The Stovebolt Site Forums The Shop Area General Truck Talk Boxing frame, need to know what bolts I need to weld..

ive got a 37 1/2 ton. im in the progress of boxing the frame. does anyone know what bolts go through the frame to the bed, cab, or any other brackets mounts. i need to order the kits asap as i have overlooked welding the nuts in until now! i bought the truck in peices so im not sure what exacly I need.

Hey playboy is your truck a chevy or a GMC ?i have shop manual and master parts catologs for both that show the frame and most of the bolts and nuts i believe. i found most of the books on e-bay a seller named crankem hope publishing. if i can be any help email me .Later Earl

Playboy, there's an option you might want to consider, although it is considerably more work.

If you weld nuts or bolt heads to the inside of the frame, box over them, and they strip or break, you've got a problem.

Consider welding a sleeve in between the frame and the box plate. You end up using longer bolts, but you can make them about any size you like, and, if something gets broken or stripped, no big deal.

I don't understand why you wouldn't just drill through the boxed frame and use longer bolts. Is my Alzheimer’s taking hold here? :confused:

You could BUT you need to put a crush sleeve(I guess thats what they're call)which is basicly a piece of pipe between the inner & outer frame rails or as you tighten up any bolts the frame will start to look like this ~~> ) ( ...Joe

Makes sense ZooKeeper, however I wonder how heavy duty do bed bolts need to be on a 1/2 ton. Besides, being boxed you would think it would be D%&@# strong. Still, I do subscribe to the belief that It's better to overdo it than to have to do it over.

On a normal 37 short step, the bed-to-frame bolts are 3/8" X 6" Carriage bolts (qty 6) You would also need offset washers for the wood (1-1/2" X 3/8).
Most bed-to-frame bolts are 3/8" with various lengths depending on the bed.

When boxing a frame I always weld "bolt couplings" where mounting holes were for every item that was bolted to the rails and or frame just in case I ever needed to unbolt something I would never need a hold back.

If your frame is already boxed as you mentioned, enlarge the holes to accept the hex couplings which are roughly an 1-1/2 inch long. Insert a bolt in the coupling and weld the coupling slightly below the the top of the rail. The hex design makes a good area in the hole for weld peneration. TIG and or MIG is best for this task. Take your time doing this and constantly turn the bolt so it will not swell in the coupling. Because the coupling is so much longer than a nut chances are that the threads will never stip. I also use an anti seizing compound on the bolt when welding so the heat will not cause it to swell or seize. If you have the time and equiptment you can make your own coupling to any desired lenth from round stock further assuring stripping the threads, but I think an inch of thread is more then enough. Remember, once these are installed you have no room for adjustment so be sure of where you want to place them.

You could always cut a hole in the side of the already boxed frame to thread a nut the original way but chances are it will require the help of someone else to give you a hold back on the nut underneath the vehicle. If you do this be sure to file the edges of the hole to save yourself or your friend from cutting up your fingers and hands when installing the bolt.

Please feel free to correct me if I'm wrong, but isn't the bed held down by carriage bolts located in offset washers?

How do you plan on spinning the carriage bolts (which normally have the square shoulder on them) in the washer without moving the bed boards around?

As starkweather mentioned above, you may want to drill through the top and bottom of the frame and add his 'crush sleeves' (just use 1/2" pipe cut to fit inside the frame) with much longer bolts so you can easily tighten down the bed.

I didn't box the frame of my '59 3800, but I did add an additional channel that fit within the original frame (see pics here: http://rides.webshots.com/album/561655740knjkhx ). This way, I only need to lengthen the bolts I need by 1/4".

Lane