I'm thinking mine might be a problem with either the transfer case or the ADD not fully functioning. Like I am half-way in 4WD and some component is making noise in the wrong position.

Does your 4wd engage and disengage properly?

 

It seems to. Light comes on anyway. Haven't really tried 4wd

 

The front shaft generally spins with the truck on stands while in 2WD and in D. It will stop if you grab it.

Normal.

A bad rear bearing will send its noises to other drivetrain components.



Andreas

 

aowRS is that with the engine on? I am heading to harbor freight tomorrow to buy a floor jack and stands. It sounds like I should lift the front end, start the engine, put it in drive, and see if the driveshaft spins, and grab it to see if I can stop it?

I saw that your noise issue ended up being the rear wheel bearing, so if after I get my stethoscope and troubleshoot my 4wd, that will be the next place I look in earnest.

 

I have no noise when in 2wd on stands. But when going down the highway, doesn't make any difference if in 2wd or 4wd, I have the noise.

 

sawguy,
I wish you lived closer, as I'd love to help narrow this down for you.



Andreas

 

sawguy,
Any update?



Andreas

 

Yea thanks for the follow up.

With the front lifted, and putting it in 4wd, the driveshaft would not rotate, but the tires would spin freely. In 2wd, the driveshaft spun independently, and the front tires locked together so when one was turned, the other spun the opposite way.

I was really confused by this, and started to think that the vacuum lines on the ADD got turned around by the old owner. So I switched them up at the sensors in the engine bay. Then everything worked for the 4wd. It would engage and the light would stay on, and it would disengage and the light would go off. So 4wd fixed! And i was right to think I was halfway in 4wd all the time.

But the clunking problem has persisted on its own...

In 4wd the clunking is distinctly louder, and I would not take it past 20mph. In 2wd it is a clunking under 10mph, and then turns to a shaking of the rig at highway speeds.

The previous owner said he had a new differential put in the rig by his (backyard) mechanic. Since it is a Limited, I wonder if the put an SR5 diff in. It would be geared to 4.10, while the Limited back would be 4.30. I think I am right with that. So I think I have a chipped tooth in my front diff.

I haven't pulled it yet because I can still get back and forth to the hardware store, and my house has some pressing projects currently.

Just realized that you were probably talking to sawguy, but there's my update for you if you care haha.

 

Brad,
Good investigative work - curious to see what you find with respect to the gearing. Where are you located?



Andreas

 

Andreas,

I am in Branson, MO

 

No..sad to say. I've just been driving it with the howl. It's getting a lot louder now at 40 mph. Has to be a bearing of some sort. Still sounds like it's up front. Been putting off doing any work on it because of something going on with my hands. Wrists hurt and not much strength in hands. See the Dr. in the morning.

 

Best of luck getting your hand issue sorted - more important than the truck..



Andreas

 

Belated update... I finally found out what it is. My tires!!! Unbelievable you can hear the noise even on a gravel road. Cooper ATP's. The fronts are cupping. I don't know now if it's related to my truck or tire defect. I have no steering wheel shimmy or shaking at any speed. Does not pull either.