Goof if you told us what model your truck is I missed it. Since the rear gears and empty weight vary with model it does make quite a bit of difference.

But regardless, an old babbit pounder isn't going to go real fast very long...

1955 1st GMC Suburban | 1954 GMC 250 trailer puller project | 1954 GMC 250 Hydra-Matic | 1954 Chevy 3100 . 1947 Chevy COE | and more...
It's true. I really don't do anything but browse the Internet looking for trouble...