2nd Gen Non-Engine/Transmission Driveline Thump

[MBFARMS]

When I take off and easy into the throttle I get this like kinda bump in the driveline. It kinda feels like when you let off the thottle real quick and get back in it real quick. I think you call it gear lash, but that is the what I am feeling. I have searched the axle wrap threads and I get no shudder so I don't think it is axle wrap. Any ideas?

 

[Joe Mc]

I had a Toyota that had a dry slip yoke and everytime I'd take off easy when it would shift from 1 - 2 if would "bump" the whole driveline. I just noticed you have a 6 spd - check trans mount.

 

[MBFARMS]

Thanks for the reply I will check that out this weekend.

 

[Beast2B]

check the u-joints and flange bolts, too. lay under the truck on level ground in first gear with the parking brake off. i used a couple sticks of firewood about a foot in front of and behind the tire for chock blocks. have SOMEONE YOU TRUST stand on the rear tire and hold the bed rail. when they roll the tire back and forth you might find some slop.

BE CAREFUL!!!

 

[Joe Mc]

MB did you figure it out yet? I forgot to mention the "dry slip yoke" was dry for so long it it created a burr insed the female end and had to be replaced. Unfortunately I didn't see a grease fitting on our trucks - gotta love mother Dodge, she took all that money saved on the tons of zerk fittings not used and put it into R & D on the 3rd Gens - "Yea RIGHT!"

 

[MBFARMS]

I haven't found it yet, going to put it on the rack this week and really check it out. This only happens when taking off and then excelerating.

 

[Joe Mc]

If it is a real heavy "thud" that only happens when taking off and accelerating, unlike a light "thunk" that happens periodically I'd still take a hard look at the mounts, leaf spring bushings and maybe even the shaft center carrier bearing (not sure if short bed has one piece or not).

Please do keep us posted this has become a "foster child" of mine.

 

[MBFARMS]

The drive shaft on a SWB is one peice, no midshaft bearing. I have looked the truck over and looking hard at the u-joint and the plastic peices in between the springs, they are slap wore out. Thinking this will fix the problem. Will order parts this week and see.

 

[MBFARMS]

Ok, finally got the problem solved. The plastic glider pads that are in between the springs was the problem. When I went to take off the springs were flexing and with on surface to glide on it allowed the springs to kinda pop or thump. I have done some really heavy towing over the life of this truck and I guess that contributed to the wear of these pads. When I put the new pads back in I sprayed plastic safe lube on them. I will be spraying these things with lube from time to time to ensure better wear.