1957 deuce engine swap, axle ratio change, lowering unit and extending cab

[letssled]

Hello all, this is my first post, but I have been creeping for a while. I have a project that I want to start, but before I lay down some $$$ I would like to hear some opinions/thoughts.

I am looking at purchasing a 1956 GMC m135, stock, with a toasted engine. Body is in decent shape, no major dents, not to rusty.

I would like to:

- pull out the engine and replace it with a 2001 Caterpiller 3126 300 HP and 800 ft-lbs.
- LOWER the unit by over slinging the axles. Has anyone ever lowered this on this type of unit? Would there be clearance issues between driveline and engine? The truck CAN'T be any higher then 7' 8" tall. I would even consider going to smaller tires if it helps.
- Upgrade the brakes to a modern type hydraulic with vacuum assist.
- extend the cab to seat 8 people (2 in front, 2 rows of 3 in the back), put on a pickup truck style box on the back. Retain the stock length.
- Replace the crown and pinion to something around 3.73 or 4.11. I need to be able to do highway speed and then some. 80 MPH tops, but really only cruise around 60 - 65 MPH.

I would not be taking it offroad; ever. It would carry my Polaris RZR 4 side by side and pull my 8000 lb holiday trailer.

Just wondering what your thoughts or tips would be? It would not be used much either, 10,000 miles a year. My family has outgrown an extended cab truck (2 adults, 5 kids). I am a machinist and welder and I have done work like this in the past. But admittedly it will cost a fair $$$. I can get the truck for $4500 and the engine/tranny/rad/brakes, etc are in a 2001 Bus that I will use for parts. $5500 for the bus. So I am at $9000 an haven't start yet.

Thanks,
Ty

 

[hndrsonj]

The GMC and M35 are 2 different trucks.

 

[letssled]

The GMC and M35 are 2 different trucks.

typo, forgot the "1", m135. Here is the truck, tandem axles, single tires.

 

[NDT]

No axle gear sets other than stock are available. The 302 is governed at 3400 RPMs and it takes all of that to get the 135 moving at 58 mph. Gonna take a lot of overdrive to keep the Cat alive at 80 mph you seek. GMCs with bad engines can be had for a lot less in the US.

 

[letssled]

No axle gear sets other than stock are available. The 302 is governed at 3400 RPMs and it takes all of that to get the 135 moving at 58 mph. Gonna take a lot of overdrive to keep the Cat alive at 80 mph you seek. GMCs with bad engines can be had for a lot less in the US.

That is some great information NDT! Thanks so much. I think that axles are going to kill this project right off the star That pinion would probably fail quickly or blow seals regularly.

 

[m1010plowboy]

Canada Deuce, Honk Honk

Welcome to Steel Soldiers!

I really like that truck. I'd also like to see a Cat engine put in it. I've seen Big Block Chev/ Olds, Small block Chev, 6.2 diesel and heard stories about others so anything can be done.

....at the same time I'm on a preservation kick and would hide that one in a barn, it looks good.

Is it anywhere near the prairies or are you like most Canadians and hiding out East in Canada's best rated City?

There's an addict in BC that's on a similar preservation kick so before that truck gets altered....I gotta ask....where can I find her?
PM me, send me a private message, with any details.

A couple of years ago a friend went to Chicago and bought a Freightliner with a condo on the back. Drives the smart car in the garage on the back and has plenty of seat-belts on board for the whole family.

I grew up in a family of 6 so we fit in a car. Having 7 folks to stuff in a vehicle is not going to be easy. Have you thought of an airliner?

 

[rustystud]

Hello all, this is my first post, but I have been creeping for a while. I have a project that I want to start, but before I lay down some $$$ I would like to hear some opinions/thoughts.

I am looking at purchasing a 1956 GMC m135, stock, with a toasted engine. Body is in decent shape, no major dents, not to rusty.

I would like to:

- pull out the engine and replace it with a 2001 Caterpiller 3126 300 HP and 800 ft-lbs.
- LOWER the unit by over slinging the axles. Has anyone ever lowered this on this type of unit? Would there be clearance issues between driveline and engine? The truck CAN'T be any higher then 7' 8" tall. I would even consider going to smaller tires if it helps.
- Upgrade the brakes to a modern type hydraulic with vacuum assist.
- extend the cab to seat 8 people (2 in front, 2 rows of 3 in the back), put on a pickup truck style box on the back. Retain the stock length.
- Replace the crown and pinion to something around 3.73 or 4.11. I need to be able to do highway speed and then some. 80 MPH tops, but really only cruise around 60 - 65 MPH.

I would not be taking it offroad; ever. It would carry my Polaris RZR 4 side by side and pull my 8000 lb holiday trailer.

Just wondering what your thoughts or tips would be? It would not be used much either, 10,000 miles a year. My family has outgrown an extended cab truck (2 adults, 5 kids). I am a machinist and welder and I have done work like this in the past. But admittedly it will cost a fair $$$. I can get the truck for $4500 and the engine/tranny/rad/brakes, etc are in a 2001 Bus that I will use for parts. $5500 for the bus. So I am at $9000 an haven't start yet.

Thanks,
Ty

Why not just use the bus ? You will spend so much more converting this old truck to something that any modern truck or bus could do now. Save the truck for a collector and not destroy it. Get a bus and convert it ! Used school busses are cheap and easy to convert.

 

[M543A2]

I agree with Rustystud. You are not spending money wisely to try the conversions. You may get tired of it long before you are done and a nice truck is destroyed! The old GMC axles are not as tough as the M35 deuce axles and not as tough as most civilian axles because for one they have ball bearings on the pinion shafts. I have blown these even with proper maintenance. Looks to me to do all you want to successfully you would be throwing away almost everything but the frame and cab!

 

[letssled]

Why not just use the bus ? You will spend so much more converting this old truck to something that any modern truck or bus could do now. Save the truck for a collector and not destroy it. Get a bus and convert it ! Used school busses are cheap and easy to convert.

I know busses are cheap, but a bus is still a big old ugly bus.....Plus I won't have 4x4, er,well 6x6 either; I love the look of the single tired 6x6 trucks. I get you want to preserve an old truck, but watching it rust away in a field isn't going to save it either. m35 and m135's are not common at all in Canada, nor are parts. But I think the Rockwell axles/or and the GMC axles are going to kill the project. I don't think the pinion is going to like the high sustained speeds from the GMC axles, nor can I get any after market parts . Putting in Rockwell axles probably won't allow me to lower the truck enough. Thanks for the thoughts, comments and info!

 

[The King Machine]

I know busses are cheap, but a bus is still a big old ugly bus.....Plus I won't have 4x4, er,well 6x6 either; I love the look of the single tired 6x6 trucks. I get you want to preserve an old truck, but watching it rust away in a field isn't going to save it either. m35 and m135's are not common at all in Canada, nor are parts. But I think the Rockwell axles/or and the GMC axles are going to kill the project. I don't think the pinion is going to like the high sustained speeds from the GMC axles, nor can I get any after market parts . Putting in Rockwell axles probably won't allow me to lower the truck enough. Thanks for the thoughts, comments and info!

Where are you in Canada?


I know of a local 1994 M35a3 for sale, it already has half the stuff you want to do to that truck.

 

[letssled]

I agree with Rustystud. You are not spending money wisely to try the conversions. You may get tired of it long before you are done and a nice truck is destroyed! The old GMC axles are not as tough as the M35 deuce axles and not as tough as most civilian axles because for one they have ball bearings on the pinion shafts. I have blown these even with proper maintenance. Looks to me to do all you want to successfully you would be throwing away almost everything but the frame and cab!

Where are you in Canada?

Thanks for the heads up TKM, sent you a pm.

 

[11Echo]

I know busses are cheap, but a bus is still a big old ugly bus.....Plus I won't have 4x4, er,well 6x6 either; I love the look of the single tired 6x6 trucks. I get you want to preserve an old truck, but watching it rust away in a field isn't going to save it either. m35 and m135's are not common at all in Canada, nor are parts. But I think the Rockwell axles/or and the GMC axles are going to kill the project. I don't think the pinion is going to like the high sustained speeds from the GMC axles, nor can I get any after market parts . Putting in Rockwell axles probably won't allow me to lower the truck enough. Thanks for the thoughts, comments and info!

Lot's of videos of buses running Rockwells at Yankee Lake.
Look for them on Youtube.

 

[m1010plowboy]

I found the ancient link to the 502 Big Block, 75 MPH early deuce. Not many pictures but I bet it's still around.

http://www.steelsoldiers.com/showthread.php?2932-California-Hot-Rod-M211