[GB SISSON]

There are multiple wood crossmembers. They tuck under the 8' long side strips. The crossmembers sit on the frame rails at the drilled holes and have a 1/8" notch on the top side where they tuck under so the 1 1/8" boards lay flat. I use full 2" for crossmembers as that's about what I have found upon dissasembly. The two crossmembers that are mounted on the raised axle hump area are wedge shaped in cross section. perhaps 1 1/2" on one edge and 1" on the other. I tend to keep the main crossmembers 3"-4" wide. I have used 2x2 1/4" wall square tubing for the front crossmember on two of the tonners as it affords a great stiffener and repair for the front panel which is often compromised at the bottom. Welding the panel to this straightens it nicely and makes thgat area bombproof. You may find that when using full 2" crossmembers the rear factory stamped steel crossmember sits above the frame rails. Since I save big truck mudflaps and rubber conveyor belting I always come up with something that'll tuck under there to raise it up a bit. I like to mechanically repair my trucks and make them solid and safe while they appear unrestored. This tonner in the pics was built from numerous green jailbar trucks I had accumulated for parts, and is intentionally a beater, so I used a mix of weathered but sound planks gleaned from the salvaged wood side of my business. No varnished red oak and stainless strips spoken here. Fortunately I've had friends drop off black locust logs for me to mill and I squirrel away any 5' cuttoffs for those wood crossmembers when I can. Hope this helps! There is probably more shots and details of this truck and it's bed on my thread here called 'Winter without a project?'