My 2007 GX470 runs like a Switch watch as always, but i have lately noticed a noise when in motion. It sounds like tire or road noise. It is not from the engine as it corresponds to the speed of the vehicle. Maybe it is road noise, but the rub is that i never noticed such a noise previously. The tires are in good condition. Transmission fluid appears to be full, even though it is so colorless that one can hardly observe it. I have never checked my differential fluid - that is tough to remove - but neither have i observed any leakage. I would greatly appreciate thoughts on the issue. Thanks.

Just occurred to me that i should evaluate the brakes, but i doubt that is the source.

 

Front calipers love to seize up on these trucks, I'd start there. Have someone walk beside the truck and pinpoint which corner the noise is coming from, and go from there.

 

We'll give it a shot, but if it was brakes i should feel a fault when i apply them as they would be unbalanced when applied. It really sounds like tire noise but i don't see why such would suddenly occur. It's a head-scratcher.

Thanks for your help.

 

My calipers seized twice and the only reason I knew was because of too much play in the pedal.

 

I suspect one front caliper is bad, but I am having one hell of a time trying to get the wheel off. Yes, i removed the 6 lug nuts, but that thing is really on there. Wonder if it is related to an overheated caliper?
Any thoughts would be much appreciated.

 

Most of the time a good mule kick or seated kick to the tire's sidewall (flat foot, try not to hit the wheel) would knock it loose, but a couple times I've had to set the lugnuts snug then back them off a turn or so, and drive back and forth on the driveway until it lets go. That last one has never failed.

More likely just road grime or galvanic corrosion due to dissimilar metals. Brakes would make that area high heat anyways. Clean the back of the wheel and rotor mounting surfaces really well, and put a smear of anti-seize on the rotor surface, and it shouldn't be problem again.

 

I used a website called JustAnswer and for $26 I had a conversation with an excellent mechanic from Texas. Sprayed it with WD-40 but no kicks or hammer blows on the rubber would dislodge it. So he told me to use a pry bar against the ball joint, which I would never have touched without his advice, and it popped off. Well worth the price in terms of saving me aggravation. Highly recommend it.

He also recommended the use of anti=size lubricant to prevent such problem in the future. You can be sure that I will use plenty in future.

Finally got in there and the brakes look great with the exception of a broken anti-rattle pin that was broken and rubbing against the rotor. I believe I have found the problem but I can't be sure until I complete the job. It does seem likely that the broken spring was the source of the mystery noise. I am hopeful that I can get out of this with a $4 hardware set rather than expensive brake parts. We'll see.