gm 1/2 ton ifs gear ratio

[jrmbrown93]

Is there anywhere online I can find the gear ratio for a gm 1/2 ton ifs

 

[skylark]

Is there anywhere online I can find the gear ratio for a gm 1/2 ton ifs

There were multiple gear choices offered. Open up the glove box and look at the list of codes. If the glove box is original to the truck and the axles are original to the truck then the codes will show what equipment the truck came with. There will be codes that start with G. Search those codes with RPO (GT4 RPO) after it and you will come up with your axle ratio.

 

[jrmbrown93]

What if its out of the truck and the glove box isn't available

 

[98_k1500]

Cover will have to come off. Ratio is stamped in the ring gear.

 

[Jrgunn5150]

Cover will have to come off. Ratio is stamped in the ring gear.

You can jack it up, trans and tcase in neutral, spin a tire around and count driveshaft turns... Although I would just use tire size, rpm, and GPS speed with a calculator

 

[jrmbrown93]

What about the codes that are stamped in the housing

 

[98_k1500]

They don't mean anything. All 10 Bolt housings (as far as our trucks are concerned) are identical. The only difference is a 4wd truck rear is wider than a 2wd truck rear (longer axle tubes) They have no idea what gear set is going in the axle when the axle housing is made.

 

[Jrgunn5150]

Sometimes they have a tag on the diff cover, but with Chevy's it's pretty rare

 

[98_k1500]

^^^ older ones used to have the tag on one of the pan bolts. Never seen one on one of our trucks tho.

 

[jrmbrown93]

I'm not talking bout the rear diff