I have a 1997 4Runner 4x4 with 250k miles on it. and now when I let off the gas it makes a whirring sound or humming sound till I give it more gas.

Pretty sure that with this sound the third is bad.

The truck model is VZN185L-GKPGKA the A/TM is A03A/A340F from my understanding this is 4.10 gear ratio with 2 pinions. The Label also says P225/75/R15 although on my tires they are 265/70/R16 this confuses me.

My question is can I take an Axle Rear end Assembly from like car-parts.com and just replace the whole rear end? And also what I have no is a non diff lock can I replace it with one that is a diff lock?

Thanks in advance.

 

I bet the pinion is a little loose with those symptoms you mentioned. You might be able to get rid of that noise by tightening the big pinion nut up some. Do you see some gear oil seepage from the pinion flange?

edit---------- A03A is your rear 3rd code. I don't know what it is at this moment but you should be able to drop another similar one in yourself.

 

I tried tightening up the Pinion nut and it reduced the noise a little bit but I dont want to overtighten and ruin something else.

From what I have seen I can get a whole backend (used of course) for the price of a third.

 

You checked the fluid i assume?

 

Yeah the fluid was fine. It was leaking so while replaceing the U joint I replaced the Pinion Seal and topped off the fluid. I think I broke it when putting it back together.