Gear ratio numbers
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Joined: Jul 2004
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From: Waynesville,Ohio
Car: 1989 Trans Am
Engine: 350 TPI
Transmission: 700R
Axle/Gears: 9 bolt 2.77
Gear ratio numbers
I read somewhere that the gear ratios are stamped on the driver side axle tube is this true? Can someone post a picture of what they look like cause I cant see mine?
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From: Irmo, SC
Car: 1992 Pontiac GTA
Engine: 305TPI
Transmission: 700R4
Axle/Gears: 10-bolt, 2.73
No, the axle code is stamped on the right-side axle tube, not the ratio. Try brushing away the road grime if you can't spot it.
The first three digits are the actual axle code.
Sorry I don't have a picture, but there's a decent one in the Haynes manual for Firebirds under the Clutch and Driveline chapter.
HTH
The first three digits are the actual axle code.
Sorry I don't have a picture, but there's a decent one in the Haynes manual for Firebirds under the Clutch and Driveline chapter.
HTH
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From: 51°N 114°W, 3500'
Car: 87 IROC L98
Engine: 588 Alcohol BBC
Transmission: Powerglide
Axle/Gears: Ford 9"/31 spline spool/4.86
The axle code is stamped on the front of the passenger side tube near the center section. A wire brush is usually needed to find and read the code. The code can tell you what was originally in the diff but doesn't mean that's what's in the diff. At any time in the car's history the diff gears could have been changed or the diff swapped out from another third gen.
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From: Irmo, SC
Car: 1992 Pontiac GTA
Engine: 305TPI
Transmission: 700R4
Axle/Gears: 10-bolt, 2.73
The changeover from 26 to 28 spline axles happened in the middle of the 1989 production year. I do not think the axle code will help you in determining spline count.
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