traxxi2003

Ok, I know this has been brought up before, I've done my research and still need clarification. Here is the information that I found:

I'm in the process of upgrading gears on my truck, since it can barely go up hill with the new 33" tires. The truck in question is my 1997 4Runner SR5 2WD.

First here is a picture of the Vin# plate of my truck:



On the "Sonoran Steel" website, they have an article (1996-2004 ToyotaGearRatio);

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

In this article, if you look up my truck's model number (circled in blue on the picture above), my truck has 3.73 gears. Although 4.10 ratio is also an option for my truck's model number, I believe that the actual gear ratio on my truck is 3.73 since it looks like my truck came equipped with factory 225/75/15 tires. Is my conclusion accurate?

I also found this gear ratio information on the following website: http://www.brian894x4.com/Gearratiosanddiffs.html

On this website they use the Gear Code (circled in red) from the Vin plate. In my case this code is: "A03A" According to this site, my truck has 4.10 and is a 8" axle. Can someone help decode all of this? I would hate to order parts from the internet and then realize I ordered parts for the wrong axle. Thanks!

James Woods

iTrader: (1)

From what I understand trucks with the optional tire size of 265/70r16's got 4.10 gears and since you state that it had the smaller tires and wheels I would think that you have the 3.73 gears

http://www.top4runners.com/runhist/runhist319972.html

I have heard that the second site is a lot of misinformation for the newer trucks.

scuba

Here is an uncommon method I used to figure out the gear ratio in my dad's 99 2.7L 2WD 5speed.

First, get on the highway and do 70MPH (GPS verified 70, cause your speedo is wrong) in overdrive (if that slug will even do 70 in OD LOL). At 70 MPH, write down the RPMS that the tach shows you.

Then go to this site:
http://www.grimmjeeper.com/gears.html

Use the chart on the left.

Step 1, choose your transmission from the drop down menu (I chose A340E like the picture above).

Step 2, just enter "1.00" in the high range box.

Step 3, Leave underdrive alone.

Step 4, Put in the proposed axle ratio. You could start at 3.58, then move to 3.73, 3.9, 4.1, 4.3... etc.

Step 5, self explanatory. Enter the actual metric values for the tires if they are metric 33's.

Step 6, again, self explanatory. Hit "calculate."

After that you will scroll down to the bottom of the page to the final box. There will be 3 columns. On the very right column change the speed from 65 to 70 (if you recorded at A GPS VERIFIED 70). Then hit "calculate" again.
The very bottom row will show you the RPMS of the engine in 4th gear at the speeds listed at the top of the columns. So, the very bottom right boxes value will display an approximate RPM for all of the variables.

Most likely you will have to change the gear ratio once or twice. Thats why I said you "could" start at 3.58 and go up (numerically up) from there.

Let us know what you figure out.

Nelsonmd

A couple things, first, that Brian894x4 page has been bookmarked in my browser since I got my 4runner (one of the first pages I found on these vehicles), and it is frequently wrong. I have run into multiple people here and over on T4r.org for whom that page was completely wrong. My axle code A04A, so according to that page, I should have a 4.56 open diff; I have a 4.30 e-locked diff. Not saying Brian's content is necessarily wrong, but those aren't hard and fast code translations, maybe Toyota was inconsistent with it.

I have seen many discussions about gear ratios, and I (though maybe not everyone else) have come to a pretty strong conclusion... the only way to know is to actually check on your vehicle. Scuba's method for checking is interesting, but I don't think it is that accurate (if there's drag in your car, the revs would be higher wouldn't they?). Fortunately there is a really easy way to check that is very very accurate, it's called the spin test.

1) Put your vehicle in 2WD mode and tranny in N.
2) Jack up 1 rear tire off the ground (leave parking brake off)
3) Crawl under the vehicle and put a mark on the driveshaft (tape, paint, marker, etc.) so that you can see and count the rotations of the driveshaft
4) Do the same to the lifted tire and have a friend slowly spin the lifted tire 20 times while you count the number of revelations of the drive shaft.
Take the number of DS revolutions and divide by 10, this is your gear ratio.

This is the most accurate and error-proof method I have heard of, and it is super easy. If anyone else has easier methods, I would love to hear them.

scuba

Uh, only if the clutch slips.

It had been within ~50 RPM on my truck when I last checked it.


IMO, its easier, less labor intensive, and less confusing than the spin test.

Nelsonmd

less confusing? Bro, read your instructions, then read mine. That page of yours has 105 output windows. You be trippin' man...

Whatever, either is better than going by one of the million chart or tables on the internet that are either wrong, or ambiguous.

traxxi2003

James, I'm not 100% sure if my truck came with 15" wheels from factory. I only made that assumption based on what the VIN# plate shows; Look at the picture above. You will see that on the plate it says that the truck came with "225/75/15". I presume that since is printed on the truck's Vin plate, it must have been what the truck was fitted with at the factory. Although, when I bought my truck back in 2007, it came with 16x7 Toyota wheels. Anyway, tonight I will be testing "SCUBA'S" gear chart on my way to work, so I'll be posting results later on tonight.

traxxi2003

Ok, I took some RPM readings at the following speeds: (Speeds were GPS verified)

Actual readings:
45MPH= 1200-1250RPM's
65MPH= right @ 2000RPM's

Scuba's Gear Chart (with 4.10 gears & 33" tires)
45MPH= 1334RPM's
65MPH= 1927 RPM's

When comparing the numbers you can see that the numbers for the 45MPH range were off by about +-130RPM's. But the numbers for the 65MPH range were off by only 73 RPM's. Based on this numbers I think I do have 4.10 gears on my truck. But to be 100%sure I will be doing the spin test tomorrow, just to compare all the data. What do you guys think?

scrpydoo8

I used this website:

http://www.brian894x4.com/Gearratiosanddiffs.html

and then called Toyota and had them check my vin, and both numbers were the same. Unless you think some major work was done to your truck, i'm sure Toyota would be correct.

Nelsonmd

Holy crap, this is the 4th or 5th time this week I have seen someone post that page as a way to tell your ratio.

IT'S WRONG!!!!!!

Don't mean to jump on you or anything, but that page is totally wrong. It tells me I have a 4.56 open diff when I have a 4.3 locked. And no, I wouldn't trust what Toyota told you either. Not that Toyota is wrong, but because the VIN doesn't 100% coincide with what you actually have for a diff.

Just do the spin test

James Woods

iTrader: (1)

I guess someone didn't read the whole post anyway, what are you doing that you need the gear ratio before you order parts? I do think that the Toyota parts department should be able to tell you by the vin, I have never worked for Toyota but with GM and Subaru they can tell those things by the vin. Also I have never used it but I found this site that decodes your vin and will give you all kinds of specs.

http://www.decodethis.com/Default.as...GN87R5W0075339

scuba

I'd bet that you're 33's aren't true 33's and are about 32.6-32.8"

If you put in 32.6" for the tires the numbers get pretty accurate.
Sounds like you do have 4.10's.

Nelsonmd

Oh James Woods... didn't you read the whole post? VIN does not tell you the gear ratio.

James Woods

iTrader: (1)

I said in my post that I thought it should not that it absolutely does, I was taking what you said as opinion and not as fact, I would think the vin should give you a build sheet sort of say and you can tell from that, at least other manufactures have this, I would think that Toyota would as well.

and the reason I posted that site was just so he can see what tire size it came with, from looking at it, it will tell you under the general tab, but like I said, I have not used it so I cannot vouch for it's accuracy, I was simply offering it as another tool for the OP to use to find what his truck came with from the factory.

traxxi2003

James, I apologize, i guess I should have explain why I created this thread in the begining; Th reason why I needed to know my gear ratio, is because I wasn't sure if I had 4.10 or not. You see, if my truck came equipped with the 3.73 gears, jumping from that to 4.88 in my opinion would be a huge jump. I don't want to be doing 65MPH with my eng running to high on rpm's. Now, Why am I considering going to 4.88? Whell it seems that everybody agrees on running 4.88 ratio if you have running 33" tires. I hope that explains my silly question in regard to the gear ratios. I do have another "stupid" question; Do all the 3rd Gen 4Runners have the so called 8" rear axle?

traxxi2003

I need help again: As you all know, I'm looking to re-gear my rear axle to 4.88. I came across this 3rd member on EBAY. Will this be a direct bolt-on replacement for my 1997 4Runner SR5 2WD? Here is the link:

http://cgi.ebay.com/ebaymotors/Toyot...item5198c81b4e

P.S The auction states that is a "G" differential. My trucks differential code is A03A, according to the Vin Plate.

James Woods

iTrader: (1)

You do have the 8inch rear diff in your truck, and the only thing that I see being a problem is the spline count on the pinion which is an easy fix and the rear speed sensor on the diff which I don't know where yours is but I wouldn't think that would be a problem either.

KZN185W

iTrader: (1)

from what i know, the 8" rear diff is standard on the 3rd gens. the only major difference are those with 2-pinion diff and 4-pinion diff. I think the 4-pinion diff is standard on the V6 versions and those with the rear diff lock. on the speed sensor, it is standard for the 3rd gens with ABS. the diff in the link is not from a 3rd gen but it has the rear diff lock. i think, it comes from a 1992-1995 toyota truck. it may or may not fit on your 4Runner

James Woods

iTrader: (1)

The one in the link is a 4 pinion diff, I am not sure what rear diff lock is being referred to here, but the 2nd gen trucks and runners did not come with a locker stock.

KZN185W

iTrader: (1)

my mistake, i thought the cable was for the RDL. i realized that it is for the rear abs sensor basing on the part number 89544-35030.

this rear sensor is different from the abs sensors on the 3rd gen 4Runners