question about speed and rpm with bigger tires - : Jeep Wrangler JK Forum
LinkBack Thread Tools Display Modes
post #1 of 2 Old 06-04-2015, 10:20 PM Thread Starter
Granite Guru
Join Date: Dec 2014
Age: 33
Posts: 261
Feedback: 0 reviews
question about speed and rpm with bigger tires

hey. i just purchased another JKU, its a Sahara, 2007, mexican. i drove about 700 miles from where i picked it to where i live.

most of the time it was a flat, long desert highway, with very light traffic, basically empty. so i adjusted the cruise control to 80 mph, and i noticed the tachometer was a little under 2500 rpm. i also tried going at 70 mph and the tacho was just over 2000 rpm.

now, the jeep has 285/70 R 17 BF Goodrich Mud terrains, almost new, so they have a lot of live (and weight) on them.

and i checked the speed with my cell phone gps and it was within 1 mile of what the speedmeter said.

all of this made me wonder, did the PO had something adjusted on the computer?? i know i can check if the jeep is regeared by lifting a tire and counting how many times it turns and how many times does the driveshaft turns... but how can i check if they did something with the computer??

i averaged about 16 MPG....

2007 JKU, 2.5" Rock Krawler lift, 285/70 17 mud terrains....
shu2kill is offline  
Sponsored Links
post #2 of 2 Old 06-04-2015, 10:51 PM
Granite Guru
Join Date: Jun 2013
Location: utah
Posts: 149
Feedback: 0 reviews

well it sounds like the computer has been adjusted to compensate for the bigger tires. not sure how to check it though.

opinions are like a$$holes, everyone has one and some stink
grumpy5 is offline  
Sponsored Links

Quick Reply

Register Now

In order to be able to post messages on the : Jeep Wrangler JK Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:


Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

For the best viewing experience please update your browser to Google Chrome