Grinding sound offroad

[4wdrunner02]

Today I was offroading in mud. I was in Full Time 4WD and I was making sharp turns in some bumpy parts of the mud and I heard this grinding sound in the front. The sound was like metal grinding. I also tried a sharp turn on dry pavement and I didn't hear anything. I tried it a couple times on bumpy mud and it kept grinding but not on flattend mud. There were no rocks or anything like that. Do you think there are problems with the 4WD system?

[bulldog]

A grinding sound doesn't sound right at all. But if there was a big problem with your drivetrain it would have manifested on the pavement as well. Was it in 4WD on the pavement as well?

[4wdrunner02]

A grinding sound doesn't sound right at all. But if there was a big problem with your drivetrain it would have manifested on the pavement as well. Was it in 4WD on the pavement as well?

Yes, it was also in Full TIme 4wd. It was kinda weird that it didn't do it on pavement or even on level mud. Do you think it could have been my tires rubbing? It did sound like metal grinding though.

[bulldog]

It is really tough to diagnose over the web. The grinding can be from the mud adn tires/ or maybe even some gettng into the brake rotors/calipers. Check and see if you can see rubbing on your frame/body from the tires, might the easiest place to start. If it doesn't make wierd sounds on pavement you driveline is probably fine. If it was your CVs or diff you will hear it turning on the pavement as well.

I am sure you are familiar with the ATRAC/VSC sounds, so you would know the difference between that and other grinding. BTW what is the condition of your brake pads and shoes (if 3rd Gen). I assume it is a 3rd Gen from your screen name???

[4wdrunner02]

It is really tough to diagnose over the web. The grinding can be from the mud adn tires/ or maybe even some gettng into the brake rotors/calipers. Check and see if you can see rubbing on your frame/body from the tires, might the easiest place to start. If it doesn't make wierd sounds on pavement you driveline is probably fine. If it was your CVs or diff you will hear it turning on the pavement as well.

I am sure you are familiar with the ATRAC/VSC sounds, so you would know the difference between that and other grinding. BTW what is the condition of your brake pads and shoes (if 3rd Gen). I assume it is a 3rd Gen from your screen name???

Its an 02 4runner.. Its more like a metal to metal type grinding and I know its not my ATRAC/VSC kicking in. What do you mean when you say CVs or diff turning? My brake pads are going to need to be changed soon.

[bulldog]

It might just be your pads that are almost done.

What I mean by CV and Diff is that it will make a racket on pavement as it actually has more stress then.

You might also want to check Yotatech as they have lots of 3rd Gen guys there.

[Asolo]

Last time I heard a "grinding" kind of sound, it just turned out to be a rock that somehow got wedged in between the caliper edge and rotor...In my case it was just rocky mud.

[4wdrunner02]

I tried turning sharp in two wheel drive and it did the same thing. I've noticed that it only grinds on unlevel areas. On flat pavement it does not grind.

[bulldog]

All I can think of is that your wheels/tires must be rubbing on something then. On unlevel surfaces the suspension will flex and cause rubbing you will not experience onroad. Also check to make sure your swaybar/driveshafts are not rubbing gainst anything.

[4wdrunner02]

I read somewhere that it may be my steering stop caps. They might be worn out and fell off. I may take it to Toyota tomorrow. Don't know if I want to take it in and waste a few bucks just to tell me they can't figure it out.

[my034runner]

I read somewhere that it may be my steering stop caps. They might be worn out and fell off. I may take it to Toyota tomorrow. Don't know if I want to take it in and waste a few bucks just to tell me they can't figure it out.


In order for them to diagnose your problem, they have to first replicate it. If they can't get it to do the same thing, then yes, you will have wasted your $$. They can't fix what they can't find/hear. Just my 2 cents, I work at a Toyota store, and that's pretty much how it works. Now, if you take the service writer or a Certified Tech with you to the mud and replicate the problem, then you would have a shot. :D

[05sport4x4]

I read somewhere that it may be my steering stop caps. They might be worn out and fell off. I may take it to Toyota tomorrow. Don't know if I want to take it in and waste a few bucks just to tell me they can't figure it out.

I think you are right with the steering stops. In my pick up which is the same as a 2nd gen. the caps for the steering stops wore out a long time ago and when I would make a full lock turn on even a slightly uneven surface there would be grinding sound. It sounded pretty bad both inside and outside the truck. I finally took it to my mechanic thinking that it would be an expensive repair. When I told him about it he said it was nothing and got a finger full of grease and coated the inner and outer wheel stops on both spindles. I did not think that would have fixed it but when I tried to make the sound again it was gone. That was at least 5-6 years ago so about once a year if I remember or when the sounds reappears I plop some heavy wheel bearing grease into the pockets and all is well. I just did it 2 months ago with it last oil change.

I hope this is your problem because it is cheap and easy to fix.

[007-FJC]

I need to drag you out to the trails with my 02. What part of the world are you in? If your in NorCal, I have noproblems goin 4wheelin this weekend in Frank Reins park.

[4wdrunner02]

I'm from the Washington Area. That would be sweet to do some trail riding with people who know what they are doing.

[4wdrunner02]

Does anyone know if it is normal to hear a humming or rubbing sound in the front when you're in FULL TIME 4WD? I was driving my 02 4runner on dry pavement with Full Time 4WD and I can hear something humming or rubbing whenever I accelerate.