The Stovebolt Site Forums The Parking Lot Big Bolts 1955-1959 chevy & gmc big trucks

Hello all, since i've had the hardest time with my 54 GMC 350 i'm switching to to 55-59 big trucks and leaving my 54 GMC 350 on the back burner.

couple questions:

1) are there any brake/ steering upgrades for these trucks or am i in the same boat as an AD big truck

2) are there any known issues with these big trucks to watch out for? ie: brakes, trans, rear end, suspension, steering, frame problems.

3) anyone know what these trucks are capable of hauling for weight? more specifically how much can they tow not so much gvwr

4) which models will provide me with what im looking for? which would be a truck, trailer, and load totaling 26,000 lbs or less. but it must be able to tow a minimum of 20,000 lbs not including the weight of the truck itself.

as always i appreciate the help!!

1. What upgrades are you looking for? Properly maintained factory brake will still do the job and I've never had a steering issue (all of my truck have manual steering). Power steering was an option.

2. There are no known issues with any of those items.

3. The 6000/60 Series TF trucks have a GVW of 19,000 and a GCW of 32,000, so they fit the bill and the bigger trucks have higher ratings.

4. see #3.

Mike B

i was curious if power steering could be fitted to them without major custom work as the wife will be driving it from time to time. im not too worried about stock brakes but if there are any upgrades available to make them a little better (ie: certain brand of shoes that work better/last longer, master cyl upgrades, power brake upgrade) im picking up a 55 dump not quite sure of the model # yet just wanted to make sure everything is going to be all good. crazy as it may sound im looking to hitch a gooseneck to it in order to make a 1800 mile round trip run to grab a second one of these trucks. i cannot stand the fact auto transport companies want to charge more than the truck is worth too get it home so i plan on doing it myself. but first my 55 is going to be gone through very thoroughly.

im on the east coast but where do you find replacement parts for the brake drums on these trucks? i heard general auto parts stores carry them out west but im not even sure where to look around here in the northeast.

When I rebuilt the entire brake system on my 1957 2 ton I found that shoes are obsolete/no longer available, I think you will have trouble finding new drums but probably find used. I was able to get rebuild kits for the master cylinder and all six wheel cylinders. I am not using the power brake Hydro-Vac at this point due to internal leakage but with manual brakes and loaded with 105 bales of hay I had no brake issues. Rear axle ratio's are going to keep any of this vintage truck either in the slow lane or the slower lane, mine has a single speed rear end with 7.10 :1 ratio - it tops out at 45 MPH against the governor - doe's not care if it's loaded or empty.

i heard on here there was a place you could send out shoes to be relined. ill have to dig for the thread. eventually she will be cummins powered with an OD trans to help her sail comfortably at around 60mph. im curious what is the "governor" on these trucks? is it a block under the gas pedal? i figured a hydroboost kit for a little truck and a custom bracket will solve my power brake issues as well as upgrading to a split master for front/rear easy enough to split the lines. where did you get the wheel cyl rebuild kit from? thanks!!

Mine is the original 283 V8 with a governor that incorporates the ignition distributor and the carbuerator. The distributor has a flyweight/spring actuated valve that allows vacuum to control a carb. mounted diaphram. The shop manual calls for approximatly 4000 RPM as the governed engine speed. I was lucky with the shoes on mine, all have lots of meat - I had to clean and bake one rear shoe to get the oil out of it and it works without grabbing. The rebuild kits are available from Raybestos, you will need the casting number from each wheel cylinder to obtain the correct kit. Don't assume that all of the wheel cylinders will be the same casting #. Wheel bearing seals are also available as are the rubber brake hoses. I would like to add an overdrive auxiliary trans so I don't hold up traffic on the local 55 MPH two-lane but for now I stay on the gravel roads or the blacktop on Sunday mornings to keep away from fast traffic.

so essentially disconnecting that vacuum governor would turn it off? or replacing the distributor and carb with units that do not have those features?

Original distributor could stay in place with a different carb, or the spring rate can be adjusted in the distributor and carbuerator to change the governed speed. The carb. is the tricky part due to the throttle butterfly shaft being linked to the governor and your right foot through a spring, your throttle foot doe's not open the butterlfies, it ALLOWS the governor diaphram to open them. Mine is the Rochester 2 bbl. but the same theory has been applied to the 4 bbl. and I made some repaire's to Holley 4 bbl's. on Chevy 366/427 engines with the same style of set-up.

i appreciate your help! that definitely will be on my list of parts to change. im pretty sure we can get manifolds for a 2bbl carb aftermarket (my 55 dump has an I6) do you know what the stock carb cfm rating is? thanks!!!

A little more info, my truck is rated at 16,000 GVW, that is with 8.00x22.5 tires in front and 9.00x22.5 in the rear. The capacity would be up to 19,000 GVW with optional tires. I was very surprised of the empty weight of 7000 lbs. It is 160 inch wheelbase and cab high 15 ft. wood grain rack. I don't recall seeing any specs on towing capacity for it. Oh, almost forgot, it's a Low Cab Forward.

i know the later years like the spartan 100's had towing capacities. i was figuring somehow these would have a towing capacity as well not just a gvwr for the truck and the cargo in the bed or body. i can imagine they would be able to tow more than what you could put on the bed just like any other truck. mike had said above the 6000 series had something like 30k+ gcw. to be brutally honest the most it would ever be pulling is right around 15k and that would be a trailer with another truck just like it on the back.

Disabling a governor is a good way to scatter an engine, as its main purpose is to prevent over-revving in the lower gears. That's particularly true if you've got a bunch of gears to play with, like a Brownie and/or a 2-speed rear axle. In the first couple of gears, especially on the low side of a 2 speed, the engine will max out the RPM before you can make a shift. Engine torque (or lack of it) usually holds the top end speed down, not governed RPM, especially when hauling a load.
Jerry

as far as im concerned the truck isnt being drag raced so i dont plan on hammering the gas trying to launch the truck causing a need for worry about shifting faster than the engine can rev though you make an exceptionally valid point about over-revving. its a crawler gear to get the tuck and load moving so you dont need a ton of throttle input to just ease it through first gear. 2nd while true lack of engine torque usually limits top speed it seems buckshots "problem" is that no matter what it wont go over 45mph even if he isnt high in his rpm range meaning it should still have enough "umph" left in it to spin up in the final drive his truck appears to be physically limited by a device vs being limited by engine torque.

my 58 viking 60 (6400), 2 ton) weighs about 9,000 empty. (steel dump bed). It has a 327 in it, Ranger overdrive in front of the SM420, and 9r22.5's all the way around. I tow my 7100 pound travel trailer with it no problem. Cruises fine at 65-70 on the flat or down hill (not so much up hill!). I rebuilt the brakes (did not reline shoes, and did not go through the hydrovac, but rebuilt all cylinders and all new lines). Brake and Clutch supply in Seattle can reline the brake shoes, I would imaging there is a big truck brake and clutch supply shop closer to you though.

I have not hooked up a tachometer when driving but I think the governed RPM is pretty close to spec, she's wound out and even for a short stroke V8 it sounds fast enough, torque is not much of a problem with the 7.10 rear end, I know the load of hay is not much for it as it is a grain box and could handle 9000 lbs. of payload without going over the advertised GVWR but it does give me a good idea of it's capability.

The biggest issue I had to cure on my '56 was the old wooden dump bed, pretty dangerous when I hauled gravel, it would creak and groan and bend. Heard stories of them breaking in half (my friend's neighbor had it happen, crushed the back of the cab). So I replaced the entire thing with a good knaphide box and scissor hoist, new pump and control valve, even rebuilt the SM420 and the rest of the drivetrain while I was at it. Pretty solid now.

I'd like a locker for the rear, open diff isn't good in the winter when empty, just spins the right duals. (I live in the mountains, nothing is flat here)

Good thread though.

I don't think there is a locker for old trucks, might try a steering brake on spinning wheel( home made), otherwise get a newer rear with correct bolt pattern, Detrpit Locker.

Ed