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Just like the title says, how do I find out what gearing I have in my Tacoma? I am 95% sure it is the stock configuration. It is a 1998 tacoma with the 2.7 4 cylinder with a 5 speed. The truck is an extended cab, no TRD, but it is SR5. Im like the fourth owner, so I have no window sticker or any other dealer purchase info...

how do I find out?? is the a serial number or perhaps through the VIN #?


~James
 

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speed answer here about the "Spin and Count Method"

If you have an open diff (no locker), jack up the rear end of your truck, one side only.

Put a visible mark on the driveshaft.

Spin the tire that's on the air two full turns. While doing that count how many times the driveshaft rotates while spinning the tire twice. Of course, pay attention to the mark you put on the shaft beforehand.

4 full turns on the shaft and a little more (4.10's), 4 and another half (prob. 4.30 or 4.56), etc.
 

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Don't forget to have your truck in neutral, wheels chocked, and E-Brake off before spinning the rear wheel too.
 

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partyman66 said:
Don't forget to have your truck in neutral, wheels chocked, and E-Brake off before spinning the rear wheel too.
yep, sorry forgot about that.

Also, if you don't have a locker but a limited slip differential, the method is different, but i can't remember how it goes with a limited slip.

somebody else might clarify that.
 

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stumptaco said:
Just like the title says, how do I find out what gearing I have in my Tacoma? I am 95% sure it is the stock configuration. It is a 1998 tacoma with the 2.7 4 cylinder with a 5 speed. The truck is an extended cab, no TRD, but it is SR5. Im like the fourth owner, so I have no window sticker or any other dealer purchase info...

how do I find out?? is the a serial number or perhaps through the VIN #?


~James
with the manual you have either 3.58, 4.10s but most likely 4.10s
 

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Deal Master
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ben90 said:
yep, sorry forgot about that.
Also, if you don't have a locker but a limited slip differential, the method is different, but i can't remember how it goes with a limited slip.
somebody else might clarify that.
If you are LSD/or locked in in the rear - You can jack up both rear tires.
(ie drive shaft will rotate 4.1 times for every 1 axle/wheel rotation)


When you are open rear- If you jack up the entire rear end-
You will be off by a factor of 2 if you rotate the wheel once and count the # or Drive shaft/ pinion rotations.
(ie drive shaft will rotate 4.1 times for every 2 axle/wheel rotations if open & both wheels in the air)

That's why you only jack up one side when open
(ie drive shaft will rotate 4.1 times for every 1 axle/wheel rotation if one wheel is one the ground)

In the Case of 4.1's -
Your pinion gear basically has 10 teeth while your ring gear has 41 teeth.
 

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grillmasterp said:
If you are LSD/or locked in in the rear - You can jack up both rear tires.
(ie drive shaft will rotate 4.1 times for every 1 axle/wheel rotation)


When you are open rear- If you jack up the entire rear end-
You will be off by a factor of 2 if you rotate the wheel once and count the # or Drive shaft/ pinion rotations.
(ie drive shaft will rotate 4.1 times for every 2 axle/wheel rotations if open & both wheels in the air)

That's why you only jack up one side when open
(ie drive shaft will rotate 4.1 times for every 1 axle/wheel rotation if one wheel is one the ground)

In the Case of 4.1's -
Your pinion gear basically has 10 teeth while your ring gear has 41 teeth.
thanks for the clarification :D
 

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How to figure gear ratio.....

Ok, so I've got a '98 2.7L 5-speed, manual hubs and what not. Is there any way to figure out EXACTLY what gears I have (aside from pulling them out and counting them)? :(

The only reason I ask, is that I'm not sure that I have the 3.58's. Acceleration doesn't seem sluggish to me and I have 30x9.50's. I've been on the trails and crawled over a fair share of rocks, given that I have no lift. It's never dissapointed me yet as far as speed and acceleration on road or off. But I don't have anything to compare it to (like another truck with known gears), and I don't have a tach.

I've also read that the code guide in the tech file is not always accurate, and I've seen other places on the web that states the same thing.

If any of you are familiar with Aetna Mtn, TN (near Chattanooga), I've made it up Jeep Top and I have been told that it was quite a feat since I'm stock. I just don't see that happening with inferior gearing. The guy who went before me was SAS'd, locked Fr/Rr, geared, & had at least 35's. He got stuck. Everyone was impressed that I made it up the trail w/out help. :cool:

Ok I'm done bragging.

Any ideas??
 

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Fox4Rnr said:
Ok, so I've got a '98 2.7L 5-speed, manual hubs and what not. Is there any way to figure out EXACTLY what gears I have (aside from pulling them out and counting them)? :(

I've merged your thread with an identically asked question.
Please read above posts

No need to pull the diff- count the ratio of pinion : axle rotations
I don't trust door jam codes either-
Dealers have made mistakes as well-

Contact Toyota USA with your VIN #
 

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OK, did the driveshaft method.

At first, Ionly jacked up one side and I was getting 1.8 ds turns to 1 tire turn. Thats not right.

So I jacked up the entire rear end and did it and low and behold I got 3.58, roughly. So I do have 3.58's but a LSD, too? Maybe thats what gave me my "advantage" on the trail. Guess I'll be getting 30's or maybe 31's instead of 32's, when I get my tires.
 

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Or you could just enter your tire size into this speed/RPM calculator site that I will link you to, and then go drive next to someone at 65 MPH on the highway and see what your RPM's are, and you should be able to determine which gear you have back there by combining those 2 pieces of info.

http://www.car-videos.net/tools/speedrpm.asp?Car=Select&Num1=275&Num2=70&Num3=16&AxleRatio=4.091&Ratio1=3.954&Ratio2=2.141&Ratio3=1.384&Ratio4=1.0&Ratio5=.810&Ratio6=&Ratio7=&Redline=6250&Increment=100&B1=Recalculate

That site has been a bit slow lately, but the link I posted already has the info entered for the W59 transmission(4-cylinder 5-speed), so you just need to adjust the gear ratios and tire size to figure out what RPM you'd be at for various speeds.
 

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partyman66 said:
Or you could just enter your tire size into this speed/RPM calculator site that I will link you to, and then go drive next to someone at 65 MPH on the highway and see what your RPM's are, and you should be able to determine which gear you have back there by combining those 2 pieces of info.

http://www.car-videos.net/tools/speedrpm.asp?Car=Select&Num1=275&Num2=70&Num3=16&AxleRatio=4.091&Ratio1=3.954&Ratio2=2.141&Ratio3=1.384&Ratio4=1.0&Ratio5=.810&Ratio6=&Ratio7=&Redline=6250&Increment=100&B1=Recalculate

That site has been a bit slow lately, but the link I posted already has the info entered for the W59 transmission(4-cylinder 5-speed), so you just need to adjust the gear ratios and tire size to figure out what RPM you'd be at for various speeds.
the problem with using that is you need the exact tire diameter, not what is stamped on the side and your speedo must be accurate...which his is not with most likely 3.58s and 30" tires with a speedo gear that is meant for 28s :rolleyes:

Oh, and the gear code chart that has been posted numerous times on this site is quite accurate ;)
 

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hytenor said:
the problem with using that is you need the exact tire diameter, not what is stamped on the side and your speedo must be accurate...which his is not with most likely 3.58s and 30" tires with a speedo gear that is meant for 28s :rolleyes:

Oh, and the gear code chart that has been posted numerous times on this site is quite accurate ;)
The difference will be negligible enough for him to differentiate between 3.58 and 4.10 for absolute certainty and also most likely to differentiate between 4.10 and 4.30. The reason I mentioned pacing with another car going 65 was to account for the potential inaccuracy of the speedo based on tire size.... so you use another car which is somewhat accurately callibrated and drive beside it or behind it when it's going 65 MPH and see what your RPM's are. I did this with my truck and and my brothers car it worked out pretty damn accurately to verify the gears that I already knew I had.
 

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Thanks, but I don't think thats gonna work for me, since I don't have a tach, but I'm sure others will be able to use it. :D
 

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How to determine axle ration on 96 Tacoma?

Hello,
Is there an easy way to tell if I have the 3.58 or the 4.10 ratio rear end? It's a 2.7L 4x4 manual tranny truck.

Thanks,
Fred
 
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