Bumper & Frame Issue

[firebane]

Dude! You have nothing to say that your frame is bent. All you have shown is that your suspension and body is not even with the frame. So how do you expect to have your bumper line up with the body when the body doesn't line up with the frame because the bushings are shot?

Then please explain to me how the two bottom holes for the bumper do not line up. Lets take the body completely out of this all together and focus solely on the frame itself.

With only the frame in play and looking strictly at the front of the truck at the frame horns please explain how the holes are not lined up perfectly?

If I took the body off the truck the bumper still would not line up properly and be level because the frame holes are out alignment.

I'm trying to figure this out but everyone wants to go strictly to the body and body mounts which won't make difference to the alignment of the frame. Its not like swapping out body mounts is going to magically make a frame line up.

 

[firebane]

Your just in denial that you need new body bushings! LOL

No trust me I know I need body bushing I am doing one thing at a time and right now I want my bumper to fit and be proper.

 

[MadOgre]

Then please explain to me how the two bottom holes for the bumper do not line up. Lets take the body completely out of this all together and focus solely on the frame itself.

With only the frame in play and looking strictly at the front of the truck at the frame horns please explain how the holes are not lined up perfectly?

If I took the body off the truck the bumper still would not line up properly and be level because the frame holes are out alignment.

I'm trying to figure this out but everyone wants to go strictly to the body and body mounts which won't make difference to the alignment of the frame. Its not like swapping out body mounts is going to magically make a frame line up.

Ok. So your measuring from the ground to the frame horn. The problem is that any variation from side to side in the suspension and or tires and or bushings and or wheel bearings. will affect that measurement from the ground. The rear suspension will affect it as much as well. So by measuring from the concrete to the frame horns is only telling you that your suspension is probably not even from side to side in both or the front or back.

You would have to put the frame on a jig to be able to tell if the frame is bent or not.

What you do know is that the body is not evenly parallel to the frame and thus it is obvious that if the bumper is mounted correctly to the frame that it will appear crooked in relation to the body. Seeing ass the frame is not sitting parallel to the ground either for undetermined reasons, the front bumper will not appear to line up with anything.

 

[firebane]

Ok. So your measuring from the ground to the frame horn. The problem is that any variation from side to side in the suspension and or tires and or bushings and or wheel bearings. will affect that measurement from the ground. The rear suspension will affect it as much as well. So by measuring from the concrete to the frame horns is only telling you that your suspension is probably not even from side to side in both or the front or back.

You would have to put the frame on a jig to be able to tell if the frame is bent or not.

What you do know is that the body is not evenly parallel to the frame and thus it is obvious that if the bumper is mounted correctly to the frame that it will appear crooked in relation to the body. Seeing ass the frame is not sitting parallel to the ground either for undetermined reasons, the front bumper will not appear to line up with anything.

Exactly something in the frame whether it's suspension or the frame itself is causing this issue.

And to figure out that issue it needs to go on a jig or the frame on solid ground with all 4 tires suspended.

 

[MadOgre]

Exactly something in the frame whether it's suspension or the frame itself is causing this issue.

And to figure out that issue it needs to go on a jig or the frame on solid ground with all 4 tires suspended.

Ya so replace the body bushings, then get a new non bent front bumper and things will start to line up!

Im almost positive that your frame is NOT bent!

 

[Georgeb]

How far off is the hole? 1/2 the hole? Not visible through the bumper at all? Were there bolts in it when you took it off?

 

[chengny]

How about your rear suspension? Consider this:

It appears that the difference in height between the two bumper mounting holes is about - what...maybe 1/2" max? A frame is essentially just two parallel lengths of channel that are mounted on the front and rear axles (with leaf springs between the axles and the rails).

Ignore the crossmembers for the sake of this discussion - they really provide no structural strength in the vertical plane (i.e. they do not maintain alignment between the height of the two channels).

Your truck has a wheel base of about 11 feet - with another three feet or so of the frame rails cantilevered out - forward of the front axle.

If you consider the front axle/spring group as a pivot point - and imagine a force pushing (either up or down, depending on the side in question) - all the way back at the other end of the channel - at the rear axle....how much would that rear end need to be moved in order to cause the end at the front to rise or fall only that 1/2" difference.

Given the right circumstances, an inch of vertical change at the rear would probably result in about 2 inches of movement at the opposite end of the rail. And your bolt hole misalignment is not even that bad. Its possible, I think - and I'm not saying it is the problem - that you might want to check the rear ends of the rails for even distance from the rear axle mounts.

 

[firebane]

How about your rear suspension? Consider this:

It appears that the difference in height between the two bumper mounting holes is about - what...maybe 1/2" max? A frame is essentially just two parallel lengths of channel that are mounted on the front and rear axles (with leaf springs between the axles and the rails).

Ignore the crossmembers for the sake of this discussion - they really provide no structural strength in the vertical plane (i.e. they do not maintain alignment between the height of the two channels).

Your truck has a wheel base of about 11 feet - with another three feet or so of the frame rails cantilevered out - forward of the front axle.

If you consider the front axle/spring group as a pivot point - and imagine a force pushing (either up or down, depending on the side in question) - all the way back at the other end of the channel - at the rear axle....how much would that rear end need to be moved in order to cause the end at the front to rise or fall only that 1/2" difference.

Given the right circumstances, an inch of vertical change at the rear would probably result in about 2 inches of movement at the opposite end of the rail. And your bolt hole misalignment is not even that bad. Its possible, I think - and I'm not saying it is the problem - that you might want to check the rear ends of the rails for even distance from the rear axle mounts.

Hmm you've given me some things to consider.

Theoretically your saying that if I lifted up the rear frame rail on the driver side that the front should move down? If that did happen then what? Is that saying the springs are the culprit in the back?

If YOU were to do those rear measurements where would you do them?

 

[firebane]

I was just thinking of something. When I put the lift in I only measured one side. If there was any difference in the frame then it would should in all 4 corners measuring from axle to bottom of frame correct? And if there is a difference then that would also signify that there is a problem with with the suspension somewhere?

 

[chengny]

You must be registered for see images attach

 

[Georgeb]

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Is that a stack of books on the floor jack?

 

[Old77]

I think it is, george, and under the jack stand out back on top of the rim whatever works them parts manuals are near useless sometimes anyway. lol

 

[chengny]

Yeah, those are some old study guides. When necessary I always use old books to increase the effective height of a floor jack/jack stands. It seems to annoy people, but I find that books are extremely stable and the paper is virtually incompressible. They come in many different thicknesses so that I can dial in the height of a jack stand to exactly what I need. Best of all - they don't cost 'nothin.

 

[firebane]

Ah yes ok that is perhaps what I thought you meant. I'll do up some measurements tomorrow after work and report back.

 

[MadOgre]

I was just thinking of something. When I put the lift in I only measured one side. If there was any difference in the frame then it would should in all 4 corners measuring from axle to bottom of frame correct? And if there is a difference then that would also signify that there is a problem with with the suspension somewhere?

At any rate if you install new body bushings and install a straight bumper the bumper will line up with the body. I can tell from the pictures that your suspension is not even all the way around. You'll just be chasing your tail unless you install new quality leafs on all 4 corners.