hello everyone, new to the forum... I've got a 97 Toyota Tacoma 4X4 extended cab with a V6... only when I lock it in 4X4 do I hear a horrible grinding noise... I can jack up the front end and lock in the hubs and the front turns and sounds fine... spins freely and no noise... its only when I lock it in... the reason I think its the pinion bearing is if I lock the hubs in or out it grinds... only when I lock the transfer case in is when it does it and it pulls on the front driveshaft... I can drive down the road with the front hubs locked without the transfer case locked and no noise... I'm wondering if its the pinion bearing going out on the front and it gets in a bind when I lock it in? Or if its the transfer case? any help would be appreciated!

 

im having the same problem with my 86 runner, when the hubs are locked and in 4 it grinds , but only if im going around 30 in 2nd, ... its weird. and im new to this.

 

Did you ever figure out what was making the noise? I have an 87 4runner that in 4wd it will make a horrible grinding sound when my foots on the gas trying to get out of the snow or dirt. I think it's coming from the passenger side so I pulled my hub and the bearing has a little bit of movement and the wheel bearing is a little worn on that side. Could this be it?

 

it was the same on mine, the worn bearing wasnt helping, but it wasnt my problem. it was the brass bushing (farther inside) that was worn out and the spindle was rattling around/ grinding as the wheels spun. like an old lady vigorously stirring her tea.

 

check out this thread...

https://www.yotatech.com/forums/f116...ctures-100327/

I dunno if it applies to 4th gens but I was getting a very similar noise, extreme grinding, vibrational noise, would start and stop randomly, but was VERY noticable. Didn't seem to affect the driving much but was so loud it was barely drivable.

Flanged up one of those spindle lubricators and greased it up, never had the problem again. Mad props to toyota mdt tech, guys a champ.