Gear ratio?

[Micah.T]

I just bought a 1998 chevy Cheyenne ext can 4x4. I was curious about the gear ratio, there's no sticker to tell me and I've tried the other way, jacking up to see how many times the drive shaft turns to turn the tire once and it's only a little less that 2 times which doesn't seem right. Any one know what I'm doin wrong or can tell me the stock ratio?

[00Silverado4x4]

Does the truck has the stock size tires? If not, that will throw off the true gear ratio count.

[Micah.T]

265/75 r15, I have no clue if that's the stock.

[00Silverado4x4]

I do believe the original tire size was 235/75/R15. I'm trying to open the owners manual to see if that will help if finding the original gear ratio, provided that also hasn't been changed.

[00Silverado4x4]

This is what I have found...

 

https://assets.gm.com/manuals/chevrolet/1998_chevrolet_1500_owners.pdf

 

Pg 4.52 talks about towing vs gear ratios. For the 4x4 the options look like either 3.42 or 3.73. However in the 2wd there is also a 3.08 option. However, based on your information I'm not sure what you have going on in there. You pay have to take the diff cover off and start counting ring and pinion teeth to figure this out.

[Micah.T]

Okay, yeah I have no clue if it's been changed or not, Thank you though. If it Is 3.42 or 3.73 how well do you think it'll do with 33" tires?

[00Silverado4x4]

I'm not a tire to gear ratio expert. Have a look in the wheels and tires forum. There is plenty of good reading on that very topic.

[Micah.T]

Okay, thanks for the help

[nibael]

check the glove box for a sticker with a bunch of three digit codes on it. the rear axle is a G code. GU6=3.42, GT4=3.73.