Speedo correction solutions?

[ChrisD]

With the tires/gears my speedo is off. Because my wife also drives the jeep, I would like to correct the reading. Looking for a solution to correct my speedometer and found some threads on JF regarding a product called SpeedoHealer. Just wondering what other solutions are available.

http://bluemonkeymotorsports.com/products_ht.html

[Kurt]

How many % are you off?

[Baseshakers]

Np231 or rubi tcase?

[ChrisD]

Kurt... based on the GPS 30mph my speedo reads 40-45

rubi case

[Kurt]

Wow... that's off a lot, about 40% higher than actual.

A few questions...
1) what was your stock gearing and what is your current gearing?
2) 33" tires on it now as I recall
3) did you use the Rubi speedo sensor and wire it up to your Jeep or did you use an aftermarket on?

[Hoodoo Man]

Wow didn't realize the rubi tcase was so different. Tell you what i'll swap you my np231 w sye and the correct speedo gear.

What about just getting a aev programmer?

[Kurt]

Chris is running the Rubi tcase. It does not use a speedo gear like a older NP231 tcase.
Changing out a gear isn't an option on the Rubi tcase.
The Rubi speedo sensor is a "hall effect" sensor (no gears involved). Instead of a gear in the tcase the rubi uses a tone ring with some magnets in it.
The sensor "sees" the changing magnetic field of the tone ring rotating with the tcase output shaft.

The same exact scheme that ABS wheel sensors use in many vehicles.

[Modeler]

Chris, I've been using the Superlift one for about 6 years now. I put in in when I went to 33's and adjusted it without issue when I made the change to 35's. The only thing is that you have to cut and splice to install it. Not sure if you have to do that with the Speedohealer. At the time I got it, the Superlift was really the only game in town.

[Elias 4WD Center]

What year is your Jeep?
PRobably very easy to use the AEV ProCal, that we keep stocked here...
Around $150 n tax

[ChrisD]

Wow... that's off a lot, about 40% higher than actual.

A few questions...
1) what was your stock gearing and what is your current gearing?
2) 33" tires on it now as I recall
3) did you use the Rubi speedo sensor and wire it up to your Jeep or did you use an aftermarket on?

1) Stock 3.73 / Now 4.56

2) 33"s

3) I am 98% sure I am using the Rubi sensor

[ChrisD]

What year is your Jeep?
PRobably very easy to use the AEV ProCal, that we keep stocked here...
Around $150 n tax

2003

Same price as the one I mentioned...

[Elias 4WD Center]

What year is your Jeep?
PRobably very easy to use the AEV ProCal, that we keep stocked here...
Around $150 n tax

2003

Same price as the one I mentioned...

My bad - ProCal is for JK only.

[mark2215]

Yellow Box is what I use to correct the speedometer on my jeep. It does involve splicing a few wires for the cheaper model but they might offer a model that has a plug and play harness, I'm not sure. It works and was less than $100.

[Kurt]

Wow... that's off a lot, about 40% higher than actual.

A few questions...
1) what was your stock gearing and what is your current gearing?
2) 33" tires on it now as I recall
3) did you use the Rubi speedo sensor and wire it up to your Jeep or did you use an aftermarket on?

1) Stock 3.73 / Now 4.56

2) 33"s

3) I am 98% sure I am using the Rubi sensor

Something doesn't add up.

The higher gear ratio and the larger tires should offset each other but not perfectly.
By my calculations I'd expect your speedo to be off by 11% and not the 30-40% you are seeing.

[ChrisD]

Will have to double check Thursday.