ID'ing gear ratio

[rce2win]

I just pulled the stock rear from my IROC and i was wondering if there's an easy way to ID the gear ratio. I have the rear end at home, the car is out in Chelsea. Do the castings on the axle mean anything? Worse comes to worse i can always just put it up on a couple jack stands and give it the spin-check. Thanks...

[sman]

Well, I know on the 2nd gens, that there was a number cast or stamped into the tube or center section on the passenger side facing the front of the car, than had a letter and a number or 2 letters and a number, or something similar. You can figure it out using that if your car has that marking, otherwise you will have to get the option code, the white sticker on the driver door, or glovebox. You want the one that starts with GU then a number ie GU4, GU8.

Post up what you find and we'll figure it out.

EDIT: beat me to it, that should be correct unless the car was ordered with something different.

[Darren]

www.thirdgen.org is a great resource, your car is a 1988 Iroc-z, 350/auto? They have all the specs over there listed I think thats all you need to look for. I will check too and see what I find.

I think this is the page: http://www.thirdgen.org/1988-chevy-camaro

[rce2win]

www.thirdgen.org is a great resource, your car is a 1988 Iroc-z, 350/auto? They have all the specs over there listed I think thats all you need to look for. I will check too and see what I find.

Oh, i'm on that site daily. The car is an '88 IROC w/ the 305 and a T5 manual trans. LMK if you track it down before i do.
Thanks for the help...

[Darren]

Oh, i'm on that site daily. The car is an '88 IROC w/ the 305 and a T5 manual trans. LMK if you track it down before i do.
Thanks for the help...

If its TBI then its 3.08 gear it its TPI with the G92 RPO code then it has 3.45. If its not then its just 3:08.

[ThreeHonks]

number of teeth on ring gear divided by number of teeth on pinon gear.

[rce2win]

If its TBI then its 3.08 gear it its TPI with the G92 RPO code then it has 3.45. If its not then its just 3:08.

The car was a TPI. This would be much easier if i had direct access to the car. It does have the monster hollow front sway bar and aluminum drive shaft, not sure if that says anything as to whether it's G92 or not. Tell you what, today when i get home, i'll put it up on jack stands and spin it, count the turns. Should be pretty obvious to tell the difference between 3:08 and 3:45.

Will post when i get done checking it out.

[ezcruisn71]

There is a two letter code stamped on the front passenger side of the axle tube or on an identification tag attached to the carrier cover. It identifies that axle code ratio and if the axle is equipped with the Safe-T-Track option.

Code -- Ratio
6HE -- 2.73
6HP -- 2.73
6HT -- 2.73
4ET -- 2.77
6HB -- 3.08
6HF -- 3.08
6HK -- 3.08
6HQ -- 3.23
4EU -- 3.27
8EU -- 3.27
6HL -- 3.42
4EW -- 3.45
8EW -- 3.45
7EW -- 3.45

[Gottork]

this kinda on topic but off..

My brother picked a 85 F150 4x4 how can I find out what front gear ratio and rear gear ratio it has?

We think the rear was changed out .. DO I have to remove the pigs and count teeth or is there another way?

[sman]

Jack it up in the air, turn the pinion see how many turns it takes to turn the wheels 1 time and thats your gear ratio. If it takes about 4 turns then you probably have 4.10's.

[ezcruisn71]

this kinda on topic but off..

My brother picked a 85 F150 4x4 how can I find out what front gear ratio and rear gear ratio it has?

We think the rear was changed out .. DO I have to remove the pigs and count teeth or is there another way?

If my memory is correct back from my dealership days it should have an ID tag right on the Rear Axle Housing. They used a 3.50 and a 4.11 that year in the F-150.

[rce2win]

I'm going to try to locate that stamp today when i get home. Hopefully that area's still readable.

There is a two letter code stamped on the front passenger side of the axle tube or on an identification tag attached to the carrier cover. It identifies that axle code ratio and if the axle is equipped with the Safe-T-Track option.

Code -- Ratio
6HE -- 2.73
6HP -- 2.73
6HT -- 2.73
4ET -- 2.77
6HB -- 3.08
6HF -- 3.08
6HK -- 3.08
6HQ -- 3.23
4EU -- 3.27
8EU -- 3.27
6HL -- 3.42
4EW -- 3.45
8EW -- 3.45
7EW -- 3.45

[Gottork]

Jack it up in the air, turn the pinion see how many turns it takes to turn the wheels 1 time and thats your gear ratio. If it takes about 4 turns then you probably have 4.10's.

ok gonna do that so we know, is that the same for the front too?

[rce2win]

Looks like i have a 3:08 posi rear. Thanks for the help all.