1950 GMC 3100 rear end advise needed

[anythingonwhlz]

I just got a 1950 GMC 1/2t SB 3100 w/ sometype of a 6lug drum rear end thats already an open drive line. Its works great but I would like to switch to a 5 lug wheel pattern,so what rear end would bolt right up to my new 1950 GMC w/ minimal if any modifications. I would like to remain drums all the way around. And also can I just switch to 54 drums in order to change the front to a 5 lug wheel pattern and will that be a direct swap in the front?
Thanks for any advise given to me in advance

[Steve@OldSub.com]

Originally Posted by anythingonwhlz

I just got a 1950 GMC 1/2t SB 3100

That would be a very unusual truck. 3100 is a Chevy model designation. A GMC 1/2-ton would be a 100.

Originally Posted by anythingonwhlz

I would like to switch to a 5 lug wheel pattern,so what rear end would bolt right up to my new 1950 GMC w/ minimal if any modifications.

Most people swap the rear from a Camaro or a Chevelle or maybe an S-10 4x4. Others will suggest a Ford 9 inch or 8.8 but those will not match the proposed lug pattern on the front.

If there is a 5-lug rear that will simply fit without modifying the mounting pads I don't know which one it is.

Originally Posted by anythingonwhlz

I would like to remain drums all the way around.

Do you have the hubs, drums and backing plates to convert the front? If not it might be cheaper and certainly easier to find parts to convert to disk on the front.

Originally Posted by anythingonwhlz

And also can I just switch to 54 drums in order to change the front to a 5 lug wheel pattern and will that be a direct swap in the front?

You need to switch the bearings and the backing plates too, and may need to redrill the holes in the backing plates. Its been many years since I last did this swap and don't remember the details.

I prefer a disk brake conversion because I believe it results in a safer vehicle using easier to maintain parts and if you shop carefully does not cost a lot to do.

[mobileortho]

Here's a copy of an article that was posted here a few weeks ago. I'm not aware of any direct bolt on replacements for the front that won't require the use of an adapter, but there are a ton of aftermarket kits available for the AD.

[anythingonwhlz]

Steve
Thanks for the info. Then it must be a GMC 100 I thought it was a 3100 series. I really dont want to have to do alot of mods to swap the rear end. I was hoping there is a simply drop in and bolt up 5 lug rear end. As for the front didnt realize alot also needed to be done. I thoght I could just slip on a 5 lug drum,am I wrong?
Thanks again

[Steve@OldSub.com]

Originally Posted by anythingonwhlz

I really dont want to have to do alot of mods to swap the rear end. I was hoping there is a simply drop in and bolt up 5 lug rear end.

Unfortunately there is no drop in and bolt up 5-lug option. The link Robert posted shows a number of approaches others have taken. And I didn't see anything there that surprised me in any way.

The stock rear was about 62 inches wide wheel mounting surface to wheel mounting surface. If you get much narrower than that the tires will rub the bed, much wider and they will stick out of the fenders. So you want to find a rear that will put your wheels and tires inside the wheel well with enough clearance both inside and outside.

Originally Posted by anythingonwhlz

I thoght I could just slip on a 5 lug drum,am I wrong?

Well you said '54 and I limited my thinking to '54 car brakes. The '51 to '54 Car has Bendix type brakes which are different than the Huck brakes a '50 has.

I've never swapped Huck brakes but its possible that 5-lug Huck drums and hubs would be almost that easy. Those would be '49 and '50 Chevy car brakes.

I've not tried this particular swap but that could be easy to do without the backing plates though you may still need to match the bearing sizes.

I last did this type of swap in the middle 70's and I'm a little fuzzy on some of the details especially the bearings part... If I'm wrong I'm sure someone will come along and correct me.

Like I said before, I prefer the disk conversions for the front these days. I can't imagine doing all that work and still having drum brakes. Especially Huck drum brakes...