The Stovebolt Site Forums The Shop Area General Truck Talk measure frame

I've taken front fenders, grille and radiator support off the '57. I tried to check the frame for square and shows to be off by 5/16". But, finding good points to measure from are difficult with the cab on. I'm not finding anything to measure from close to the cab. I'm not planning on taking it off at this point of this project. 5/16" from a side hole close to the cab to center of the front front end rivet seems like a lot. The truck drove straight before the tear down. Where would you go from here??

57Chev,

Unless you are mounting some new suspension component, or had tracking or wandering or tire wear issues, I would consider the case closed. I know it's fun to check these things, but if you hunt for a problem that doesn't exist, you end up loosing sleep or getting constipated!

Stuart

If you take the cab off then take measurements. If you don't take it off it won't make any difference anyway cause you won't be able to make corrections.

To check the frame for square.

Choose a level, smooth surface to work on. A garage floor will work well, even though most slope.

Support the truck frame by jack stands with the frame as level as possible. It does not have to be perfect, just close at this point.

Find a factory hole at each end of the frame and the corresponding hole on the opposite side. They should be as close to the end as possible. These will be your reference points.

Drop a plumb bob from each hole and mark the floor. You should find that the points on the floor are the same distance apart from front to back and from side to side (if I remember correctly the 57 frame rails are parallel). It is also a good idea to drop the plumb bob at a mid-point on the frame to check for rail straightness.

Now measure the points on the floor, corner to corner. This will give you an idea how much your frame is out of square. Remember that the out of squareness is 1/2 of difference between the long dimension and the short dimension. In your example above, 5/16 longer one way would be out of square 5/32.

Make sure you are checking spots that should measure square. If the hole or rivet you are using to measure against was not placed square with the other originally it may not mean anything that its not square today.

Thanks all. Was looking mostly for methodology. Thank you, Lonnie and all.