My 1949 3600 shudders or chatters real bad when letting out the clutch. It's much worse when cold and/or on a hill, especially in reverse. Once the truck has been run for a few miles the forward gears are OK. I went in to r&r the clutch but found that the intermediate driveshaft bracket was completely missing the carrier bearing rubber cushion. There was an inch of play in the driveshaft carrier bearing support bracket so I figured that I had found the problem. Since the problem is much worse in reverse I'm starting to wonder if the brakes are grabbing. Once I tried reverse and forgot to let out the e-brake and found that the problem felt exactly the same. Any thoughts? I'm going to go through the brakes next week. I only bought the truck a couple months ago and the brake lines, cables, brackets, and inside the hubs are all new. I have not seen inside the hubs yet; just going on what the seller told me. All of the other brake parts are noticeably new.

http://www.leonmack.com/
'48 Chevy 1/2 ton
'66 Volvo 122S 2-door
'68 Volvo 220