Hi everyone! I have a 2001 4Runner SR5 2WD Automatic and I love this thing! I'll be posting more often now that I'll be modding my 4Runner since I've had it pretty much stock since 2011 when I got it, and include pictures soon too!

Anyway, I just changed from the original 225/75/15 to the 265/70/16 (31") on new FJ TRD wheels. I did notice a bit of a loss in peppiness as the tires are larger than the original. I know that at about 70 on the speedo I'm really doing about 75 based on GPS.

I want to correct the change in tire size by regearing as I will be towing my track car with my 4Runner. From what I can gather, I either have a 4.30 or 4.56 gear ratio, and It looks like I'd need to go to a 4.88 gear. Does that sound about right? There's so much back and forth from different forums and people referencing links that don't come up anymore so I'm trying to get some clarification and recommendations.

Questions:

Which best/appropriate gear ratio with 265/70/16?
What's a good high quality brand for the gear set?
Recommended SoCal shop that can do the job?

Thanks everyone in advance, I really appreciate the help!

Mine has those size tires stock but I have 4.10 gears and is a 1996. I also have a manual 5 speed.

I would look up what gearing came stock for that size of tire with whatever transmission you are running and then go from there.

Yes, with bigger tires and same size gearing you are going to feel like you are losing power because you are turning a bigger and heavier tire.

https://tiresize.com/chart/ You can go to the link I posted and figure out what you think you need by playing around with the calculator.

Changing gears is not a cheap endeavor so you probably only want to do it once.

265/70R16 was an available tire size from factory.

There should be no need to re-gear unless your vehicle came with the lowest gear ratio available, which I believe was 3.90 or 4.10.

But if you think you have 4.30 or 4.56 gears... I don't think you need to worry too much about the upsize in the wheel. as an example, I have a '97 Limited w/E-Locker, and from factory it came with the 265/70R16's and I have 4.30 gearing.

So to answer your primary question, Toyota deemed that 4.30 was an appropriate gearing for 265/70R16 tires.

And if I read correctly, yours is a 2wd, so I doubt you have any added armor or extra weight like a swing out tire carrier or anything like that. So you're not exactly robbing power elsewhere except for the change in tire size. I think you'll be fine as-is, cause I don't think re-gearing is worth the hassle in a lot of cases unless you're doing hardcore stuff.



That's just my opinion though.

Being that his is 2wd with the smallest tires from the factory, I bet he has 3.73 gears. That was the lowest gear ratio available in the 2wd 4Runners. My 2000 was the same way. 3.73 gears and 265/75R16 AT's wasn't exactly the best combination for speed and towing.

I would suggest at minimum an upgrade to at least 4.10's for 31's. Since you will be towing, try to find a set of 4.30's for just a little more umph in the low end.

OP, what is the gear code on the sticker on your drivers door sill? I bet it is A01A which is 3.73's.

You will be better of getting a supercharger. People run 4.88s on 33 to 35 inch tires.

Ding ding ding! Winnner!

I would also put my money on that you have the smallest possible gears, the 3.73. If you went to 3.90 gears, the speedo should be spot on.

A quick reference for 4Runner gears:

90% of all 4WD 4runners have 4.10 gears. 4.30 is what you'll find for those with a rear locker.

2WD 4Runners came with 3.90 gears, unless you have a 15" wheel 2WD 4Runner (kinda rare actually), which came with the 3.73.

As others have said, 4.30 only came on 4wd, Limiteds with e-locker.
4.56 only came on 4wd, 5 speed 3RZ 4cyl.

You probably have 3.73 or 3.90. Check your door sticker, then do the spin test. My door sticker was correct but many aren't. You can upgrade to 4.10 (most common) or 4.30 pretty easily from the junk yard.

Except 6cyl / 5 speeds w/ e-locker came with 4.10.

So first off thanks again everyone for the info! I just want to reiterate (since I originally left this out in my first post and then edited it) that my 4Runner is an Automatic.

I just checked my door jam sticker and it indeed says A01A, so 3.73 gears confirmed? I don't believe these are as rare as people think because I've seen a number of V6 4Runners with 15" wheels, as mine originally was.

What's the code of a 3.90 gear and what did it come off of? Isn't it supposed to be 3.91 for the 3rd gens? To get to stock 16" wheel gear ratio I need a 3.90/3.91?

Or, as 88Toy4x4 suggested I should go to a 4WD 4.10 gear (A03A) as an upgrade?

As far as more power, I'd probably do a 2UZ-FE swap before going the supercharger route, that's a much further in the future upgrade tho =)

Thanks again guys!

If the goal is to get your speedo back to normal, then 3.90's. If you looking for a lower gearing, then 4.10's but your speedo will be off in the other direction.

Ok, so does anyone know the axle code for the 3.90 gear? If I go hunting at the salvage yards I'll need to know so I can hopefully specify the correct axle. It seems like I can find everything except the 3.90 code when searching.

Or, should I just purchase a new 3.90 gear set and have my rear end serviced with new seals and bearings? Can anyone recommend a good/trusted brand for the gear set?

Thanks!
Eric

Not worth it.


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If you are going to the work, and spend the money, just get the 4.10's.

Here is a better way to find the correct axle ratio in the yards.

http://www.sonoransteel.com/includes...aGearRatio.pdf

my 01 had 16's when i bought it and has the A03A/4.10 rear, but sticker lists 15 tires. i also noticed that it is a 7.5 ring gear. i assumed it was an 8" ring gear. what 4runners, if any, had the 8 " ring gear?

All 4Runner door stickers list 15" tires... so that's no clue.

V6 auto 15" wheel trucks will have 3.73 gears. That's what my '99 had.

Changing gear ratios will not change the speedo on any 4Runner with ABS (which all 2001/2002's had). The speedo is driven by the ABS system from wheel speed sensors. You will need to put a speedo calibrator on the signal from the ABS box in the passenger footwell that goes up to the gauge cluster. Imgur is having an issue, otherwise I'd show you a pic of one in my truck...

You will be happy with 4:10 gears, which will get you very close back to how your truck was stock. You should be able to get the stock diff from many 4WD 4Runners that have been upgraded.

-Charlie