Yesterday we drove home from Georgetown, Colorado to Skiatook. When we first took off we experienced a weird noise from somewhere ahead of the driver that sounded kind of like something was dragging. It did it several times, and a couple of times when it ended we felt a "thud" in the truck like something was rolling around and hit something. But, after a few miles it quit doing it.

I wasn't worried as the truck has done this several times before, and always during the first few minutes of a drive, and only then briefly. However, about 400 miles later it did it again and for at least 30 miles, although it varied in intensity several times. We shot three videos of it, and there's a link to the best of them below.

Now for some specifics:

• We were on cruise at 75 MPH and on I-135 just south of Salina, Kansas which is a good road with little road noise.
• The sound seems to be just ahead of the driver
• Turning the HVAC system off made no difference
• Turning the entertainment system off made no difference
• Raising, lowering, or tilting the steering wheel made the noise either pause or go away while the movement was taking place, but it came back as soon as the movement stopped
• Taking it off cruise stopped the noise abruptly and it never came back, even though we used cruise for another 250 miles after that. But, I should add that we weren't on cruise when the noise happened at startup, nor were we on cruise when it had happened before.

I need to take the truck in for the guys to look at it, but it happens so infrequently that I really doubt they can recreate it.

Anyone else have a similar noise? Any guesses on what it might be?

 

Gary, the noise sounds like a puffing or gurgling noise to me rather than anything which is in rhythm with what I would think would be engine speed. Is there anything exhaust related [EGR, turbo blow off valve, etc.] in that area which might be affected by the movement of the steering wheel or near the cruise control mechanism?

 

David - Forgot to send you the link. Glad you found it. And, you have good points, as always. I forced a downshift and got no change in the noise, and changing speed made no difference either.

As for turbo or exhaust things, I don't know. Am I allowed to look under the hood on these things?

 

Could the sound be coming from the duct work on the driver's side?

 

You must do it while cruising at 75 MPH Gary.

 

David - I don't know if it is from the ducts, but I do know that turning the HVAC off made no difference, nor did raising or lowering the fan speed.

GG - Good idea! I'll drive and you look?

 

You sure it isn't your IWE's going bad?

Josh

 

Sounds like the IWE. Just had mine replaced. Does seem to start when coming to a stop and happen randomly?

 

What is an IWE?

 

Integrated Wheels Ends aka the locking hubs on the front axles.

They make a weird grinding noise when they go out. Usually at slow speeds though, but I have seen the videos at high speed too

Josh

 

Yep, just found a post that explained that. But thanks. That may well be it as we were up in CO on wet dirt/gravel roads and some snow, so I used 4A several times and 4Lo for the very first time. (Even locked the rear diff - to no avail. On what I refer to as "snice", meaning snow-turned-to-ice, there is no traction, so 3 or even 4 times 0.0 is still 0.0.)

But it hasn't happened when stopping. Instead, it has almost always been when starting, and especially after an overnight stop. But, in the case where it went on for 30 miles it started after we got on the highway again after a 30 minute stop during the 700 mile trip.

This may explain the thunk we felt yesterday, which would be when it finally engaged. But, why would it be engaging at 75 MPH when I had it in 2wd?

 

The IWE's can fill with water and the vacuum isn't enough to disengage them. Default is engaged.

The solenoid can fail too, but it seems to me the IWE fail before the solenoid does.

Easy check is next time to switch to 4H while driving and see if the noise stops.

For whatever reason my IWE's were acting up when I went to Grand Teton in March. Could hear them grinding as I cruised thru the motel parking lot first thing in the morning. Hasn't done it since though. I verified my solenoid works, no vacuum leak on any of the lines and the IWE's disengage with the front wheels off the ground and engine idle.

Josh

 

From what I read here, it takes vacuum to keep the hubs from locking. And, if there's a vacuum leak the hubs try to engage at any time while going down the road.

Ok, it is all sorta fitting together. The sound sometimes happens and then we get a thunk, which presumably means it has engaged. However, it should not have been trying to engage, so there's a problem somewhere. And, the fact that it tried to engage for 30 miles suggests the splines may be in poor shape by now.

 

Theoretically, the IWE should wear out before the CV axle splines do.

Josh

 

When I talk to the dealership tomorrow I'll suggest that it is an IWE problem. It really fits the symptoms, and nothing else seems to do so. Thanks!