Correcting Your Speedometer

[BlackWorksInc]

So I joined the Lifted Club and threw some 285/70R17 Nitto Terra Grapplers on my righ recently and the speedo thing is a small thing that will eventually drive me nuts...

My gas mileage has not been that great since I don't drive more than a couple miles at most a day, roughly hovers around 12~14mpg. This past Thanksgiving we took my 4Runner out to some family and it was close to 340miles total driven, with 80% at speeds above 65mph. My mileage was still only about 14mpg... Thinking back on it tonight I was running possibilties through my head, sluggish A/F Sensors, or Sluggish O2 Sensors, need to relearn my fuel map, ect ect... then I remembered that our 4Runners use wheel speed to measure speed and consequently odometer reading.

Long story short, did a few searches and found little in the way of help toawards recalibrating our speedos. Toyota does not list a procedure for it and you can't modify it with the Scantool... bummer. Checked the forum and found some posts that had some helpful bits in it.

So that brings me to this thread. I know there are more than a few products out there for this job and I was hoping people could chime in on their experiences and ideas?

I pulled these from Toyota 120:
Speedometer correction - Toyota 120 Platforms Forum
Speedometer and ABS Adjustment? - Toyota 120 Platforms Forum

I am going to look into the Speedohealer more, but lets go ahead and use this as a dumping ground for ideas, possible solutions, products that may be worth looking at. That way when we tell people to search later on we can have less :smashputer: and more :surfer: trying to find it.

 

[TRDCal]

I have this same issue, I only went from 265/65s to 265/70s and now my speedo reads 95 when i'm doing 100 kph. I was hoping a Toyota tech like yourself would have a easy fix but I guess its not as simple as I thought. Bummer.

EDIT: seems like the speedohealer is the way to go, for now its not my priority but seems like a reasonable solution. I just wish that scantool (or equivalent) had this function so then it could be a more useful 100 bucks spent.

 

[08T4R]

I have used a speedohealer, but it was on my bike. They're useful when changing sprocket sizes and rear tire sizes. Plug in a few numbers and enter the correct calibration in the healer, and mine connected inline with the factory harness, works like a charm. Can even be checked with gps units these days..I'm sure if you know the vss wire it would be an easy tap if no harness is available from speedohealer..

 

[CXS]

I have a Limited and there's a "calibrate for new tires" setting on the nav unit. I'm not sure whst it's supposed to relate to but my speedo is spot-on with the roadside speed detectors. I have no idea how it relates to the mpg calculations because I don't pay any attention to that.

 

[08T4R]

Only thing Ill point out about the speedohealer, is if you get the digital one with the top speed recall, when you recall your top speed it will also roll your odometer like you are moving at that speed. I think it shows the top speed for like 3 or 5 seconds, which is long enough to tack on an additional 1 or 2 0/10th's depending on how fast it is displaying..

 

[marcus6867]

I did the Speedohealer on mine after I installed the 285's. Simple install, took about 15 minutes total. It has worked flawlessly for about 2 years now, my in dash navi and my odometer show the same speed, something that was driving me crazy before!:hatsoff:

 

[NJshadow93]

I saw the write-ups...it looks like the speedo healer requires taking the dash apart. is this true?

 

[BlackWorksInc]

Just removing the instrument cluster.