Speedometer correction

[TwistedCU]

Ok, going to put my new tires and wheels on the XJ today, and I want to correct the speedometer soon. I understand the cheapest way and the correct way is to get a new speedo gear. Anybody got any info on where to get one, which one to get and any tips on installing it?

I have the 4.0L, 3:55 gears, an automatic, and the tires measure to 30.7"

 

[jps4jeep]

three letters

B F H

JK
Take you tire sixe and you gear ratio to the dealership and give them that info (also the engine and transmission set up) and they give you a new gear, pretty easy to install. on the back of the Tcase prior to the slip shaft you will see the speedo plug, unplug and then you will see a (i think) 7/16 bolt. mark the orientation of the female end of the plug, remove the bolt and slide that assembly out. on that assebly you will see the gear that you are re-placing. swap them over, slide it back into the housing making sure it is the same as the way it came out, plug in, badda bing!

Also cause you have a electronic speedo, you can use those computer correction units which might be a little better, save money in the long run.

 

[TwistedCU]

Not sure the electronic correction unit is economical. They're just under $200

Thanks for the info, I'll swing by the stealership when I get a chance

 

[Bounty__Hunter]

There are many speedo gear charts on the web that will give you the correct part number. Take your speedo assembly to the stealership with you to ensure you get the correct style speedo gear.

Go to the stealership armed with the part number. Looks like you need part #52067633:
http://www.raingler.com/jeepReference/speedoChart.html
http://www.sierrajeep.com/speedome.htm

 

[jeeperjoe]

wont the electronic correction take care of the shift points as well? i thought i would need one but i dont really notice the transmission shifting at odd times.

 

[_(OIIIIO)_Jeeper]

.....I could be wrong (usually am)...but doesn't the shift go off the RPM's?

 

[phatyaspen]

i got the superlift truspeed it sux! do not buy!!!! they neglect to tell you until you get it that it cant be used with 33's and 4.88 gears... all i got was why are you not running bigger tires and sarcastic comments from superlift customer service... now i have 35s so id unno well ahve to make some adjustments..but theyre customer service smells like yesterdays diapers

 

[Bounty__Hunter]

XJ autos use the speed sensor as one of the inputs for transmission TCU performance, so it's best to be running the correct speedo gear. I don't think the Wrangler autos use a TCU.

 

[TwistedCU]

wont the electronic correction take care of the shift points as well? i thought i would need one but i dont really notice the transmission shifting at odd times.

Now that I've driven it to work, I have noticed a small difference in the shifting. The speedo isn't off too badly according to my GPS, but I'm going to change the gear just to keep the transmission operating accurately.