47-55.1 1954 3800 Rear axle

[66gmcsuburban]

Hello All Working on a 1954 3800 .The truck has 14" rear brakes .Would i be able to put smaller brake backing plates on the rear end The 12x2 .I do not want to use the 17" wheels and the 14" drums have been cut too many times . Thanks

[mr48chev]

That's a new one on me. I am guessing that it is a single rear wheel truck ? 54 3600 3/4 ton had 12x2 rear brakes. If you can swap drums and backing plates and not the complete rear axle assembly drum to drum I am not sure.

[whitedog76]

I'm about 99% sure you can swap with a 3600 truck. Are you doing the front too? I believe it has the larger drums also.

If you want some dimensions on the 3600 drum setup, I can dig my tape measure out and do some checking on my 54.

[66gmcsuburban]

Thanks .I will start taking apart this weekend

[mr48chev]

I'll say one thing, that is the poster truck for "Patina" this is what genuine patina looks like on an AD truck not rust and decay. Some scrubbing and buffing and polishing and that old girl will still have a nice but gently worn shine and not show abuse or neglect.

I searched but can't find a definitive answer on swapping the drums and backing plates I am like Whitedog76 I think it is a direct swap but you will have to be into it that far before knowing.

[whitedog76]

I bought a parts truck that was almost identical to that one. Well, with the exception of all the rust, caved in roof, oh and about 200 lbs if coon crap. LOL!!!! Any, I have s set of Mariner blue fenders and a grey grill in the attic with a bashed nose piece.

[Bimus]

Are the front and rear brakes on your 54 Huck or Bendix ?

in the picture this out of a 54 3/4 ton with Bendix

[66gmcsuburban]

I found a replacement axle out of a 1955.2 3600

[mr48chev]

54 should have had Bendix on 3800 Rock Auto only shows Bendix wheel cylinders on 54.

[mr48chev]

That 55.2 rear should work pretty good for you if the gears are right and it is in decent shape. It might actually have closer to decent road gears than the 3800 rear axle.

[whitedog76]

The 52 and newer trucks were all bendix brakes. A 3600 should have 4.57 rear gears vs. 5.13 for 3800. Slide axle out, swap center chunk.

On a side note, you can swap a full floating 14 bolt under that old girl also.

[Bimus]

The two 52 one tons I have both have Huck brakes 14 inch in the back and 12 inch in the front with 7.50 17 tires 45 mph is about it .

[66gmcsuburban]

Thanks for the responses

What years is the 14 bolt interchange from

[weim55]

Originally Posted by 66gmcsuburban

Thanks for the responses

What years is the 14 bolt interchange from

I think none, because the axle width in the 14 bolt years are too wide to fit correctly in the fenders on 47-54.

If you are asking about just the brakes swapped from a 14 bolt I believe I have read on the forms here it is doable but I’ve never actually done it myself.

Steve weim55 Colorado

[mr48chev]

I'd say Weim55 is absolutely correct, the 14 bolt rears are 73 and up though that square body style. Different pages say different things on width but the narrowest I can find is 63 and there is no info on what that comes out of. Most seem to be 65 wms to wms. I did find that some of the width is controlled by the hubs and not the actual axle housing width. Still big and heavy for a truck that probably isn't going to do serious hauling or serous work.

[whitedog76]

The HO52 measures in at 62.5" WMS.

The 73-87 Cab&Chassis model is the best fit. They are 1/2 inch wider than the HO52.

The full float SRW model uses the same housing, tube length and axle shafts. The difference is in the hubs and brakes. It's 67" WMS-WMS. You would have to use a set of dually hubs and get creative with the brakes. You can use the HO52 hubs on these, with the appropriate bearings and get an axle that is around 64-65" WMS, but again you have to get creative with the brakes.

I originally had planned on using a SRW axle and the Dually hubs on my 3600. I obtained both. The brake mount flange would've needed to be torched off and moved on the axle. I then figured out that I could use the HO52 hubs and Drums from a van, which seemed to be the ticket. In the mean time, I robbed a rear disc setup off of a 2003 van, I never really made headway with it, but that's an option too.

After a 8.8 axle came available to me, I decided to go a complete different route. I figured there was no need to do such a heavy duty build on the 3600, when I'm never going to use the truck that way. If I had a 3800 truck I would've done the 14 bolt swap and front disc conversion.