Rear Locked Need to know if I am an idiot

[Sven]

Hi all,

I am new to the forum, first post!, and I am in trouble of course.

My drive train was making a whining noise. I replaced all drive train fluids and the front wheel hubs. It still made noise then the rear just started grinding. I towed it to S T S out of desperation. They want $3,000 to put a rebuild rear on the truck, axles and differential. I was a bit shocked.

So I basically have to order a rebuilt rear end and do it myself. My issue is that the truck is at S T S. Can I disconnect\remove the drive shaft, put it in 4WD and drive it home (about 8 miles)?

Can anyone recommend a place to get a whole new rear end, I'm in NJ?

My truck is a 2003 ZR5 Crew. I know its the 7 5/8 ring, but I don't know the ratio. Can anyone help me?

Thanks all.

[HenryJ]

If the rear is toast, pulling the shaft is not going to help.

Look for a ZR2 rear axle to replace the one you have. That is the best way to go. There are a few good threads on the bolt in swap.

[Sven]

Hi, thanks for your reply,

Removing the drive shaft is not my permanent fix. I was just wondering if I would hurt anything if I drove it in 4WD with the rear drive shaft removed for about 8 miles? I am going to order a whole rebuilt differential and axles, but I need to get her home to work on it.

sry for the confusion.

[HenryJ]

I wasn't confused. If the rear axle differential , pinion or wheel bearings are damaged, removing the drive from the back is not going to help. It will still have problems rolling. Removing the rear shaft will require fabricating a way to seal the rear of the transfercase so you don't leak fluid. You could give it a shot, but if it is towable, that might be easier. If it is indeed damaged, a trailer may be the best option.

[killian96ss]

It is possible to drive without the rear driveshaft connected (I've seen it done), but you have to put something like a bag with a rubber band over the end of the transmission tailshaft to prevent fluid from escaping and leaving a trail behind you. If the rear end has serious damage inside like broken teeth it is possible that it could lock up so make sure you drive slow on the way home and stop every couple miles to make sure everything looks ok and that your not losing fluid.

$3k is way too much for a rebuilt rear end, especially the weak 7.6"! A good used 8.5" rear end from a ZR2 is a much better option!

Steve

[Sven]

Awesome. I would like to get a ZR2.

I found one:
2000 s10 zr2 8.6" 10 bolt 3.73s and posi with discs

So this will be a bolt in replacement for my 2003 s10 zr5 4x4 with a 7.625 rear with discs? If so I am very excited!

[killian96ss]

I have not personally done this conversion, but as far as I know it is a direct bolt in swap using the factory Crew Cab leaf springs. The ZR2 axle is also a few inches wider than the CC axle which makes the front and rear track about the same.

Steve

[HenryJ]

ZR2 rear axle upgrade

[Sven]

Alright. I bought a ZR2 rear axle from what I am told was a blazer/s-10.

Everything went pretty smooth so far, but I have run into a problem and I need some expert advice.

When I went to reattach the drive shaft, I noticed that the mount on the diff that holds the u joint is different and it doesn't seems to want to fit with my current u-joint.

What is my best course of action here? I can post pics when I get home.

[F9K9]

Pics will help. Do you know what year the donor vehicle was?

[Jongo88]

Awesome. I would like to get a ZR2.

I found one:
2000 s10 zr2 8.6" 10 bolt 3.73s and posi with discs

So this will be a bolt in replacement for my 2003 s10 zr5 4x4 with a 7.625 rear with discs? If so I am very excited!

It looks to be a 2000....

[HenryJ]

...

When I went to reattach the drive shaft, I noticed that the mount on the diff that holds the u joint is different and it doesn't seems to want to fit with my current u-joint.

What is my best course of action here? I can post pics when I get home.

Measure the size difference and get a new u-joint that will convert to that size. Easy find.

[killian96ss]

Is the Crew Cab u-joint too wide or not wide enough or are the bearing caps a different diameter? What problem are you having fitting the CC driveshaft/u-joint to the ZR2 pinion yoke?

Steve

[Sven]

I found that the ujoint I had was a 3r/S44 Saginaw ujoint and the size on the yoke was 13605 (i think , going by memory). I found a conversion ujoint for $33 and installed it. So it seemed like an easy fix, but getting the ujoint out of the Aluminum drive shaft was difficult.

I had to heat the end of it with a propane torch until 'stuff', which I guess an anti-corrosion agent, popped out of the hole on the side of the driveshaft. Once that pressure was gone I could get the ujoint out.

There is no anti corrosion agent on the new ujoint, I covered it liberally with anti seize and installed. Hopefully that does something.

Anyway, I put it all back together and it runs like a champ. Though, in a totally unrelated matter, my radiator cracked ... if its not one thing its the other.

thanks everyone for their help.

[killian96ss]

The factory u joints are held in place by nylon that was injected though those little holes. I'm guessing this was done to speed up manufacturing? The only way to remove the factory u-joint is to melt the nylon out. Replacement u joints are held in with traditional retaining clips. There is no need for anti-seize on u-joints, but it won't hurt it either. If they are greaseable make you lube them once in a while.

Steve