Well this is just about my first post and I need some advice. I just bought an 89 'Yota x-cab V6 auto. It has 250K miles with a rebuilt engine. I want to change out/rebuild my diffs for two reasons:

1. The truck has 4.10 gears with 31 inch tires and can't get out of its own way.
2. There is a whine in the rear from the diff I believe. So I either need to rebuild/swap the diff and do axle bearings.

It is my understanding that a 4cy with 31" tires would have 4.88 and a V6 auto with 31" tires would have had 4.56. Correct? I would like to get it as close to stock as I can. I love the look of the 31s and am most likely not going much bigger (if at all) than that.

I went to my local salvage yard and there are a few nice cash for clunkers 4-runners on the lot. There is one G284 4.3, and a few G144 3.0L V6 auto which would be 4.88 correct? I am confused because I didnt think the 4.88 would come in a v6 auto, just the 22r. According to the gear calc my stock 4.10 w/ 28" tires would be spinning 2248rpm @ 65mph. If I went with 4.88 w/ 31" it is 2441rpms @65mph. That doesnt seem like I am giving up much top end if I gain more acceleration.

Am I correct that they have 4.88? Should I buy and swap them if they are correct? Would it even be worth the trouble to swap in the 4.3?

EDIT: So I searched the forum as opposed to just reading the stickys. So G144 is correct for 4.88s on the 92 4 runner that would have had 31 in tires. Since I have the same 3.0l and possibly the same auto then I would think 4.88s would be perfect as I would be just stock for the 4-runner correct? Also, the front is a ADD but I can just swap my axle tube onto the 4-runner diff to eliminate it right?

Sorry for all the questions. I hate being a noob but I dont want to buy the wrong thing.


Thanks,
E

 

go with the 4.88s

 

Up until '91, the V6 with auto trannies were under-geared with 4.56's. In '92, Toyota put in the 4.88's. And this is with the 31" tire package. Go with the 4.88's

 

So it seems like the 4.88 is the consensus. That is good because in the two junk yards 10 minutes from my house there are 4 to choose from. Two of them are so clean I might get the seats as well.

 

Get the 4.88's and you can run 33" tires and have plenty of zip.
I'm running 4.56's and 33's, it's not bad but a little hard on the clutch on the hills and the added power would be helpful off-road.