Bought the ‘99 4Runner with 320k miles, so I knew it was going to need some work. After a ToyTec/SuperFlex lift w/ 5100’s, I started to get a lot of stability issues. New SPC UCA, new poly bushings (upper & lower on front, rear, & panhard bar), new steering gear bushings, used 2002 Tacoma steering gear, new CV’s, you name it and I replaced it.

I was also getting a vibration almost like a wheel out of balance and was starting to get a bearing noise. Suspected the front wheel bearing, so I replaced them. The stability problems were gone, but still had the vibration and noise.

Noise started around 25-30mph, vibration started to be noticeable around 60mph and was pronounced at 80. Heaving braking caused a vibration like a warped rotor, but since I had new pad & rotors (Tundra 199 upgrade) I figured it wasn’t that.

I read this thread, checked the Driver CV, and sure enough had a lot of play at the diff.

The video made sense with what I was experiencing, so I ordered the parts & puller and replaced the bearing with the bushing.

I’d say easy as that, but it was a bit of work!

Thanks! Your description of the noises sound a lot like what I have (though I can't remember the last time I had her up to 80 ) - will check the noise in 4WD. I don't have any stability issues as far as I know.

I'm running 4600s with OME 880s. As part of a major overhaul when I bought the car, the front bearings, ball joints, inner and outer tie rod ends, rack bushes, anti-roll bar bushes, discs and pads have all been replaced. I'm running newly bought and balanced BFG KO2s.

A friend is coming over here from the US next weekend with my new bush and tool

EO

Sorry to drag up an old thread but I'm on a wild goose chase....
Getting a strange vibration in the gas pedal/floor board between ~20-40 mph when accelerating. I lifted the front slightly with 5100s to level out the truck after deleting Xreas about 5 months ago.
Could this be the needle bearing? I have 235K and I wouldn't be surprised if I'm still on the original. I read somewhere in my search for a solution that the ECGS doesn't work on the V8 AWD Limited (which I have). If this is true, and it's the culprit, will I simply need to replace the needle bearing more often?
I cleaned the throttle body this afternoon and noticed an improvement in throttle response but the vibration is still there...like a cell phone ringing. Next step is to replace the spark plugs and inspect the U-joints.

Pretty sure you've got a better chance of a meaningful reply in the 4th gen section.