The Stovebolt Site Forums The Shop Area Driveline Tranny won't go into reverse (SM420?)

Just in case you get an urge to replace the crash box with a SM420 you'll find it to be longer than the crash box, more than can be taken up with the drive shaft. I tried putting a crash box into a 48 half ton and couldn't do it. I wanted to replace a tired three speed and SM420s in those days were still in current production so I couldn't afford it.