How to adjust the speedometer? - Jeep Wrangler Forum
Jeep Wrangler Forum

Go Back   Jeep Wrangler Forum > TJ Jeep Wrangler Forum > TJ Tech Forum

Join Wrangler Forum Today


Reply
 
Thread Tools

Please support our sponsors and let them know you heard about them on WranglerForum.com
Old 09-02-2010, 05:08 PM   #1
Jeeper
 
nastyrider17's Avatar
 
Join Date: Jul 2010
Location: New Hampshire
Posts: 816
How to adjust the speedometer?

Yet another issue with my TJ. My speedometer says that I am going 3mph faster than I actually am. It's a 2000 sport model with the 4.0l engine and 5spd tranny.

nastyrider17 is offline   Quote
Old 09-02-2010, 05:15 PM   #2
Jeeper
 
Jeepersbatman's Avatar
 
Join Date: Aug 2010
Posts: 64
In your tranny should be a speedo gear, you need to know how many splines are on it. You also need to know your axle gear ratio and tire size. Next check somewhere like quadratech for the correct speedo gear.

Jeepersbatman is offline   Quote
Old 09-02-2010, 05:20 PM   #3
Jeeper
 
Jeepersbatman's Avatar
 
Join Date: Aug 2010
Posts: 64
Oh and nasty not sure of your tire size but it sounds like they are smaller than factory. If so just change your tires to factory size. I was just assuming on my last post you had larger tires.
Jeepersbatman is offline   Quote
Old 09-02-2010, 05:34 PM   #4
Jeeper
 
nastyrider17's Avatar
 
Join Date: Jul 2010
Location: New Hampshire
Posts: 816
I have 31" BFGs. Would I have to remove the transmission to change the speedo gear? Also, my tachometer sticks at 2200rpm (and stays there unless I hit it), how could this be fixed?
nastyrider17 is offline   Quote
Old 09-02-2010, 05:57 PM   #5
Jeeper
 
Join Date: Jun 2010
Posts: 2,121
Gate53 is offline   Quote
Old 09-02-2010, 06:32 PM   #6
Knows a couple things...

WF Supporting Member
 
Jerry Bransford's Avatar
 
Join Date: Nov 2005
Location: Escondido, Calif.
Posts: 35,806
Images: 2
One more link to how to do this with a chart to tell you what speedometer gear tooth count to install. You just need to know your axle ratio and tire size to use that chart. Click on the chart to make it big enough to read... Changing Your Jeep Speedometer Gear
__________________
When you have a choice, buy American.

Jerry Bransford is offline   Quote
Old 09-02-2010, 07:43 PM   #7
Member
 
Join Date: Oct 2009
Location: San Jose Calif.
Posts: 1,006
Being 3MPH off is well within the margin of error. My Dad's brand new Buick is 4MPH off according to his GPS.
03 RUBI is offline   Quote
Old 09-02-2010, 08:08 PM   #8
Jeeper
 
Join Date: Aug 2009
Location: guyton,georgia
Posts: 56
listen to Jerry. he knows what he is talking about. i just changed gears in my 2000 tj auto. and i run on 33's. i called 4wd about the speedo and they told me to change to a 34 tooth speedo,... wrong! i'm running 5-8mph faster on my speedometer than i'm actually running. jerry told me to switch to a 36 tooth speedo and presto, back where i need to be.
ROB719 is offline   Quote
Old 09-02-2010, 08:30 PM   #9
Jeeper
 
Join Date: Feb 2010
Location: North East Ga
Posts: 39
yeah some charts are wrong, jerry knows the correct ones. 3mph is prob "within factory specs" but i understand, and as far as how hard it is, did it today with 1 wrench and less than 5 min total. so its real easy, its located on the tail shaft of the transfer case, pull the bolt and it slides out, put the new gear in and back together, that simple
akswinehart is offline   Quote
Old 09-03-2010, 05:38 AM   #10
Jeeper
 
Neil F.'s Avatar
 
Join Date: Nov 2007
Location: Marlton, NJ
Posts: 6,389
Images: 1
Also what speed is it 3 mph off? The error from different size tires is linear. The error will increase as the speed increases.
__________________
2003 TJ, 33" BFG AT, 2" BL, 2" BDS spring lift, Truck Lite headlights, Homemade sunrider top.
Neil F. is offline   Quote
Old 09-03-2010, 07:08 AM   #11
Jeeper
 
InfernoGirl's Avatar
 
Join Date: May 2009
Location: Newburgh IN
Posts: 11,419
Am I the only person who doesn't hate math? Much easier and free to just remember the speedo is a tad off.... (kinda like me)

__________________

Dirty Mudder column covers|

'01 Wrangler Sport, Sienna Pearl Mine
'07 Rubicon 2D, Flame Red His
'11 Wrangler Sport 4D, Black Ours...

Quote:
Originally Posted by Kate View Post
Not every girl, is a Jeep girl. We're a special breed.
InfernoGirl is offline   Quote
Reply

Thread Tools

Posting Rules
You may not post new threads
You may not 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 Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Speedometer error DCNKY TJ Tech Forum 4 05-10-2010 08:58 PM
Speedometer gear help mike_b_ar YJ Tech Forum 10 01-19-2010 08:07 PM
speedometer dosn't work..what should i check? alexcited YJ Tech Forum 5 03-20-2009 04:20 PM
Color and # of stock Speedometer gear? Yellow 30? jonbugh TJ General Discussion Forum 5 03-11-2008 04:31 PM
best way to adjust speedometer tough_jeep89 TJ Tech Forum 17 01-30-2008 08:45 PM



Download our Mobile App

» Featured Product

All times are GMT -5. The time now is 07:40 AM.


User Alert System provided by Advanced User Tagging v3.1.0 (Pro) - vBulletin Mods & Addons Copyright © 2015 DragonByte Technologies Ltd.

Jeep®, Wrangler, Liberty, Wagoneer, Cherokee, and Grand Cherokee are copyrighted and trademarked to Chrysler Motors LLC.
Wranglerforum.com is not in any way associated with the Chrysler Motors LLC