Prerunner 4x4 conversion

My 99 3rz 4wd ext cab came with 430s. So maybe hunt that combo... also, I'm ***pretty sure*** that the tooth count on 430 is 43 ring gear teeth, and 10 pinion teeth. So, you can pull the drain plug out of the front diff and count the ring gear teeth. 410 has 41. 100% sure on that.

 

Ha. I never thought of counting from the drain plug. That would save the hassle of taking the clamshell apart.

Still a good idea anyway to see what condition the ring and pinion are in, and if the bearings are in good health. It’s really not that hard to do.

 

I’m starting to think 4.30 front ratio was only available 1998-2000 because I can’t find it for other years.

 

On a recent trip to the dealership I asked them about it and they were able to pull this up and said I have one of these two options but they couldnt tell me which.

 

I believe 4.56 from the factory are super rare. I would guess you have 4.10.. but the only way to know for sure is pull the diff and count the teeth.

 

Well that don’t make any sense. They’re saying you have either 4.10 or 4.56 which doesn’t correspond to B07A.

4.56 is even rarer than 4.30.

If you want to know what your rear ratio is, you have to rotate the tire a certain amount of times and count how many times the driveshaft spins. I don’t remember the math but that’s how you do it. It’s an open diff so you have to wedge one tire to the ground.

 

I’d be very surprised if it was 4.10, because I have his same gear code and it’s 4.30. I have a 1998 he has a 2000.

 

I was just saying that of the two (4.10 & 4.56) I would bet its 4.10. I've never actually seen a factory 4.56 gear set. I believe it was a special order deal... but I'm not 100% sure on that...

 

Yea I will give that a shot tomorrow, can you have the front diff re geared and matched to the rear?

 

Regearing is very very expensive. It’s cheaper to change the rear 3rd member to match your front.

 

I don’t remember the math on how to calculate the ratio off spinning the tire either. Maybe someone else can chime in. I think if you spin the tire 10 times, the driveshaft should spin 4.3 times for 4.30. Don’t quote me on that.

Keep in mind 4.1 rotations is very close to 4.3 rotations. That’s why I don’t like that method.

 

That may be an option for me as I would like to add a locker down the road.

 

If you're paying to regear, I'd regear to 4.88. That's my personal preference though with my supercharger, 3RZ, and bigger tires.

I got a quote to regear to 4.88 with rear locker. With labor and parts it's close to $4,000. The Rear ARB locker and compressor setup is $1,500 by itself. That's not including installation, that's if I installed it all by myself. Labor is for actually swapping the gears.

 

Maybe its not an option for me haha at least not for a while.

 

I'm fairly certain you have 4.30, and TIS is wrong. But I could be wrong too.

4.30 front diffs were more common in 3rd Gen 4Runners. I'm not sure what the gear code would be, as I just bought mine as a gamble not knowing if it was 4.30 or 4.10.

 

If I have time tomorrow I will give the spin test a shot. In the mean time I have this project to keep me busy

 

Daaamn, is that an FJ40?

 

yep a 69 completely origional

 

What's going on with the 3.4l?

 

Its a 2.7l scored cylinder wont pass smog, gonna rebuild it.