How is this possible??

[Northern lights]

I'm planning to do a frame off this winter but before I pull this thing apart, I need to figure out why the box isn't sitting right. The drivers side is good but the pass side, the box is touching the cab at the bottom. The gap between the front of the box and back of cab is exactly 1 inch all the way across and the box-cab fit is good at the top but deviates at the bottom only on the one side. I've taken measurements all over this thing, front to back and underneath but can't find the cause. Thoughts??

[aerotruk63]

Could the cab corner have been replaced incorrectly? Looks like it gradually flares out the last foot.

[TheDark1]

That's what it looks like to me, too.

[Rich 5150 69]

Get some measurements diagonally across the top of the bed, see if they are the same...noted that your right side door trim does not line up either.

[Northern lights]

Originally Posted by aerotruk63

Could the cab corner have been replaced incorrectly? Looks like it gradually flares out the last foot.

It looks like that in the pic but looking straight up from under the truck, the back of the cab is straight along that side and the measurement from the rear cab mount to the back of the cab corner are the same on both sides. Also, you can see that the distance from the back of the door to the back of the cab does is consistent all the way down.

[Northern lights]

Originally Posted by Rich 5150 69

noted that your right side door trim does not line up either.

Part of that is that the doors need adjusting (they are low). One of the things to be fixed when I tear it down.

[Northern lights]

Originally Posted by Rich 5150 69

Get some measurements diagonally across the top of the bed, see if they are the same..

Just checked, they are exact.

[Rich 5150 69]

Check cab mounts and look at the inside to see if there has been metal work on the cab by comparing the two sides at the corners.

[Northern lights]

I have measured from cab mount to back of cab, CM to side of cab, floor to mount on frame, side of frame to side of cab, all measurements same side to side. Did similar measurements on front mounts.

[Rich 5150 69]

After looking at the pics again, it looks as if the right side of the bed has been replaced the body line or maybe its a illusion sticks foward on the lower half, and looking at the view from the top left side to right side stake pocket/head board don`t look right.

[kieth]

Remember you are shooting at a moving target,

first the cab:

1. it could be sitting farther forward or back on the mounts, causing the variation in the distances between the body.

2. The cab mounts may be bent and a different height.

3. The rubber cab bushings are probably worn.

4. All of the above

Learn to think in 5 dimensions forward, back, up down, square to the frame then make sure the bed is square to the frame......then yo get to level everything.......it took us a full day......

The bed:

see all of the above........have fun...............

[Rich 5150 69]

View your truck from the rear at a distance, does the bed sit lower in the rear right side...?

[chad64chevy]

rich, that was what i was going to ask! i think a spacer like a 1/8-1/4" washer in the pass. rear cross sill might help, just my thought when i seen it!!

[protrash64]

Bent bed supports. The frame mounts would be correct but the support is cantilevered off the side of the truck and if it was tagged in the rear it could bend. I made my bed from two trucks and one was wrecked and have this issue as some supports were bent.

My theory anyway!!:lol:

[Northern lights]

Originally Posted by chad64chevy

rich, that was what i was going to ask! i think a spacer like a 1/8-1/4" washer in the pass. rear cross sill might help, just my thought when i seen it!!

I had considered that but then it would bend the body line from tail light to head light. All of the cab mounts are new and I measured the mount height on all four cab corners and the rear ones are the same side to side as are the front ones. The truck is on a 67-72 frame so I checked every measurement I could think of as I feel that this may be the cause. It just buffaloes me that everything appears to be checking out and yet........
I could take pics under the truck if it may help.

[chad64chevy]

hmm., my truck is on a swb 70' frame but i used the steel floor! i had a problem with the driver side top leaning forward and the bottom kicked back! making the driver side not squared, it's still a lil less then a 1/8" off but i had to use different washers on all four corners, i'm not done messing with it but its close!

[Bowed]

Are you sure the right frame rail is not bent from an accident ?

[Northern lights]

Originally Posted by Bowed

Are you sure the right frame rail is not bent from an accident ?

The frame was shortened so there is the possibility that it was welded together crooked, one of the many things to check once the body is off. Even if it IS out, I don't see how it would cause what I'm seeing.

[Captainfab]

This is what I would check into further. I've seen more messed up frame shortening jobs than good ones. Also were the '67-'72 rear cab mount brackets changed for the '63-'66 brackets? They are a little different.

Originally Posted by Northern lights

The frame was shortened so there is the possibility that it was welded together crooked, one of the many things to check once the body is off. Even if it IS out, I don't see how it would cause what I'm seeing.

[Rich 5150 69]

Captain look at pic #2 in his original post, just above the trim on the bed, the bottom portion extends past the top section...or is that an illusion...

[Captainfab]

Yes I do see that now that you mention it. That could be a clue to this issue.

Originally Posted by Rich 5150 69

Captain look at pic #2 in his original post, just above the trim on the bed, the bottom portion extends past the top section...or is that an illusion...

[454stepside]

take a close look at the side thickness of the cab corners the right side bottom cab corner side veiw is wider then the left side. i ran into this problem when i used lmc cab corners i had to pie cut the cab corners cause they were bent wrong and it caused the bottom of the cab corner to stick back to far and touch the bed

to be more clear measure bottom of cab corner at door opening to where the cab corner wraps around to the back of the cab it will be about an inch wider on the right side

[Northern lights]

Originally Posted by 454stepside

take a close look at the side thickness of the cab corners the right side bottom cab corner side veiw is wider then the left side. i ran into this problem when i used lmc cab corners i had to pie cut the cab corners cause they were bent wrong and it caused the bottom of the cab corner to stick back to far and touch the bed

to be more clear measure bottom of cab corner at door opening to where the cab corner wraps around to the back of the cab it will be about an inch wider on the right side

Yup, the problem is in the cab corner. I can actually see it clearly in the pics now. The corners are the same shape and size but the pass side one was not installed properly. You can see that the drivers side is canted inward as soon as it leaves the door which allows the corner to curve in behind the box side. The pass side is not canted and therefore does not curve enough to clear the box. Thanks for the help guys. Much appreciated.