Any clues here?? I've called St. Charles and they weren't able to decode the VIN. I need to replace the ring and pinion and pretty much everything else back there, but I will need to know the ratio before I order.

And yes, I know the REAL way to find out is to drop the cover and start counting teeth, but I was hoping that someone here would have some knowledge of this upfront.

But not the easiest.

Here's what you do, and easiest done with two people:

Important: Chock the wheels securely, since you're going to be jacking the truck in the rear with the e-brake off and the tranny in neutral.

With some chalk or something, mark a spot on the driveshaft that crosses over to the pinion - you're going to be counting the number of times the driveshaft rotates. Jack up one wheel in the rear. Make sure you've got the other on the ground so it doesn't turn. Start turning the wheel and count the number of rotations you make with it. At the same time, count the number of rotations the driveshaft makes.

For instance, if your rear wheel rotates 20 times while the shaft rotates 41, you've got 4.10 gears.

Wheel: 20 times, shaft 45: 4.56's
Wheel: 20 times, shaft 43: 4.30's

That make sense?

I tried to rely on someone else telling me what kind of ratio I had, and it cost me shipping to get the set of 4.56's sent back and the correct 4.10's sent to me. It's worth your time. HTH,

Mike,

Thanks for the tip. That was the next resort, short of having to count teeth <img src="/forums/images/graemlins/smile.gif" alt="" /> It turns out that the ratio is in the owners manual, and its 4.30:1. I'll double check before I order, but it looks like I've got it figured out.

if you have the Gm 10 bolt you might want to consider going to a dana 44 out of a newer rodeo

I also might want to go for a stroked Chevy 350 and a 6 speed tranny HAHAHA!!! Just kidding, but I know that the Dana unit is a little bit better and longer lasting, but this GM 10 bolt has made it for 145K miles, without a lube change. The cost to rebuild it is apprx. $300 which will include the ring, pinion, and all new bearings. Since it's a 2wd, and more of a family car than anything, the chances of it going offroad into some rough stuff are slim (except for the occassional treks down some of the local dirt roads, but thats another story).

Bottom line is that the diff is close to exploding, and I need to fix this on Friday. Thank goodness for the GM drivetrain in the ZuZu as I was able to order the bearing rebuild kit for $100 from Summit Racing (back to my old hot rod days). Anyone have suggestions on where to find the ring and pinion? It's officially 4.30 in a GM 10 bolt 7.625" carrier.

Randy's Ring and Pinion. The best rearends in the business. <img src="/forums/images/graemlins/butwiggle.gif" alt="" />

I don't get it, though: $300 includes the R+P, but you're asking where to get it? Wouldn't you just rely on the dude setting your gears to source some for you?

If $300 is what you're paying for the whole enchilada, that's a pretty damn good deal. Gears for my axles (with install kits) were running something like $200/axle, plus the $200 to get them set.

Edit by Mod: Link to hot chicks fixed. <img src="/forums/images/graemlins/smile.gif" alt="" />

Sorry that wasn't clear, but that's for parts alone, all labor to my rig is done by myself and my father in law who is a bus mechanic with 25+ years experience. Short of interior work (meaning fabric on the seats, headliners. etc...) all work is performed by yours truly with his watchful eye. I've found the R & P for ~$200 and the rebuild kit for ~$100 so ~$300 total PLUS beer and scotch <img src="/forums/images/graemlins/cheers.gif" alt="" />

Edit: Parts on order from Randy's THANX!!! They were even able to bargin on the price, so I saved 20 more bucks!!! If I blow up my rearend again <img src="/forums/images/graemlins/butwiggle.gif" alt="" />, they will be the ones that I call.

Any R&P from a camaro or s-10 blazer should work as long as its the gear ratio you want. The 10 bolts in the Rodeos is not the same as those in the fullsize chevy trucks.

Dan

Of course I screwed that one up. I'm married. <img src="/forums/images/graemlins/notooth.gif" alt="" />

Fixed it over the weekend. It turns out that the outer pinion bearing had gone out, causing a very loose pinion, and a very clunky rearend. My father in law and I replaced all the bearings and races, but since there was no noticable damage to the R & P we didn't bother with it at all.

It's funny, but sometimes you don't realize how annoying something was until it's gone. How I lived with my rear diff whining like a spoiled child I'll never know. Time to change the sig now<img src="/forums/images/graemlins/notooth.gif" alt="" />