ZR2 rear?

[Tatt2d51]

I got a stock 51 chevy p/u and was looking to replace the rear and I thought I read in a couple threads about using the ZR2 rear axle for a replacement.
Well I came across one for $300 and am looking for any ones experiences with them. Its off an '02 with 70k miles. It was a 4x4 if that matters. He says its a limited slip with rear disks and he's also got the 5 speed xmission that i could also purchase. I'm thinking about both.

Yah, or nay? On either ?

BTW, I'm currently only planning on running a mild SBC up front.

[britnjc]

I did it and it was the only rear I could use without spacers on an S10 frame. I used the disc on my rear drum set up and just used a disc break pressure reducing valve in line. It works great. if you run wide tires you better check your offset to make sure the tires wont get into the fenders. I had no problems.

[Dirty Doug]

I thought the ZR2 was to wide . What wheels and back spacing are you planning on using? I used the 4X4 rear from a non ZR2 . They are 59.75 w.m. - w.m. and with disc brakes and a posi and 373 gear. The ZR2 is like 4" wider and has a deeper gear ratio. Just my thoughts on it.

[RootBeer 6117]

I put one under mine I don't have the wheels for it yet but by the measurements I have 6" from the wheel mounting surface to the inner lip of the bed and 5 to the outer lip an 8" wide wheel with a 4" back space should fit just fine.
Tuesday we had a ZR5 in the shop for some tire work so I stuck the wheel on my truck to see what it will look like.
The top photo is the old 2wd rear end compared to the ZR2 (one of the these days I am going to figure out how add the caption above each photo).
at this point the bed is just setting on the frame. if you need any more measurements let me know.
Joe

[britnjc]

Originally Posted by Dirty Doug

I thought the ZR2 was to wide . What wheels and back spacing are you planning on using? I used the 4X4 rear from a non ZR2 . They are 59.75 w.m. - w.m. and with disc brakes and a posi and 373 gear. The ZR2 is like 4" wider and has a deeper gear ratio. Just my thoughts on it.

Well like I said I did it and have had two different sets of wheels on my truck no problems. but it you want to run a deep dish rim then you will encounter some problems. I am running a 17 x 8 rim with zero offset no problem.

[Tatt2d51]

I appreciate the replies.

In the above picture, Is it me,or is the center pumpkin of the axle off-center? I've never actually seen a 4x4 ZR2 rear axle so I didnt know if they are off-center or not. If it is off-set i might pass on it just to keep it simpler for this novice.

Again - thanks for the responses.

[britnjc]

not off center. pic is just playing tricks on you. It is a bolt in deal... trust me I did it. I did have to shorten my drive shaft though. I took a measurement and carried my drive shaft to a local shop and about 20 buck later I had a drive shaft to fit. you will also have to go to a chevy dealership and get a u joint that will fit your 2wd driveshaft with the zr2 rear. it is a not hard though. I promise.

[Tatt2d51]

Sweet!
Thanks again, I'll call and see if its still available.

[95 S_Trucker]

fyi, its a locker in the zr2 rear, not a limited slip

[Tatt2d51]

By email he specified

"It is a 3:73 ratio 8.5 ring gear with G80 gm calls it limited slip "

?? Not sure i want a locker...

[RootBeer 6117]

Here is a better shot of the rear axle, the width on the ZR2 and the late 70s-early 80's camaro rear axle are real close. I was able to get this one for $150 from a guy that had rolled his truck.

[95 S_Trucker]

Originally Posted by Tatt2d51

By email he specified

"It is a 3:73 ratio 8.5 ring gear with G80 gm calls it limited slip "

?? Not sure i want a locker...

its a locking diff. the mechanism was manufactured by eaton. its called a governer lock, gov lock for short. they are prone to coming apart under abuse, but should be fine for a cruiser. my 97 has one in it and my 98 had one in it. both still intact.

heres a good short video for it, looks to be training material:

http://www.youtube.com/watch?v=tTGZOJQQBeE&feature...

[Atomsplitter]

$150 for that is a steal where I'm from!
Discs, 8.5" and I remember correctly they're 30 spline axles...sound pretty bullet proof for a cruiser.
My buddy has a pair that are almost exactly the same but they have 3.42 gears in them.
He has been offered $600 for one!

[Chevy51]

Hope,you don't mind,but I thought I would share with you my experience,I had with the rearend swap.I found out that the S10 4wd truck is 60"wide,and will give the right width for the swap,without using spacers. Also you need to consider wheel backspacing,and I found that the 31/2 back spacing is better,according to the size tires you use. I made the mistake of getting an S10 blazer 4wd rearend which is 59''wide. I got it for $50 dollars,and it was posi-trac 373gears,so for that price,I kept it and went with the aluminum billet spacers.1.5",with 41/2" backspace on the wheels,which I already had,or I would have went with,31/2" backspace on new wheels,but to save funds,that is the way I went. Hope I have been of some help.

[Chevy51]

The pictures,are not that great,here is a picture,of me 51,3600Chevy,3/4ton after the swap.

[Tatt2d51]

I thought I read somewhere that the ZR2 rear is 63" vs the AD is 61"
Is this correct?
I guess I got another week to make up my mind or find another alternative. Wont be able to get with the seller til next week. Oh well...

[Dan Bowles]

The ZR2 is the one you want. It is only 4wd and it is wider than a stock 4x4 rear end. Get it for that price! The stock 4x4 rear end needs spacers.

The 5 speed trans won't do you any good, though, unless you want a transfer case, as well!