1/2 ton 4x4 vs 2wd rear-end

[ElGracho]

Big flick...

Use the housing from the 4x4 guts and all in the 2wd. Swap axles, get new drums. If you didn't build the rear in the 4x4, make sure of the spline count before you buy axles if you are getting new ones. 88-91 10 bolt axles went to 30 spline instead of 28 in all the earlier 10 bolts.

When it comes to axle parts, it sure is hard to be Randy's. Local, everything in stock, and good people to deal with.

I still wish I would have bought that forest service truck when you had it for sale...

[kevinr1970]

Originally Posted by ElGracho

Big flick...

Use the housing from the 4x4 guts and all in the 2wd. Swap axles, get new drums. If you didn't build the rear in the 4x4, make sure of the spline count before you buy axles if you are getting new ones. 88-91 10 bolt axles went to 30 spline instead of 28 in all the earlier 10 bolts.

When it comes to axle parts, it sure is hard to be Randy's. Local, everything in stock, and good people to deal with.

I still wish I would have bought that forest service truck when you had it for sale...

Big flick...???

The 4x4 rear-end actually came out of an '85 GMC 4x4. Would the '88-91 even fit width-wise in the housing; I thought the NBS trucks had a different width?

I am suprised you haven't picked up that deisel SWB I keep seeing on CL...

[ElGracho]

Originally Posted by kevinr1970

Big flick...???

The 4x4 rear-end actually came out of an '85 GMC 4x4. Would the '88-91 even fit width-wise in the housing; I thought the NBS trucks had a different width?

I am suprised you haven't picked up that deisel SWB I keep seeing on CL...

I was trying to summarize. That's what I meant by big flick, big picture etc...

I meant suburban and blazer when I mentioned 88-91. They are really common in the u-pull-it yards now and the last rear I got came from one of those.

I hadn't seen that diesel, I'll have to take a look....

[kevinr1970]

Originally Posted by ElGracho

I was trying to summarize. That's what I meant by big flick, big picture etc...

I meant suburban and blazer when I mentioned 88-91. They are really common in the u-pull-it yards now and the last rear I got came from one of those.

I hadn't seen that diesel, I'll have to take a look....

I hadn't even thought about '88-91 Bl/urbans, good info to know that they are different!

Here is that diesel swb.
Seems a lot of money from my perspective, but I am not really into the diesels.
I will list the ad here as it only has a few days left:
"Rare hard to find 85 K10 with 6.2 diesel. Truck runs and drives well. 119K New Automatic transmission with overdrive. Over 20 MPG! Truck is not perfect does have a dent in the bed and a little rust in the passenger rocker panel. 360-xxx-xxxx"

[kevinr1970]

I had a chance to get some stuff done on the trucks this weekend.

I was talking to a friend of mine and he said to make sure that the backing plates were the same diameter.
While doing that I noticed that althought they are roughly the same diameter, they are shaped different.
The 2wd (5-lug) backing plate is "flat" for lack of a better word while the 4x4 (6-lug) backing plate has an offset to it; they are offset to the inside, towards the diff.

The 4x4 brake shoes are about 2-3/4" wide while the 2wd shoes are about 2" wide.
The drums are about the same width difference also AND this appears to be about the some amount as the offset of the backing plates.

I am pretty sure that there are at least two different size rear brake shoes; 2" light duty and 2-3/4" heavy duty.
We are theorizing that the axles are the same width 2wd vs. 4x4, no matter what brakes are there and that I need to order new drums and shoes for the 2-3/4" brakes and everything should be hunky-doory.

Anyone confirm or refute this?

[ElGracho]

Originally Posted by kevinr1970

...
The 4x4 brake shoes are about 2-3/4" wide while the 2wd shoes are about 2" wide.
The drums are about the same width difference also AND this appears to be about the some amount as the offset of the backing plates.

I am pretty sure that there are at least two different size rear brake shoes; 2" light duty and 2-3/4" heavy duty.
We are theorizing that the axles are the same width 2wd vs. 4x4, no matter what brakes are there and that I need to order new drums and shoes for the 2-3/4" brakes and everything should be hunky-doory.

Anyone confirm or refute this?

You guys are right. Both housings are the same width the parts in either housing would fit the other housing.

You can swap axles and drums to make a 2wd into a 4wd and vice versa. The 4 wheel drives all had the big (2 3/4" wide) brakes while the 2 wheel drive stuff could be had with the 2" or 2 3/4" brakes. I've never had a truck with the small brakes, I think they were mostly on the bare bones type trucks.

You can swap the whole backing plate and drums from the 2wd onto the 4wd housing and use all of your original brake parts OR you can use the big brake backing plates from the 4wd and get some new 5 lug heavy duty drums.

If your brakes worked well in the first place, I'd reuse them, then you don't have to mess with the parking brake cables either. They are a pain...

[kevinr1970]

Originally Posted by ElGracho

You guys are right. Both housings are the same width the parts in either housing would fit the other housing.

You can swap axles and drums to make a 2wd into a 4wd and vice versa. The 4 wheel drives all had the big (2 3/4" wide) brakes while the 2 wheel drive stuff could be had with the 2" or 2 3/4" brakes. I've never had a truck with the small brakes, I think they were mostly on the bare bones type trucks.

You can swap the whole backing plate and drums from the 2wd onto the 4wd housing and use all of your original brake parts OR you can use the big brake backing plates from the 4wd and get some new 5 lug heavy duty drums.

If your brakes worked well in the first place, I'd reuse them, then you don't have to mess with the parking brake cables either. They are a pain...

The 2wd axle was in a bare bones forest service swb, 4.3, 4-speed truck. I don't think they could be had any more bare bones than that!

The brakes shoes were down past the rivets and the drums showed that.
Also, after driving the crew around the block, the wheel cylinder on one side leaked brake fluid badly and it was quite a mess once the drums were pulled off. Smelled pretty good too!

This is in my crew project so I think it would be in my best interest to get the best brakes possible. When we converted the front end to 1/2 ton I bought all new parts for the 1-1/4" rotors.