I've been reading the previous posts about regearing, and it seems that 4.88's are the way to go for my vehicle. i want it to have some more torque for bigger tires, but i still want to be able to drive 70-80 mph on the interstate without reving my engine to death. also i was wondering if regearing would help or hurt my gas mileage(engine reving higher but not downshifting as much). What rpm should i expect with this gear ratio at about 75 mph. I think a lot of people on this forum have done this mod and would like some input from people with similar rigs. 3.0 v6 with manual transmission. Does regearing to 4.88's help much to make the 3.0 feel powerfull. Thanks for any help that can be offered.

 

You didn't say what size tires you want to run. 4.88s are excellent with 33s. Re-gearing is the cheapest and most effective "horsepower gain" you can make. Period, no professional will disagree. The trick is to get it back to stock as close as you can. If in doubt go a little over to comepnsate for the additional resistance that comes with taller tires and the like. (I.e. if the math says to go with 4.73, then go up to 4.88 rather than down to 4.56.) Unlike say, Chevy or Jeep, Toyotas are well engineered to run best (in it's horsepower/torque sweet spot) with the tires and gears they came with, so keeping the engine revs in that range works best.

To find your rpm, do this: Note the rpm now at 75 mph. Multiply that x 4.88, then divide by your current gear ratio. That will give you the rpm to expect. For example: I'll assume you have 4.10s. So, take 2800 rpm now, times 4.88 = 8784, divided by 4.10 = 3332. You'd expect to see 3332 rpms with 4.88s with the same tires a that same speed. But, if you have 31s now and you go to 33s, you'd go 3332 x 31 = 103292, divided by 33 = 3130 rpm. Still better than you're doing now, and bigger tires too! Gears can do what horsepower can't.

 

That is just about right. I have factory 4.88 gearing with an automatic and 31x10.5x15 tires. At 75mph I am just a little over 3k.

 

i was planning on 4.88's with 32's for now. then maybe go bigger later on. planning on doing a 3in lift this summer and putting on some bfg all terrain 32-11.50's. but dont know if i wanna wait till i regear, because she feels pretty slow to me already. i went from a 98 trans am with a six speed to my 4runner so it was a big drop for me already, and i dont want to go slower.

 

I shall re-direct you here:

https://www.yotatech.com/forums/f31/my-new-favorite-number-4-88-a-34709/

 

By way of illustration, my buddy has a TJ with 35s and 3.73 gears.... <yeah, no kiddin!> He has spent big dollars on header, exhaust system, intake, chip, and is talking about a cam now. All told has spent about 1500 bucks to gain about 20 hp, but doubtful if there's any add'l torque - an increase in power of around 11%. I keep telling him to try gears but he flat refuses to consider it.

If he had spent $650 on gears, going to say 4:88s, he would have increased his power, AND EQUALLY his Torque, by more than 30%. Pretty darned cost effective.

 

4.88s will be just fine for the 33s

 

does re-gearing correct the speedo accuracy?

 

it certainly helps make it closer to stock, though it'll probably still be off a tad

 

what is a good price quote for purchase and install or front and rear gears.?
sorry to hijack but just wondering b/c i have 32's with stock 4.11's and i'm going to move to 33's when my 5inch is installed.
soo sorry to hi jack.
thanks,
alan

 

5" seems a little tall for 33s?

 

I have 4.88's in my 85 xcab with 32 mudders and i feel it's geared too low .I think 33's would be just about right.

 

I have a 92 4x4 with the little 2.4 22RE, she runs 33x12.5 mudd tread with a three inch body, stock gears. I'm thinking about regearing to 4.88's and putting in posi or limited slip, any suggestions. Thanks in advance

Maverick

 

Quotes in my area for regearing both ends (no new diffs, just gear change) ran from $650 to $1300, so shop around. This for 5.29s in a '90.

Mav- 33s & 4.88s sounds just right to me. Suggestions? I really like the Truetrac and it's price is good too. Smooth and quiet and won't wear out in 40k like clutch type posis do.

 

to Kyle 22r, a five inch is not too tall for 33's. everyone with a 4 inch runs 33's and a 5 inch isn't that much more room. The next good size is a 35 and that would be too snug on my rig. I got quoted for front and rear gears and install and it was about 1000$. Does that seem too high or about right. This was at 4wheel parts. I've been told that axle shops do installs for cheaper so i should buy from 4wheelparts and go install somewhere else. right?
Thanks,
Alan

 

then again i drive a 1st gen truck with the huge fender flares, 33s aren't out of the question with the stock suspension

 

Cool, I'll check out the truetrac. But you think that route is better than a posi type set up. Talk soon.

Maverick

 

The clutch type posis wear. I had two TRD LSDs and the rear one was useless by 40k miles. I swapped them around and got good use out of the other one... But the gear type (TorSen or TrueTrac) shouldn't wear at all, and they operate smooth as silk too which is nice. I have friends with them that are quite old and still work perfectly. I guess I'll know firsthand in a few years.

 

Cool, man thanks a lot, I'll start pricing the true trac. ttyl

Maverick