The Stovebolt Site Forums The Parking Lot Tons 'o Fun difference between 1/2 ton to 1 ton suspension

So I am still getting parts together for my 3800... but I am trying to figure out the major differences between all of them. I know the 1 ton has a bigger frame, so a rear cross-member wouldn't work.. but widths sound like they are the same...

I want to update the brakes and want to stay stockish.. but what have you guys changed your rear ends too? I can't decide to stay somewhat stock and swap in a 4.10 or try to get something down to a 3.43 given the lovely price of fuel! Obviously if I swap in I would like to take the brakes with it! We have lots of hills and bad drivers here.. so good stopping power would be nice!

Thoughts? One last question is what you guys have done to the steering to keep it straight on the roads.. the truck has a tendency to veer off the road at 35... but I have heard that might be brake bind...

Your steering issues can probably be solved with new kingpins, tierod and draglink ends, and adjusting and or rebuilding the steering gear box.

For a rear axle and brake swap with lots of gear choices I'd use a GM 14 bolt from a cab and chassis truck.
https://www.stovebolt.com/ubbthreads/ubbthreads.php?ubb=showflat&Number=599879#Post599879

Grigg

Another source of wander is worn out front leaf spring bushings. Worn spring eye bushings will cause the springs to move forward and backward slightly, but just enough to move the front axle, causing wander. I speak for personal experience.

You didn't say what year.. but many of the brake parts are available though depending on the year they may be scarce. One tons have bigger brakes than their little brothers making the somewhat unique.

Ditto what the other guys said

Mine is a 1949, so of course I have the older braking system.

I guess I am just worried about all of the hills that are here and making sure that it will brake properly. I also wouldn't mind some power steering, but I think I might look into the column power steering assist that I have seen.

Has anyone done a power steering upgrade?

I put PS on mine, but honestly if you put new kingpins and bushings in your original axle and run a reasonable tire pressure they steer OK, everything needs to be in good shape.

Grigg

My 51 1 Ton steers very nicely and is easy to stop. If I were starting out, I would first check to see if your drums are OK or if you need replacements. The drums are very hard to get hold of.

If I were to make a change, it would be to put an adjustable proportioning valve on the rear system. The rear brakes are larger and without a load they will lock up before the front ones.

I wouldn't go swapping brakes. If everything is working right these old trucks will stop pretty good. Between the gears and the stock brakes, my '49 3800 drw stops on a dime.

Another question along the same lines.... are the rear of our frames different from the 1/2 tons? Are the frames the same size with the same arches? I am just looking at boxing my frame and I am trying to figure out if I can use heidts 4-link rear system in my truck. The rear crossmember bolts inbetween the frame on both the top and the bottom... so I am hoping that ours is just long in the middle with different type taper at the front end.

Thanks!!

Frame is about 16" narrower, no arches in rear frame, totally different. A rear from a 3/4 ton 60's van should fit perfectly and be a bolt in affair, ride softer, better ratio. Not sure specifically what years.

i have plenty of hill here and i have no issues with mine. the biggest difference ive seen is it a lot bumpier if you dont have shocks.

I am guessing you mean 16 inches shorter? I am thinking more even about the size of the frame rails.... it is more about changing the rear suspension then the axle at the moment... I want to go to a 5 bar kit if I can as it will be a daily driver and it would be nice to not have it jumping around =) I am going with IFS so... something that would match up would be great!

Nope. The rails are actually 16" closer together. The springs hang on the outside of the frame. The 3804 Pickup frame has extensions for the box though.

ontheverge
I'm in the same spot as you right now. I have bought a 1/2 ton axle ($100.00 and the guy can get more of 'em) stripped it of it's bendex brakes. Am about to slide it under my '48 1 ton to line up the spring U bolt holes so I can elongate the holes 3/16 each to fit the '48's U bolts. Then comes the power disc conversion kit ($700).
For the rear I bought ($150 Craigs list) a 12 bolt out of a HEAVY HALF '78-'79. The good points about this rearend are; 1. the spring perches are about right where they need to be no welding required. 2. gear ratio is 3.73. 3. the brake shoes are 40% bigger 4. GVW on the heavy half was 6000 lbs truck only weighed in at about 4000 lbs almost the same as ours weight wise but nowhere near as much as ours could realistically haul.
By doing both changes I think I will drop almost 100 lbs front unsprung and 200 ? rear.
Points of concern are 8 lug to 6 lug, I like the HD looks of the 8 lug but now have more wheel choises, and losing my full 1 ton rating but I don't plan on using the '48 to haul.
As I move through this I will try to keep pictures posted.
If this works as planned I will chuck the hucks! thanks Jim D

They say the one ton frames from 67-72 of the chevy&gmc trucks are a inch and half taller than 1/2 and 3/4 ton im going to make sure about that

Some GM 1 tons, as well as Fords, Toyota's have a rear brake proportioning valve hooked to a lever on the rear to sense spring deflection, thus loads.

So I am going to bring this back from the dead with a question.... I have seen a few guys that have used the 1980ish front suspension out of a Chevy with only a slight narrowing of the crossmember... but they have an issue with the arms being a bit too low.... so as the 3600's are close to our frame dimensions but ours are higher (correct me if I am wrong) could I box and notch the frame in that area to raise it some?

Thoughts?

On my 41 1 ton I compared parts list numbers and determined that the front assemblies were the same so I was able to use a 1946 1/2 to disc brake kit that bolted right up.

I had a new rear end narrowed to math the width of the old one with wider brake shoes.

The result is that it cruises at 70mph @ 2000 rpm and then stops on a dime and give me 9 cent change. I could not be happier with it.

The 41's are quite different then ours unfortunately. For the front rails are they wider then the 1/2 tons? I was speaking with someone saying that ours would be in comparison which would make this swap impossible as already the track width is wider on this swap then the 1/2 tons... so if I had to have a wider crossmember that would only make it a bigger problem....