Hi all, I have a SM420 in my 48 Chevy PU. It has stuck in 4th gear several times, and it usually requires pulling the top cover off, and tapping on the shifter forks to "unstick" the shifter. But this last time, the shifter was free when I pulled of the top cover, so I tried to move the larger main gear at the rear of the trans, and it wouldn't budge. So I carefully tapped it with a hammer, and it freed-up. and slid back by hand. I checked all the others and they all moved forward and back by hand. It is once again working...
Some back ground, I had this trans rebuilt 4 years ago in SoCal, at the cost of nearly $1000. He used many new gears and bearings, and all new synchros, but it wasn't until I drove it from San Diego to WA state pulling another truck, that I first has the sticking issue...
Any ideas to go and check so I don'y get stuck trying to drive home in 4th gear again...?
Thanks in advance, Garry K
