Driveline slop?

[Exile]

I’ve driven a few trucks, and most of them, well, they were “experienced” (kinda junk)

 Where does the driveline slop come from?  I mean that if you stop going down a slight incline, there will be a jerk when i let out the clutch as the driveline turns before the wheels turn,

does this happen in new, or properly adjusted drivelines?

seems lite it could come from xmission, ujoints, and two diffs,  my ujoints are tight, should the diffs be tight?  Or have slack in them?

 

[Jaydrvr]

Of course, every truck had different wear points, but often in my experience, the slop is caused by worn out springs in the clutch plate. They are designed to soften the clutch engagement and protect the driveline. If they're dead, the engagement is pretty harsh. Jay

[Deezl Smoke]

 I think you already have some great insight as you mentioned the drive line rotates before the wheels. This is the rear axle(s) gearhead(s)  There are a few points of wear within the gearhead. The pinion to ring gear lash. The spider gears on their pins and the spider gears to side gear wear. And then the axle shaft spine wear. Ad to that in a tandem configuration, you'll have the interaxle differential and the mechanisms that go with it like the reverse rotation pinion drive gears in the front gearhead, the interaxle diff itself,and the drive line between the two axles that is at a very steep angle and wears much faster than the rest of the drive line.

 However, in a long wheelbase rig, if a carrier bearing holder is worn out it too can ad to that feeling you have in the cab going from power to compression braking. Transmissions can have some lash as well. But generally, IMO, that lash will correlate to how much noise it makes through the stick.😮

Edit to ad. Even in a brand new rig, there will be some lash. But naturally they will gain lash as they gather "experience".🧐

Edited March 7, 2020 by Deezl Smoke

[Scrap]

Add rear engine mounts and bellhousing bolt torque to the checking list.  Also check rear susp rebound bumper and spring eye parts if it is the Peterbilt.

4-bag trucks on a hill I'll either limo stop it or let off the brakes for a sec so it isn't all bound up when trying to go again.

[Exile]

3 hours ago, Scrap said:

Add rear engine mounts and bellhousing bolt torque to the checking list.  Also check rear susp rebound bumper and spring eye parts if it is the Peterbilt.

4-bag trucks on a hill I'll either limo stop it or let off the brakes for a sec so it isn't all bound up when trying to go again.

Thanks,

Spring eyes good, i believe there is space at the rebound bumper or wear pad, but I usually see it deflated.  (Air trac)

Looking at it, there is a 1” gap, i see aftermarket companies sell a poly wear pad to cushion the blow.  With that, it seems like that should only come off the wear pad if i were to break hard  but, empty, it might take less torque.

will crawl through and check the engine and clutch end of the truck

Ujoints tight by hand,

since the driveline will rotate about ten degrees, i assume it is all additive slop in the rear ends.

 

[noteven]

Scrap I see you found a shift pattern placard for a cab over with 18spd u shift complete with 2 million miles:)