Too high of gears? 91 4x4 M/T, confused...
#1
Registered User
Thread Starter
Too high of gears? 91 4x4 M/T, confused...
So, I've got an interesting situation that I can't make sense of. The sticker says that stock, I'm supposed to have 225/75 R15 tires (which I do, for now) and that I've got G254 gears (4.56).
Here's the part I'm confused on. I know that the previous owner had 31's on it, since the spare is a 31. However, those aren't stock according to my doorjamb. Recently, I've noticed that my odometer was running a little high compared to my GPS and Google Maps and it turns out it's right, when the speedometer reads 70 MPH (highway speed) I'm actually going only 64 MPH! Also, my engine revs at 3200 RPM at "70". From here to my parent's house it's 91 miles, but my odometer will read 100.
Here's what the door jamb says so you know I'm not going crazy.
So... anyone know what size gears I actually have? Or did stock gears read high straight off the factory floor? Is there any way to check?
P.S. And on a final note... that means my MPG is only 15 city and 20 highway . I thought I was getting 16.5 city and 22 highway... still at 33% improvement over when I got it but the high numbers were fun to brag about...
Here's the part I'm confused on. I know that the previous owner had 31's on it, since the spare is a 31. However, those aren't stock according to my doorjamb. Recently, I've noticed that my odometer was running a little high compared to my GPS and Google Maps and it turns out it's right, when the speedometer reads 70 MPH (highway speed) I'm actually going only 64 MPH! Also, my engine revs at 3200 RPM at "70". From here to my parent's house it's 91 miles, but my odometer will read 100.
Here's what the door jamb says so you know I'm not going crazy.
So... anyone know what size gears I actually have? Or did stock gears read high straight off the factory floor? Is there any way to check?
P.S. And on a final note... that means my MPG is only 15 city and 20 highway . I thought I was getting 16.5 city and 22 highway... still at 33% improvement over when I got it but the high numbers were fun to brag about...
#3
Registered User
Thread Starter
I read that the dot isn't always accurate either especially if suspect that gears have been changed (4crawler.com).
Speedo converter
Original Tire Diameter: 31 (what used to be on there)
New Tire Diameter: 28.3 (225/75 R15)
Speedometer Reading (MPH): 70
Corrected Speed (MPH): 63.9
Taken from this site: http://www.jtoutfitters.com/pages.php?cID=2&pID=11
Does this mean my truck was made for 31"s and my doorjamb lies? If it helps at all, I run at 3200 RPM at "70" (really 64 MPH).
Speedo converter
Original Tire Diameter: 31 (what used to be on there)
New Tire Diameter: 28.3 (225/75 R15)
Speedometer Reading (MPH): 70
Corrected Speed (MPH): 63.9
Taken from this site: http://www.jtoutfitters.com/pages.php?cID=2&pID=11
Does this mean my truck was made for 31"s and my doorjamb lies? If it helps at all, I run at 3200 RPM at "70" (really 64 MPH).
#4
Registered User
iTrader: (1)
Join Date: Mar 2013
Location: Mobile, Alabama
Posts: 2,121
Likes: 0
Received 0 Likes
on
0 Posts
If your truck has 28in tires and 3200rpm at 64mph it works out to 5.07 gear ratio if your transmission is in 5th (0.83). Your tach could be off also but I wouldn't think that much
#6
Registered User
My door jamb info looks just like yours, however, I have 456 g254 gears and 31s. I was told that they imported our trucks with smaller tires because the tariff was cheaper and installed larger tires after they got here. I dont know that for sure, thats what a dealer told me. He also told me they imported all of our trucks without ac and installed it over here to save money. Mine is a 90 sr5 v6. I was also told that mine wasnt imported as an sr5, that most of the add ons was done here and that kinda makes sense looking at the door info and I know mine was sold new with 31s. He told me that most trucks were imported as base models because of the cheaper tarriff, and basically remanufactured here. That would explain the door info being right on the gears and wrong on the tires. Im not putting this out as gospel, this is what a dealer who is a friend of mine told me. Hope this helps.....
#7
Registered User
Join Date: Feb 2011
Location: Hammond, LA
Posts: 384
Likes: 0
Received 0 Likes
on
0 Posts
recently i bought a bluetooth OBD 2 adapter and an app for my phone that shows computer info. i've found that my GPS and the torque app reads differently from my speedometer. both read up to 3-4 MPH different than my speedometer shows. my truck is stock. so honestly i trust the actual speedometer more than anything
Trending Topics
#8
Registered User
Thread Starter
My door jamb info looks just like yours, however, I have 456 g254 gears and 31s. I was told that they imported our trucks with smaller tires because the tariff was cheaper and installed larger tires after they got here. I dont know that for sure, thats what a dealer told me. He also told me they imported all of our trucks without ac and installed it over here to save money. Mine is a 90 sr5 v6. I was also told that mine wasnt imported as an sr5, that most of the add ons was done here and that kinda makes sense looking at the door info and I know mine was sold new with 31s. He told me that most trucks were imported as base models because of the cheaper tarriff, and basically remanufactured here. That would explain the door info being right on the gears and wrong on the tires. Im not putting this out as gospel, this is what a dealer who is a friend of mine told me. Hope this helps.....
I double checked the accuracy of the GPS by comparing with my wife's '11 Nissan Altima. GPS said 70, Speedometer read 70.
#9
Registered User
iTrader: (1)
From how your speedo is reading higher than actual speed it sounds correct that you are geared lower for the tires you're running. It's good for low end power and city/trails but not ideal for highway trips. I personally would mess with gears, I would just swap to 31" tire which should balance everything out- also fills out the wheel wells more without any rubbing anywhere. 31s can be found all day long on CL used. Also you have a good selection of new tires in this size since its so common for stock SUVs to come with them. Price is significantly less than what a 33+ costs these days.
#10
My truck is a DLX. Door jam says 225/75r15 has had 31/10.50r15 since new. Speedometer reads spot on. Spare tire and factory tires had 31's aftermarket extra's also had 31's. So I would say put 31's on and it should be good.
#11
Registered User
Join Date: Nov 2012
Location: florida
Posts: 698
Likes: 0
Received 0 Likes
on
0 Posts
#12
Registered User
You've got 4.56 gears, which is the gearing for the 31" tire package with manual trannies. The autos w/ 31" package got the 4.88s.
See here: http://www.brian894x4.com/Gearratiosanddiffs.html
The bottom half of this page has several other fyis for gearing etc: https://www.yotatech.com/forums/f116...51/index2.html
See here: http://www.brian894x4.com/Gearratiosanddiffs.html
The bottom half of this page has several other fyis for gearing etc: https://www.yotatech.com/forums/f116...51/index2.html
#13
Registered User
My door jamb info looks just like yours, however, I have 456 g254 gears and 31s. I was told that they imported our trucks with smaller tires because the tariff was cheaper and installed larger tires after they got here. I dont know that for sure, thats what a dealer told me. He also told me they imported all of our trucks without ac and installed it over here to save money. Mine is a 90 sr5 v6. I was also told that mine wasnt imported as an sr5, that most of the add ons was done here and that kinda makes sense looking at the door info and I know mine was sold new with 31s. He told me that most trucks were imported as base models because of the cheaper tarriff, and basically remanufactured here. That would explain the door info being right on the gears and wrong on the tires. Im not putting this out as gospel, this is what a dealer who is a friend of mine told me. Hope this helps.....
But to the options and whatnot by year, I find the sales brochures super informative: http://www.toyotareference.com/truck
Last edited by RSR; 08-18-2013 at 06:50 PM.
#15
My door jamb info looks just like yours, however, I have 456 g254 gears and 31s. I was told that they imported our trucks with smaller tires because the tariff was cheaper and installed larger tires after they got here. I dont know that for sure, thats what a dealer told me. He also told me they imported all of our trucks without ac and installed it over here to save money. Mine is a 90 sr5 v6. I was also told that mine wasnt imported as an sr5, that most of the add ons was done here and that kinda makes sense looking at the door info and I know mine was sold new with 31s. He told me that most trucks were imported as base models because of the cheaper tarriff, and basically remanufactured here. That would explain the door info being right on the gears and wrong on the tires. Im not putting this out as gospel, this is what a dealer who is a friend of mine told me. Hope this helps.....
Thread
Thread Starter
Forum
Replies
Last Post
RedRunner_87
95.5-2004 Tacomas & 96-2002 4Runners (Build-Up Section)
84
06-01-2021 01:51 PM
Poncho0206
95.5-2004 Tacomas & 96-2002 4Runners
3
07-10-2015 06:21 PM