Hello, New to the forum,
I've had the 55 3100 (later, second, style) for 4 yrs and have over 25k miles. Mostly original, it's great. My trouble and question comes after an upgrade to 3:38 ring/pinon, and a Muncie cast iron 4speed. That changed the drive shaft length. Now I had a vibration that would come on @ 52 mph (2300 rpm) and get worse as the speed/RPM increases. After new springs, it was worse. Took and checked angles on engine, drive shaft and pinion, it called for some spring wedges and it took most of the rumble vibration out, but not all. I found some play in the rotation of the pinion and and was concerned it might be coming out of fit. I pulled the assembly out, cleaned, and checked. All good. The play is in the spider gears, just like it was before the pinion and ring change. Outer axle bearings all good. I reassembled, and it was still there. So I put 140 wt gear oil in and it smoothed out some, enough to take a 2500 mile trip this month. Now I have the drive shaft to the shop to double check it's balance.
Under power, up a hill, or accelerating, smooth. Let off the gas on a steep hill, or up to a stop, smooth. Lower speeds, smooth. It just seems to be happening when running along at speed (2400+ RPM). Maybe I'm not supposed to go over 55?
Any one have any ideas or suggestions on where to got with this??
Many thanks, Bud Van Deusen
