Will a ZR2 S10 truck diff/rear end bolt in my Blazer? I have an opportunity to buy a front diff/rear end with 3.73 gears/G80 for cheap. Would be a nice upgrade from my 3.42s/open diff as I will be running 31s shortly.

 

Yes it will. That's what I have under my Blazer. The only real differences between them is the spring perches on the S10 axle won't have the frame bump stop cups. Not a big deal. The front diff is exactly the same, so it's a direct swap.

 

Awesome thanks. Been driving around on 265/70/16 for a few days and the Blazer isn't as slow as I thought it'd be, but the shorter gears should perk it up. Can't wait.

 

With 3.73s and 31s I could spin my tires all day long if I wanted to! We will see how 5.13s and 37s do now lol!!

 

did you end up buying the axle and diff? What did you pay for the combination? I found a zr2 axle and diff for sale, the axle doesn't have brakes on it. Given everything is in normal condition, what's it all worth?

 

I missed the opportunity...now Im kicking myself in the a$$ because I want a G80 for winter. I was going to buy both front and rear diffs off a rolling chassis for $350.

 

While the G80 can be nice in low traction situations you do have to be careful with it on snowy/icy roads. Because one tire will slip first, then the G80 locks it can have a tendancy to kick you sideways when you're accelerating or when the transmission shifts. This can be a concern with any automatic locker. It's not a big deal if you're aware and careful but it is something that's important to know for winter driving in a RWD vehicle.

 

I agree. I've slowly drifted into a curbs at stop lights in my last truck when AWD went out, but those are the conditions I generally have it in 4wd anyway and its easy to correct when the front has pull. I like the extra grip in wet/slushy conditions more so I don't have to worry about spinning slowly through an intersection and turning 4wd on/off. This is my first 4WD and damn if the surface isn't super slick I feel binding and I don't want to wreck anything.

 

just a question
I am new to ZR2s.
I have a 2000 ZR2 that has a very rusty front differential. I am not sure if the case should be replaced. If I choose to replace it for a newer one, can I use a case from a non ZR2 version?
is the front differential the same as base models? I am presuming from what I have read - that there are axle and other chasnges for my ZR2 but it sounds like the cases are the same.
I have to check my codes, but I presume I have 3:73 .gears in this Blazer.
I just picked it up, so I am still exploring the details.
I have to rebuild or replace the transmission... it lost the 3/4 clutch pack... anybody with a transmission out there... let me know... lol
might save me some cash.

 

You would be better served to start a new thread, rather than resurrecting an 8 year old thread. A new thread will ensure that anyone responding can answer your question directly.

That being said, if your front diff is rusty you are one of the lucky few with a cast-iron front diff. Those were only found on very specific model trucks. If it were me, and I were concerned about it, I'd pull the diff and clean it up rather than replacing it. Most likely the rust is just surface rust that could be easily cleaned off and then use rust-converter and an automotive paint to protect it.

You most likely have 3.73 gears if you have a ZR2. If you do decide that you need to replace your front diff, it is interchangeable with 1998+ S-series trucks, as long as it has the same gearing as your truck. Most donor diffs you'll find are the aluminium housing cases, which are fine for almost everyone unless you're looking to do some hardcore off-roading and want to add a front locker.