ratio
GM3 - 3.45 Rear Axle Ratio (8.5 in. Ring Gear)
GT7 - 3.33 rear axle ratio
GU2 - 2.73 Rear Axle Ratio
G44 - 3.07 Rear Axle Ratio
G87 - ring gear 8.50 inch
G92 - Performance Axle Ratio
GHO - 3.54 axle ratio
GM1 - 2.59 Rear Axle Ratio
GM3 - 3.45 Rear Axle Ratio (8.5 in. Ring Gear)
GT7 - 3.33 rear axle ratio
GU2 - 2.73 Rear Axle Ratio
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GHO: 3.54 available on early-89 6 speeds, and as an option on a few later years.
GT7: 3.33 available on Late-89-90 6speeds
GM3: 3.45 standard rear for later 6speeds
GT7: 3.33 available on Late-89-90 6speeds
GM3: 3.45 standard rear for later 6speeds
Thread Starter
Race Director
Joined: Nov 2003
Posts: 12,221
Likes: 446
From: Overland Park Kansas
2020 Corvette of the Year Finalist (appearance mods)
C4 of Year Winner (appearance mods) 2019
Thanks! My codes say GT7 so I have a 3.33....
(That makes me feel better cause I thought I had 3.07 econ/highway gears. The dang thing is about 1500rpm at 70mph on the highway in 6th. Now I know it's really the 6th gearing).
gp
(That makes me feel better cause I thought I had 3.07 econ/highway gears. The dang thing is about 1500rpm at 70mph on the highway in 6th. Now I know it's really the 6th gearing).
gp
