Hey everyone, new to stovebolt. Recently purchased an awesome 42 chevy dump truck that has set since 1959. Drove 5000 miles round trip to pick it up in Great Falls Montana and bring it back to NC. Having a great time bringing it back to life. Found that the flywheel gear had broken, possibly the reason it was parked. Originally was red with black fenders but has been painted military green at some point inside and out. Don't know we're it severed but assumed it was used state side during WW2. Still quite a bit of green on the interior with a great mixture of red, black and green outside. On my first stop on the way back I took the oil cap of and filled the motor with diesel until it ran out of the canl vent and pulled the plugs and sprayed the cylinders wit PB blaster. Got it back when I rolled it off the trailer, popped the clutch and it turned over. After some wiring and a new battery found that the flywheel gear was broken. Tack welded it back to the flyw3 temporarily to see if I could get the motor started. After unsticking some valves, carb and fuel clean out and a tune up it fired up, runs great. Pulled the tranny and replaced the gear, clutch, pressure plate and throw out bearing.. Now it moves on it own for the first time in 60 years. Just started on complete brake rebuild. So after all of that this is my first question I hope someone can help me with. It has a two speed axle that is shifted with a second shifter by a cable. Not sure how to use it. Know about electric shifters but not these.. Do you shift the same as an electric? Shift on the fly up and down as you would a later model axle? Don't want to tear up the rear grear. Thanks for any info you might have.
Hy Gulfsuper, welcome, that sounds like a great project you have there. Am I correct in my assumption that your truck has a Timken double reduction two speed differential? I have seen those differentials shifted by rod linkage, cable linkage and vacuum diaphragm, but I have yet to see an electric shift unit. Good luck with the rest of your work.
Thanks Master Gabster. Believe you are correct on the double reduction. Do you shift it the same as later two speed axle? It has a four speed gear box. Do you change the axle as you go through the gears?
Stop over in Missouri for tires. Nephew works at country tire store. Tires had to be cut off, he said don't bring it back. Have other pictures but files are too big
Home. Figure there were 60 generations of mice. Four large trash bags of mouse nest. It was every were including the radiator and thermostat housing. No radiator cap.
New master and wheel cylinders. New rubber hoses. Remaking all the steel lines.
Shoes are being relined.
Replacing all bearing seals.
Amazing how good the old brakes were. Other than one rear brake being coated in rearend grease due to seal failure, the looked like it was parked a week ago Drums are in great shape no grooves, just need a light sand. Shoes still had good pad. Somebody took good care of this truck and kept up with maintenance.
Although I removed the system too far gone. It had an air over hydraulic system with a second master cylinder in the rear.
Been following with great interest. Concerning its "Military service"....... in addition to the OD green paint, I believe the front fenders have been "bobbed" or trimmed for more clearance.....possibly to clear 10:50 x 20 tires popular at the time....... have you made any comparison with a similar civilian model???
Got some new questions for you guys. The current engine I found out is a 54 235 pressure engine. It runs really good but has a crack in the block under the manifolds that runs 3/4 the lengthy of the block. I cleaned it up good and put some JB weld on it. Since it is not a pressure system it did a good job of slowing it down and shouldn't be a problem for the amount of us it will get.
That being the case I am going to start working on a replacement engine. It is not the original so no need to worry about saving this one.
So the two choices I am considering are, building an upgraded 235 for more horsepower and torque. Or going with a small diesel, possibly a 471 Detroit. Though about a 3126 Cat but no way I can get it to fit, just to big. Definitely not looking for speed, more torque and pulling power.
Does that cable shifter happen to be spring-loaded so there can be a "pre-select" of the rear end shift and then a quick unloading of the drivetrain by pushing the clutch pedal or backing off the throttle when shifting the rear axle? A trucking company in California where I ran the maintenance shop had an old frame with that type of manual-shifted rear axle.
A 261 engine would be almost a bolt-in fit if you're looking for more power, but anything newer will require some major fabrication. I'd suggest a 292 and a SM-420 transmission, if you think the rear axle will stand up to the added torque and horsepower without needing a trip to a dentist to get the gear teeth patched up! Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
Think the rear end would handle the additional torque, really heavy duty. Had thought about a 292, had a 64 mechanic truck with a 292. Could probably get some pretty impressive torque out of it. Not familiar with that trans, will look in to it. Fabrication not a problem, love that stuff.
From what I understand at this point, the 453 detroit needs multi speed transmissions because of the narrow power band. Is that correct?
All Detriots have a narrow power band- - - -usually 1750 to 2150 RPM, so you need a gear for every 400 RPM. The oldtimers who drove Detroit inlines, 4-71's and 6-71's especially, used to talk about "rowing it with the shift levers". If you like getting your exercise by grinding gears, go for it!
Those engines are incredibly heavy for the power they produce, and your truck is too small to make a good platform for using any of them. The only thing better than a 292 as a swap would be a Ford 300 inline six. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
The 53 series are governed at 2800 RPM, which still isn’t a lot but gives you around 1100 RPM power band. You can use the calculator on 4lo.com to calculate your gear ratios and rpm at any given speed.
I don’t think a 4-71 would fit. It’s 40 inches long and weighs in at around 1700 pounds!!
I’d personally go with a 3-53T. There are bellhousing a available to run an NV4500 behind one.
Sorry, couldn't go ford always been a chevy man. Seen a 453 in a similar chassis. Google 453 runaway. Would be a tight squeeze. Found specs on Detroit deisel motor. The 471 is actually shorter than the 453 ( 36/39).
Could probably get them in but starting to lean back to upgrading a stovebolt. You think it is worth trying to find a 261. Would it be that big of a performance jump from a solid 235? What are some of the tricks to getting a torquie motor Also I live in the mountains of NC. Would like to improve engine breaking, that was one reason looking at going deisel.
A 261 c.i. would be a good choice. With a headers, bulldog cam and multi carb setup you can get a respectable amount of torque which with the 2 speed axle should give you all the gearing you need plus good engine braking.
A radical cam and multiple carburetion kills the torque, except at wide open throttle. Run a 261 "as manufactured"- - - -the engineers who designed it for big truck use were smarter than a bunch of guys who have read at least two copies of Hot Rod Magazine and attended a swap meet recently! Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
The 2 speed diff on my 46 2 ton has the vacuum shift and works great, just shift it and lift on the gas to make a little slack in the drive train. The only time I use it is to down shifting going around a corner. It doesn't grind at all like the tranny does down shifting into 3rd. A big project you have there, looks a lot like mine did 15 years ago. The thing that probably saved both trucks from the crusher is the glass stayed in them during the rusting process!
Last edited by Chris's 46 / 515; 12/13/20204:34 PM.
This one is a cable shift. Tried to shift at low speed. Came out find, had to stop to get it back in. Yeah the glass, all the grease and oil that was never cleaned of and being in Montana. Never knew that Montana had such a dry climate.
Will give it a try. Anyone have a line on a 261. Getting hard to come by. How much of a mod would it be for a 292. What is a good synchro tranny? Would need pto for dump pump.
Hotrod lincoln, these big trucks have all the low end torque they need through the low gearing, a bulldog cam is not even close to being radical, mainly longer duration. Mid to high range torque is a big help when pulling hills with a load and a better breathing engine is always a plus. Talk to Tom langdon at langdon stove bolts, he was a engineer at chevrolet for years and is a authority on chevy six cylinders
Thanks, will reach out. Have really been surprised how much torque a 235 that hadn't run in 60 yrs has. It really has some pretty good low end torque. Pulled some pretty steep grades in third gear on the high side of the rear axle. Lugged really good.
Gulfsuper Great truck !! Never did hear anyone try to help you with your 2-speed shifting. I think you will find if you take-off in low axle then shift your control-with tension (power)on the driveline when you let-up it will shift to high axle this would be in high gear. Maybe at 25 MPH next to downshift just slow down to 10 MPH or less with tension on shift and when you let-up will go to low axle. You can then learn to 'split shift' your gears when loaded !!! Big Fun for Big Bolters !!!
Unloaded is often to just shift to high when at cruise speed like fixite7 said rather than shifting the two speed several times, use the two speed when loaded.
Ed
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires. '47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle. '54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed. '55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
