2nd Gen Non-Engine/Transmission wobble (?) noise

[Tractorat]

Been trying to figure out this noise for a long time. Sounds like kind of a wobble. I hear it only when moving. From both driver and passenger seats it sounds like it is coming from maybe just the other side of the firewall (?), maybe toward the middle of the truck (?).

Ive found that if I push the gear shift up toward the windshield, I can soften it if not eliminate it. But I have to keep doing that. The sound does not go away if I put it in neutral and coast. Ive even shut the engine down (at low speed) and the sound doesnt go away. It stops when the truck stops.

I did crawl under the truck and sprayed the trans linkage with silicone spray, but it made no difference.

Any ideas ?

 

[KATOOM]

Is this a noise which follows the engine speed or does it follow the road speed and the drivetrain?

 

[Tractorat]

Just road speed. Goes away when Im stopped. It is still there if I put it in neutral and just coast. I dont think it seems to be any faster with faster speed. I used to think it was in the gear shift linkage, but I dont think so anymore.

 

[KATOOM]

Does it sound mechanical and metal or softer and rubbery? How fast is the pitch? Harmonic and faster like drivetrain or slower like tires.

 

[Tractorat]

Does not sound like drive train or tires. I would not say it has a rubbery sound. It has actually changed over time, but it is definitely the same culprit. Sounds almost hollow. Listening from both the drivers side and passenger side, it sounds like it comes from the center, maybe just the other side of the firewall.

 

[KATOOM]

Hmmm..... I'd suggest parking the truck with the e-brake on and in neutral. Climb under there and push, pull, tug, shake, etc..... the driveshafts and the transmission/transfer case looking for ANY out of ordinary movement or play. Common things to look for is a worn out double cardan joint on the front driveshaft and making sure the transmission and transfer case are all secure to each other and the engine.

 

[Tractorat]

This truck just hasnt had a lot of 4wd driving in its life. But I hadnt thought about looking at the front u joints though. Ill take a look. Thanks for the suggestion. (btw, the noise doesnt change when I am in 4wd, forgot to mention that)

 

[KATOOM]

It probably wouldn't change much if at all because you have an '02 and most '02's have the non-CAD front axle which means the 4wd system is full time. That means the front driveshaft spins all the time whether you're in 4wd or 2wd. This generally isnt a problem unless the truck has been lifted but it does cause the front driveshaft u-joints and double cardan joints to wear out faster since the angle is usually steeper than the rear driveshaft.

 

[Tractorat]

Thanks again. I will definitely take a look at that. Im probably going to have the track bar replaced some time in the next few weeks. Im going to have them take a look as well.

 

[Tractorat]

But that still doesnt explain why, when Im in drive, I can stop the noise by pushing the gearshift up toward the windshiel (still in drive)...

 

[KATOOM]

Maybe just simple noise transfer.....

 

[JMcCoy]

This one sounds tricky. Might not hurt to take a look at the carrier bearing. Have you checked you transfer case fluid?