Originally Posted by Fox
I watched my odometer and noticed that it read true to a mile. Very strange/fortunate that it did so. I suspect the sm420 I got from a later donor truck may have been geared for a 4.10. The speed felt very accurate as well.

Ok Fox– With the new gears, what was a comfortable speed? I have a 4.10 chunk out of a 68ish Gmc so I will definitely be doing the swap. Just curious what I should expect. A short jaunt up to 60 once seemed overly abusive...

1951 GMC 250 Open Express
1968 C10 Suburban
1971 C20 Pickup

My Dad told me "Son, never hit a man in anger- unless you're certain you can get away with it"