2nd Gen Non-Engine/Transmission Driveshaft bearing

[kenny61]

If you grab the driveshaft and shake it should it move in the rubber? How much?

 

[B.G. Smith]

I would say you might be able to flex the rubber a small amount but there should be no free travel of the shaft inside the rubber. The bearing is bonded to the rubber part of the support. bg

 

[kenny61]

Its the rubber thats flexing but it seems a little too loose for me

 

[fest3er]

As I recall from my F150 (12+ years ago), the rubber should be snug inside the outer shell. If it's loose, it can lead to vibration in the center support bearing (CSB).

If the driveshaft slip joint doesn't (that is, it binds), it can push the CSB out of place, causing vibration and noise.

I went through 2-3 CSB on my F150 until I figured out the slip joint wasn't. Fixed that, and the CSBs stopped failing.

 

[kenny61]

I got a few minutes today and crawled back under the truck. The bearing is definetely worn, the center u joint has a little play and the pinion seal is leaking So I will be changing all of them out. Now I have another question how much play (twist) should the pinion have when you turn it? I can twist it back and forth and the movement is noticeable, a couple of degrees maybe, how much is too much and how do i fix it?

 

[B.G. Smith]

The movement you feel turning the pinion is probably normal. If there is no radial play in the pinion and you are not hearing any gear noise whilde driving then it's probably fine. The movement you describe is called gear backlash and total movement is probably . 006 to . 010 of an inch. bg

 

[kenny61]

Thanks. I gotta shake it back and forth and up and down tomorrow... . Then I'll go out to the truck and check the pinion



So a little rotational play is ok but no side to side / up and down?

 

[B.G. Smith]

Thanks. I gotta shake it back and forth and up and down tomorrow... . Then I'll go out to the truck and check the pinion



So a little rotational play is ok but no side to side / up and down?

Yep, the bearings on the pinion shaft are slightly preloaded, (face to face tapered roller bearings) you really shouldn't see any radial runout. bg