Hey All:

I have a 1969 F100 4X4 with a 4 speed Manual Transmission and my gear shift has a vibration in it. I am wondering if anyone has an idea what it could be. I have replaced all my U-Joints, replaced my Front Slip Yoke on the rear drive shaft, rebuilt the entire front end, new engine, new clutch and turned my flywheel, new brakes, wheel bearings, etc. About the only thing that has not been replaced is the Rear End gears, Transmission and Transfer Case. It seems to do it worse when excelerating and stops when slowing down. I can rest my hand on the shifter and it will stop the shifter from vibrating. The Truck rides good, drives good and does not affect the truck's performance in any way. I can blow down the interstate at 80+ mph with now problem (other than the gas consumption - but then good gas milage is for SISSY's). Just looking for some areas to start looking.

George

 

Sounds like a 435 box with high mileage.
The goofy design of a taper bearing and ball bearing on the same shaft so the ball bearing gets hammered then Mr. Timken walks out of his race to allow for the gear mesh to change, internal thrust clearances to get too wide as well the synchro gaps and a vibrating milk truck box. Yup I had my fill of a 435 which is suppose to be a bullet proof box but I would hammer on one hard and have to rebuild it under 2,000 miles again, still alive at over 900K miles.
The 308L ball bearing is first to go out which allows the input shaft bearing (taper) to get loose and cause a vibration in the shift lever. Replace that 7 ball with a 11 ball and it will hold up longer on the side thrust it gets as a ball bearing is designed for radial loads.
The engagment dogs will become loose with mileage and wear as well the cluster gear end clearance. Rebuild shim kit wouldn't help in my case, had to mill the bosses and make thicker thrust washers. That is why later shift levers had the shift pin suspended with O-rings to isolate noise and vibration which added a vague feeling when shifting. The cure was remove the O-rings and epoxy the shift pin solid.

.....=o&o>.....

 

I have to wonder if there is enough meat in the bearing support to put a ball bearing on the roller end, and prevent the thrust issues there. I know a ball bearing assembly can handle thrust bearing duties. Either that, or throw a roller unit in instead of the ball, and prevent the issues entirely.

 

You don't see this bearing mismatch on a ZF box, taper bearings only, all gears run on needle bearings with a low pressure oil pump within the transmission plus a external oil cooler. I'll take over build or designed vs cheap.
That 308L is a grooved bearing for a snap ring which I have never found in a taper bearing.
.....=o&o>.....

 

before you tear into the trans and transfer check for broken trans and motor mounts