Stepside box widths

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May 26, 2008 | 12:04 AM

Tha_Stepside

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Stepside box widths

Hey y'all, i have a 78' F150 Stepside that I have been restoring. The box was literally rotting off and I couldnt find a used one in decent condition to rebuild, so i went to LMC and ordered all new box sides, all new rear fenders, and the front sill from a 72'. I made a custom solid rear sill, and laid a 1/4" steel sheet down instead of the wood bed, now I have mounted everything up right and made some custom cross sills to mount the new box. I put the rear fenders on and realized the wheels and tires are sitting probably 2-3" wider than the outside of the fenders. I dont recall the tires (35X12.50X15) ever protruting that far out. I was just wondering if there was any difference in the widths between the stepside boxes throughout the years, i believe the inside diameter of my box is 48 inches. Any help would be great, thank you.

May 26, 2008 | 07:13 AM

Pro-Street/StateTK

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From: East Flat Rock NC

tha-stepside

There are different widths the long beds of early models were wider!
Do you still have the tailgate for the '' 79 step bed '' compair it to the 72 front sill and front panel, I think you will be using a 55-72 tailgate, for this all to work?
Is your new bed sides have the flat bed tops or 45 degree?

P.S. keep in mind the tires sit close to the edge of fenders, and with beefier
tires they some time protrude out!

Wally Womack

May 26, 2008 | 08:00 AM

Tha_Stepside

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actually, i never had a tailgate with my original box. But i did manage to buy an old tailgate from a friend who said it was off of a long box, i figured it would fit. I was wrong, its about 6" too wide. I got the box that has the 45 degree slant at the top of the box, i couldnt find any company that made the 90 degree box sides.

May 26, 2008 | 04:43 PM

rickh51

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The inside to inside measurement on my '78 stepside box is 54". The tailgate measures 55" outside to outside. Maybe someone can measure their earlier box and give you the dimensions of theirs. I don't know how wide your wheels are, or what the backspacing is, but you could get wheels with more backspacing to move the tires in a bit farther. Just a thought, ya know?

May 27, 2008 | 12:10 AM

Tha_Stepside

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Hey guys, thank you for all your help. I was wondering why the tires protruded out a little more than i could remember from the original box (scrapped over 2yrs ago). I guess the 72' box is a little thinner, no problem im just going to have a sheetmetal shop extend the fenders 3" and all shall be good. The wheels and tires on it just look too badass to change. Anyways heres some pics of what it looks like, feel free to criticize as its still in the customizing process

May 27, 2008 | 11:05 AM

Pro-Street/StateTK

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From: East Flat Rock NC

You may want to look for the front panel from a long bed stepbed 61-72 or make your own panel, since you have the tailgate from a long bed. That would bump your bedsides out roughly the 3 inches each side that you are talking about having added to those brand new rear fenders.

Also there are some stepbeds that had bolt in/weld in inner fender wells.
Dan Carpenter sells both the bolt in and the weld in, if your bedsides get bumped out to far and cause clearance issues between the bedside to
the inside of the tires.
Some 75-79 stepbeds had these factory.

This may create an issue with your steps. Some people say the steps are all
the same, I know they are not, but I dont have the measurements on them.

Wally Womack

May 27, 2008 | 11:30 PM

Tha_Stepside

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I actually baught a set of longbox 73-79 steps, and am in the process of shortening them, its no big deal, just more body work. I dont have the detent on the bedsides, and with all the work in welding in teh solid 1/4" steel bed, i doubt im going to be putting in the wider front sill. I think im just gonna pay a body shop to add a couple inches to the fenders and call er' a day. Actually i think that would make for a "unique" "Flareside" ford, not too many 4X4's out there with widened fenders, and i think it would add to the "BADASS" look that im looking for out of this truck.