97 Tahoe Gear Ratio??

[t2timmy]

Hey all,
New to this forum. I own a 1997 Tahoe 2 door LT 5.7. I bought the truck last April with 165 K. It now has 175K. Basically it's stock aside from a chrome grill and blacout and clear blinkers.

How can I find out if it has the 3.42 gear ratio or 3.73?? It has a tow hitch on it but I'm not sure if it's stock. I can't seem to find it stamped on the axle around the diff/pumkin area.

The reason I need to know is I accidentally blew the old one up standing on it from a dead stop. Woopsies. Blew the spider gears and carrier to peaces and out the back of the diff cover.

Thanks All,
Tim

 

[Rollin Thunder]

if you want you can put 3.73's whether you had 3.42 or not, or if you really want some grunt, put 4.10's in. :yesnod:

 

[t2timmy]

I agree. But since I'm on a tight budget, I need to find a swap in axle quickly for this rig with the same ger ratio as the front. I can't spin the shaft and count the revolutions because the rear end is blown up.

 

[Rollin Thunder]

im not sure if they are the same on the 99 and back (gmt 400's) but for my 06 i look in the glove box and see which code i have in there

here they are, these are all possable ratios, one of them is in your glove box, and that is the one you have. :thumbsup:

GT4 - 3.73
GT5 - 4.10
GU4 - 3.08
GU6 - 3.42

 

[t2timmy]

Really?? I'm going to have to open up the glove box and take a look. I take it it's on a sticker?? Never heard of that one. But I'll check.

I know dealers can sometime get it from the VIN. I tried on the internet to find a site that gives you all the info on the vehicle but could not find one for free. My last resort is to pull the ring and pinion gears when I drop the axle and count the teeth and divide the ring by the pinion count.

Thanks bud!

 

[Old Goat]

My 2005 had a GU5 code=3.23
Use this site to decode.

http://mylsx.com/m_rpo.php

Maybe it's somewhere else on that year model. Door frame??

 

[t2timmy]

I'll try that too as a double check. Thanks for all your help.

I'm pretty sure I just found out the ratio (3.73) using the VIN. I had my buddy call his buddy who's a mechanic, who gave me a number of some guy Mark at some parts department (Dealership??) and he checked the last 8 digits of the VIN and found that it came with 3.73.

- NOW - Anyone have a rear axle for a 1500 series with 3.73, in the CT area??

Don't think a 2500 rear would fit cause of the 8 lug bolt pattern.

 

[madspeed]

wow, a buddy of a buddys buddys dealer

 

[41racing]

Most gm 1/2 tons have 373's. Their pretty easy to find at junkyards. Anything from 88 and up should work.

 

[t2timmy]

yes, madspeed.
A buddy who has a buddy who is a mechanic and has a buddy who can read VIN codes. It's a good thing. :smilielol:

I hear ya about the abundance of 10 bolt GM rears. I just don't want to get anything too old and I blow it up again. I also want it for FREE..

I'm not in a rush to fix it as I have sweet Jeep Wrangler (my pride and joy) to drive around in for now.

Thanks all again.

 

[Dianne Skinner]

When you open that glove compartment, you need to do a tab move and roll the glove compartment door all the way past full normal open to get a really good view of the RPO label. Be sure to empty it first, or you will empty it while looking for the RPOs! Old Goat has given you a _great_ pic of one. He is good with a camera, 'cause it is hard to get that good of a shot! If you need the full listing of RPOs, let me know and I'll link you to it or send it to you. You have gotten some good advise on this posting. These guys are sharp. Good luck.

 

[madspeed]

yes, madspeed.
A buddy who has a buddy who is a mechanic and has a buddy who can read VIN codes. It's a good thing. :smilielol:

I hear ya about the abundance of 10 bolt GM rears. I just don't want to get anything too old and I blow it up again. I also want it for FREE..

I'm not in a rush to fix it as I have sweet Jeep Wrangler (my pride and joy) to drive around in for now.

Thanks all again.

Just sold my sweet wrangler !!