What's wrong here?

[CVA59]

OK guys, the only 1966 part on this truck is the frame itself. The front end is from a 1986 Suburban donor and has been 100% rebuilt. The is a nearly perfect cab with new cab mount bushings it is sitting withing 1/8" of being 100% plum to the frame rail. However, the problem is the pass front wheel is offset outward almost 1-1/2" as opposed to the drivers side front wheel. Both rims are a matched pair and brand new. We have measured the cab to the frame and no matter where we take a measurement it is never more than 1/8" out. When we measure the outside front fender lip to the center of the wheel hub the drivers side wheel is as i say, offset almost 1-1/2". Can someone please offer up some input on this because dad and i both have measured and measured everything 1000 times. The only thing different is the fenders in relation to the wheels. We checked the a-arms and it has already been 4 wheel aligned. Ideas, suggestions, input???

Thanks

[LT1 Burb]

I would have to say it looks like a hub problem if everything else matches up. Either a wheel bearing is hung up from going all the way on or maybe a chinese spindle that is different.

[Rich 5150 69]

Lay a straight edge across your fenders horizontally about half way down the wheel opening, lay another one vertically to the top of the fender in the center of the wheel opening, measure the distance from the inside edge of the fender (top ) to the vertical straight edge and see if they are the same, one fender may bowed out and the other bowed in....just a thought.

[CVA59]

The rotors are set in place, we checked that too.

We put a 4 ft level vertical against the outside front fender, got it level and took a measurement to the wheel center hub on both sides. The pass side was 1-7/8" and the driver side was 3-1/4".

Honestly i think the frame is bent as bad as i hate to say it. However, i can find no evidence where the frame has ever been damaged.

[Shooters_7]

I have a spare frame if thats what it turns out to be for a SWB. Good luck and hopefully its something else!

[Shooters_7]

Does it track "true" going down the road or is it kinda crooked?

[LT1 Burb]

You should be able to see a bent frame, look at the rails right where the crossmember is bolted .If it is bent it usually buckles there first, you would see a buckle along the frame rail somewhere if it was bent.

[Alan's Classic]

Have you measured the length of the A arms?

[CVA59]

Thanks shooter. I have been all over this frame and i cannot see anything would convince me it is bent. I have not been able to drive it yet to see how it tracks. This is really mysterious to me since i have checked everything including the fenders and yet i cannot find out why.

Alan.... No i have not checked each a arm. I have measured them from the frame to the center ball joint (grease zerk) and both sides side are identical.

No sure how well you can see this in the pictures but in person it is very obvious.

[low79fx]

Isn't the wheel track width for 73 and later models 1 1/2" wider on the rearend as compared to the 72 and earlier. If thats the case wouldn't the wheel track on the front end rolling gear be the same on the later models.Would there be any way to shim the crossmember assembly 3/4" towards the driver side to get it centered? Maybe IDK?

[CVA59]

Originally Posted by low79fx

Isn't the wheel track width for 73 and later models 1 1/2" wider on the rearend as compared to the 72 and earlier. If thats the case wouldn't the wheel track on the front end rolling gear be the same on the later models.Would there be any way to shim the crossmember assembly 3/4" towards the driver side to get it centered? Maybe IDK?

Yes, it is a bit wider and the pass side looks correct for the late model setup. The drivers side still looks like the stock suspension in relation to wheel location to fender. LOL, IDK either, this has me stumped big time.

We also measured from the center of the water pump shaft to the inside top lip of the fender on both sides. They were within a 1/16". So the fenders in relation to the center line of the engine/drivetrain are spot on prefect. So, this tells me it has to be in the suspension but where? LOL. The donor suspension truck appeared to be in excellent condition and no signs that it had ever been wrecked. We spent quite a while looking before we chose the one we did because the truck was so clean and mostly still complete.

The ONLY mod we did was cut one coil off the springs. Everything else is bone stock original, only rebuilt.

[markeb01]

Since you seem to be eliminating potential problem areas, I’d go back to the beginning and try a different method to measure the cab for square over the entire length of the chassis (which it sounds like you have already done). Perhaps check the cab diagonally across the opposite ends of the frame.

This turned out to be a problem on my truck. I don’t have a frame jig to compare my truck against a perfect baseline, but I had to “turn” the cab on the chassis to get the front end sheet metal to square up, and this also corrected a factory misalignment between the bed and the cab which always had a bigger gap on one side than the other. There’s a lot of adjustability available in the cab mounts. I hope it’s not the frame.

I just finished re-reading the previous entry again. In addition to measuring from the center of the water pump to the fenders, how about measuring from the water pump shaft to the frame. It’s possible the engine is not centered in the chassis and this confusing the issue?

[jonzcustomshop]

I thought engines always sat a tad bit to the right, when I built my model t hot rod, I set the engine perfectly centered in the frame rails, it had a real short drive shaft, and the rear end I used was off center to the right just a little bit, it drove me nuts for a bit measuring from the backing plates to the frame....then I checked out a few cars, and noticed the offset

how is the measurement from the center of the radiator support to the corner of the a arm, or backing plate?

[tincan1966]

Couple things come to mind here- and just guessing, but did you double check the backspacing on the wheels or try switching from left to right to see if it changed anything? Also, are your rotors the same- there are HD and STD and they are different thickness, also the bearings races are in different locations.
Just a thought, but can't see adjusting the cab over and over if the front clip is square to the frame. There is no way to shim the crossmember side to side.
Something you MAY try is to cross measure the control arm shaft centers - measure from the left upper shaft center to the lower right shaft center and the right upper to the left lower. the measurement should be nearly the same + or - 1/16". This will tell you if the crossmember is square.

Also curious, how was a 4 wheel alignment performed on a truck with live axle rear suspension and without the body?

[CVA59]

Originally Posted by tincan1966

Also curious, how was a 4 wheel alignment performed on a truck with live axle rear suspension and without the body?

When you have an adjustable rear end as well as front end a 4 wheel alignment is accomplished by setting the front end to factory specs. With a pod on each wheel you can then adjust the rear end as needed. This has no affect on the body of the vehicle. There are also a couple other ways to setup a 4 wheel alignment but as a former alignment tech this is how i always did it.

Thanks everyone. I will go back over it and measure everything i can think of. Hopefully i will be able to narrow something down today.


Not to get off topic here but does anyone have a "small" heater delete plate they would part with? I have the one that goes up on the firewall cowl area. I need the one for the firewall itself.
Thanks,

[CVA59]

I have been thinking about this allday. Do you guys with SBC using short valve covers ever have a problem with the pass valve cover hitting the firewall?

I also noticed that my original steering shaft is lined up perfectly with the late model steering sector and it should not be. I spaced the sector away from the frame 3/4" -1". So this is starting to tell me with the pass valve cover hitting the firewall and the steering shaft lining up when it shouldn't, the cab possibly needs to side shift to the pass side about an inch. This is the only possible explanation i can come up with so far.

[markeb01]

The 350 in my 1960 is pretty much centered in the firewall cavity.

[CVA59]

mine is offset to the pass side which may explain the problem. What do you think?

[padresag]

Originally Posted by CVA59

Not to get off topic here but does anyone have a "small" heater delete plate they would part with? I have the one that goes up on the firewall cowl area. I need the one for the firewall itself.
Thanks,

think A.T.Rockdriller was saying the other day that he did
ron

[padresag]

the firewall cavity may not be exactly centred either
ron

[CVA59]

I went over today, loosened all the cab bolts. We moved the cab as far to teh right as it would go. This closed the gap from a little over an inch to 5/16". So this drastically improved this situation. Enough so that i can live with 5/16". I still don't understand why it is out but i can live with now anyway. Thanks for the help.l

[RockTonka]

We've got one of the small heater delete plates that you're looking for...PM sent.

[erock805]

if ur suspension is square...(measured in criss cross from back to front..then it has to be the body. Engines arent always center so not a good point to measure. One of my trucks was about 5/8" off to the left. Only way you coud tell was the front bumper gap was off. You are doing the right thing with the cab. Also I never had any clearance issues with the valve covers on any of my trucks. Ol trucks wont be perfect, but you can get em close...