Packard Forum Index » Post-War (1946-54)

I have a 1951 300 and I never messed with the trans or driveshaft yet. I have some play in the front of the driveshaft I was wondering if that's normal or if I have to change the ball-trunnion joint?

I always take down the drive shaft, disassemble it and clean it very well. Then I repack it taking care not to overpack as manual warns. I have been fortunate so far. The Detroit Senior unit is very difficult to come by. The Junior unit is available from NAPA.

Is the play in the driveshaft normal or is that a sign of wear? Do I use bearing grease or something else? I see the manual says don't over grease but how much is too much? Sorry about all the questions I never delt with a ball trunnion joint before and the manual isn't that specific on packing it.

I don't know what others do, I use No. 2 Heavy Fibre universal joint grease specific for ball & trunnion joints. I suspect that it's NLA but fortunately I have a good supply from a Mopar years ago with the same type of joint. I use about 1/2 cup of grease to repack it after cleaning. I suspect one of the modern wheel bearing greases like Pennzoil 707L or Mobil XHP 222 would be just fine.

As far as play, I'll let others with more experience comment on that, but in my own experience when they get worn excessively they get noisy - kind of a machine-gun chatter on fast acceleration or very rapid deceleration. And don't confuse rotational play in the shaft with free play in the differential/axles.

Others will have far better advice, I'm sure.

Thanks for the help. After I pulled a part the driveshaft I see the movement was normal and the grease looked somewhat fresh yet I added a little. I too have that "machine gun chatter" when I accelerate along with the hard knock when it shifts. I think I've fixed the problem I bought a set of Add-a-leaf spring helpers they are short maybe 15" heavy arched leafs you bolt on without removing or modifing anything. The springs add another 1500lbs of strength and are about $30 at the auto parts store. I installed them, took the packard out, and no more machine gun acceleration or hard shifting. So I think my problem was weak leaf springs causing axle wrap under high torque.

Check the spring shackels to see if they are worn or seized.

Also check the center bolt of the leaf springs. In some cases the center bolt, that is the bolt that the axle centers over, somewhere about centre of the spring, can be closer to one end of the spring than the other. If springs were installed backwards at one time then the pitch of the differential u-joint can be changed causeing various noise problems.