I have a 1951 6400 series 2 ton. It's currently a 161" wheelbase grain truck with a dump bed . I may be losing my storage place for this old truck, so I am weighing alternatives to keep it in my home's 2 car garage. Has anyone here "shrunk" a 6400 model 161" wb down to a 6100 model 137" wheelbase? Better yet, the closer to a 110" wheelbase C.O.E. 5100 model would be great. My desire is to have more of a Road Tractor version of this truck (aka ... semi-trailer truck). {Note: I am not likely to put a 5th wheel coupling on it , but instead simply rig a Class III hitch to it}
It usually involves shortening the frame. Best to find the straight, non-tapered section in the middle, that way one retains all the axle and brake fittings. Sleeves can locate inside or outside the frame, and should be tapered at the ends to prevent the stress all being at the ends of the sleeve.
This is something most anyone can do, except for bending the sleeves. All kinds of procedures are followed.
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.
One, cut the frame, weld and plate. Many ways to do this, but General Motors has a best practices way to do it, and if I was going to do it, I would do it that way. It's a free download. If you can't find it, I can.
Two, cut, pound or drill out the rivets in your rear suspension and move it forward. Easy with a straight frame, not so with a tapered frame, but can be done. This is the strongest and straightest if you drill the holes correctly. Good bolts, and ream to fit.
Both ways, obviously, you will need to shorten your driveshaft. I would have someone do that and get it balanced. Not sure I want to be chasing a vibration problem in the future.
I am going to move the axle forward on my 65 GMC 5000 a couple feet this fall, but I am going to replace the leaf springs with a air set-up from a IH truck. Keeping my axle and hyd brakes so everything works the same. Just adding a electric air pump and tank. Air ride..
Good luck with your project,
BaconFarms
1948 GMC 2 Ton 1958 GMC 370-8 1965 GMC 5000 1970 Chevrolet C50
My '59 Viking 40 started out as a short wheelbase 1 1/2 ton and was stretched at some point to accommodate a 12' stake bed with hoist. So, I'm sure that it wouldn't be that difficult to do. Shorten the frame, bed, drive shaft, brake lines, wiring etc.
Ed, Bacon & John --- Thanks so much for the ideas! I have had this big truck about 10 years, my neighbor (previous owner) purchased it new. I'm getting kinda up in years , and this heavy truck is ... well, getting heavy for me to handle. I am facing the dilemma: if I loose my storage in the old machine shed, then I have to move it 12 miles home and stick it in the backyard. Backyard big truck repair and maintenance is something that I enjoyed more in my youth. I have been spoiled later in life by keeping a truck in garage. It looks like if shortened to 137" or less wheelbase (about 19feet long bumper to bumper and 81" tall to cab top) it could fit OK in my 2 car garage.
I have driven "shortened" 1948 & 1952 Chevy COE's in workyards years ago. Guys would take a big old AD farmtruck & cut sections from the frame rails and reweld , shorten the driveshaft, and since it was yard truck work, they would not re-connect the rear brakes ; but simply use the fronts and the hand band-brake on the driveshaft (these yard donkey trucks didn't run the roads much, and if so only under 25 mph). Those shortened trucks used as tow-tractors and as a platform for winches and generators were amazing.
So starting the thought & measuring process: A) Pick a section of the frame rail not tapered, and where where the front mount of the rear leaf spring is already attached (or plan to drill a new leaf spring front mount) Measure inside frame rail for "sleeves". B)See how much the drive shaft would need to be cut and re-welded (and balanced) C)Plan removing old grain dump bed (raise bed up , lower on 55 gallon drums, pull truck from under bed?) C) New rear brake lines. D) New tail light/ brake light wiring.
(Bacon, I am still moderated and thus unable to post pics)
I have a 53/5100 COE with the 110" wheelbase. I'm pretty sure it was used in its first life as a road tractor, transporting cars. I love the short wheelbase. Still can't get it in the garage because the cab is almost 8' high and my door isn't? Mine is now fitted with an 8' dump bed. If you put a conventional cab on 110" chassis, you wouldn't have much more than a 4-5' stub to the rear. Might make a nice looking tractor. Good luck with it.
CmdrGeo : Nice truck you have. As a kid, I grew up near the old Chevrolet car&fisher&vette/ truck plant in North St. Louis. Chevrolet would use those AD & TF COE's as haulers for both new cars and trucks alike. I remember seeing many of those AD COEs parked in the staging lots awaiting loads after final assembly. It is still amazing how much of load those old 235 engines could haul! {I now wonder if they were 110" or 134' wheelbase.} I once had an AD 52' Chevy COE that we used to take the front tire/wheels off and use wheel dollies just to lower it enough to fit under the garage door header. It was a hassle , but it got it out of the weather to work on.
From the engineering diagrams in the Chevrolet restoration packs, it looks like the conventional cab AD big bolts mostly only came shortened from factory to 137" wheelbase . Is suspect this was primarily because most "trailers" that would be towed needed that extra area space behind the conventional cab to accommodate the front of the trailer. The COE extra sub frame on top of the standard frame sure helped to shorten that wheelbase.
My 42 1.5 ton Flatbed was a full size stake bed truck when I purchased it. I didnt do any modifications to the wheel base but I did cut 4.5 ft off the end of the bed/frame and 6 inched off each side. It now fits in my garage and looks way better. took the full stake railing off and made a step down side rails. Good luck
GreggE, I will go out and re-measure the end of the bed/frame to see if I could fit it in my garage with that simple section cut down.
I did measure my garage door header height at ~82 inches and that includes clearing the lever for the garage door opener. My truck with 7.50-20 front tires (and letting out a bit of air pressure) has a measured cab top of max ~78"-79" so I am pretty confident I could get the cab clearance OK.
I also crept around the floor and tried to comprehend cutting out 24" to 30" of the frame rails. The second crossmember, and the fact that the truck has two piece drive shafts, lets me wonder if just using that 1st drive shaft would couple its' U-Joint to the existing differential.
Anyone here with a 137" wheelbase 2ton AD that can look at their drive shaft (propeller shaft) length for me? {The 1929-53 Master Parts manual and 1949-54 Truck Assembly manual are close , but not that clear regarding the 1st driveshafts' length)
The 137" wheelbase still has a two piece driveshaft, the rear shaft is same (or close), front gets shorter.
Shortening the frame is a lot of work, and usually detracts from the value of the vehicle, even if done really well. I know in my past hunts for old trucks I quickly passed by trucks with modified frames, unless perfect otherwise I suppose.
If there's any reasonable way you can keep the truck much like it is I think you'll be better off all around.
Soggy I could get you photos of where I cut the end of the bed and frame off. Love the truck now, the only thing I need to do is remove a couple of lief springs to soften up the ride a bit. It was a simple job, just had to remove all the planking from the flat bed cut and narrow it, then reinstall the planking and build back the step side railings.
Not exactly on topic but a curiosity question. Years ago when the Dallas Cowboys built their Irving stadium they nearly shared parking lots with Yellow Freight which at the time had the largest freight dock in the world. As we walked to the stadium they had impossibly short tractors spotting trailers up to the docks. Just a single cab like a crane or drag line and gearing so deep that the Detroit Diesel in them would sound like the truck was doing 70 when it was doing 17. Those spotters were GOOD; each trailer had 1" distance between it's side marker lights and the trailer next to it and each got stopped about 2" from the dock and all done at a break neck speed. I've always wondered if these were shop made or if a company made them with the cab, hydraulic 5th wheel,etc.
Grigg: you bring up an important point regarding "value". I was trending toward thoughts that shrinking that 2 Ton would make it more valuable to me, this allowing me to pour a little more money and time into it. I think that the cab and front clip can be restored/refreshed/preserved for a similar price to a smaller 1/2-3/4ton etc because those smaller trucks include such a nice detailed bed (that can cost a pretty penny to get looking straight and shiny)
As it sits, it was past tense good for hauling grain from the fields about a decade ago, and I did use it to haul wood and big metal locally. But the shear size of the truck doesn't lend itself to easy parking, or easy driving in city, nor finding a shelter to keep it from the elements. It's like trying to keep an elephant as a pet.
I have the truck in our old circa 1953 machine shop building that was used to build drag racing cars. The machine tools are long gone, but the building does have a thick concrete floor and an I-beam overhead trolley. The city has grown up around the building and there is a 4X4 specialty builder shop next door, and few garages close by. I am getting a bit too fragile to do such massive work as cutting the frame, but I will talk to a few of the younger mechanics in those shops to see "if" they could cut and weld the frame to a detailed spec. in either in my old building ,or in their nearby shops.
Besides reducing the cost to spiffy up the looks, I was thinking that removing the bed and reducing the overall length would make the truck easier to haul (as a work in progress) from place-to-place on a shorter trailer and with less of a needed tow truck. {last time I moved the truck was with a big dually).
GreggE: yes, I would like to see the way you shortened that bed & frame and pics would be super.
coilover: It is amazing to watch such big trucks zip around like golf carts ! I have an old color brochure book of Fruehauf Trailers and Special Equipment from the AD Stovebolt period and its so neat to see all the aftermarket stuff that they could put on such relatively low horsepower big trucks. I can just imagine what what a Detroit Diesel powering a stubby truck could do.
