I was looking at my running boards last night and saw that they were torn and cracked at both ends where they bolt to the fenders and began wondering why that happened at the same location on both the left and right board.
Then I looked at the way they were originally mounted. The boards were bolted to the frame brackets so they were basically rigid yet the front was bolted to the front fenders which rocked around with the cab and front clip and the rear edge was bolted to the rear fenders which move with the bed of the truck. This system seems like it was doomed from the start because every time the cab or the bed moves (even a little) on their rubber mounts the running boards are being twisted and stressed.

Am I wrong in my assessment of the problem?

If the smart guys here agree with me I have a plan (sort of) to eliminate the twisting motion on my boards (after I do a lot of crack repair)

I think that by adding a third running board mount towards the rear of the board (the original two mounts were right by the cab doors) the board will be solid enough to use and I can leave them unbolted from the front and rear fenders which will allow the cab and bed to move without twisting the running boards to death again (I will allow a 1/8 to 1/4 inch gap to prevent fretting). Does this sound workable or am I just making more work for myself?

Gary

 

Gary,
This is what is missing on most of our trucks I have seen but I think it would solve your problem, at least at the front.

1953-56 Ford F-100 Running Board To Front Fender Grmmet & Bolt

When my truck was together I used fender welting between the rear and the fender and I made 1/4" flat bar backer for the inside of fender and running board and had no issues.

 

Yes, the fenders are not supposed to be bolted solid to the running boards. The rubber isolators Dave linked to go in between and the bolts are just snugged.

 

The kit from Mid-Fifty shows nuts and lock washers but in my experience the nuts work loose. I used stainless ny-lock nuts and never had a problem. I'll be using them again when I finish the total rebuild in progress.

 

Thanks for the information. My running boards were installed wrong at some time in the last 50+ years. Imagine that

I'll make sure to order some grommets before I bolt stuff back together.