Change tire size calibration for larger tires 2012 FJ (1 Viewer)

[Toy4x4s]

I just got new tires, went up in size very slightly. Was 265/70/17, now 285/70/17. Before I did this I was told by my dealer (sales manager) that there was a device the service dept could plug in (OBD-2?) that could communicate with the electronic trans (auto trans) and you simply program in the new tire size and it recalibrates the speedometer to read correctly for that size. He said the service dept orders it for you, you bring FJ in, they make the change and you get to take the connector thingy home. Costs an hour of labor and the connector cost, about $175

I just called my parts dept and they spoke to the service tech. They say there is no adjustment for that.

What have you guys done to recalibrate speedo for larger tires? I know with the FJ40 there was a little gear that went into the transfer case that connected to the speedo cable.

Thanks for the help!
June Bennett
Cheyenne WY

 

[Corey]

Same here, I went from 265/70/17 to 285/70/17.
Did not need to recalibrate at all, the onboard super duper computer must have done it for me.

I have an indash GPS on my DVD Nav system, and it is dead on as far as mileage and miles per hour compared to the spedo.

 

[Toy4x4s]

Hey Corey!

Thanks for the reply. I did go to a tire site and did the conversion. It said with the new tires it would read 65 but I'm really going 67. Albeit, not much difference.. But if it's as easy as punching some buttons to recalibrate the speedo... I'll be accurate. Allegedly you can use this device over and over. So if you change tire sizes often this would be great!

June Bennett
Cheyenne WY

 

[Mtbcoach]

The sales Mgr is a tool. I found running a true 33" tire brought the speedo about perfect w/GPS readings, almost like Mr Toyota planned it that way...

 

[1BiGGuy]

Same here. I went to the 285's and it's right on the money with the radar signs and the radar gun along with the GPS. Several on the blue room have mentioned this also over the years.

 

[Puba08]

I'm running 285 Baja MTZ's and the calibration is perfect

 

[Layonnn]

The sales Mgr is a tool. I found running a true 33" tire brought the speedo about perfect w/GPS readings, almost like Mr Toyota planned it that way...

Same.
285s/33s tend to make the speedo match a GPS for speed.

 

[BMThiker]

I think most speedo's are calibrated on the conservative side from the factory. Probably a liability thing when it comes to speeding tickets.

Upsize in tire to 285/33's made mine dead on too.

 

[Mtbcoach]

I believe there was a class-action lawsuit against Honda for doing just that, claims made that it caused for premature warranty expiration, blah, blah, blah.

I find it "odd" that off the showroom, in stock format, the speedo is off and that putting a nice set of 33's makes it spot on...

 

[Sam Stewart]

There is no way to "adjust" the speedo. I know there are some aftermarket devices that can interrupt the signal and modify it for different tire sizes. I've never seen one on a Toyota though, only jeeps and Chevys.

 

[Toy4x4s]

Wow guys... thanks for all of the good feedback... Out of curiosity I'm still gonna persue this magic device when the sales manager ans master tech come back from vacation on Tuesday. I wanna see what they tell me... I'll report back

June Bennett
Cheyenne WY

 

[Toy4x4s]

need a lift with 285/70/17's?

Those of you who are running this size tire... do they fit well, or do you really need a lift...

I was thinking OME medium in the rear, and OME heavy in front cuz I want the ARB bumper and winch... But I have not lifted it at all yet...

June Bennett
Cheyenne WY

 

[Corey]

Those of you who are running this size tire... do they fit well, or do you really need a lift...

I was thinking OME medium in the rear, and OME heavy in front cuz I want the ARB bumper and winch... But I have not lifted it at all yet...

June Bennett
Cheyenne WY

'Tis what I run.
OME medium back aft, and heavy duty up front.

It has been on there since December of 2006, and I have zero sag.
It is a basic lift with no adjustments, but it does the job.

I carry a lot of weight in my rig at all times, and the mediums are fine for the rear.

 

[Mtbcoach]

Wow guys... thanks for all of the good feedback... Out of curiosity I'm still gonna persue this magic device when the sales manager ans master tech come back from vacation on Tuesday. I wanna see what they tell me... I'll report back

June Bennett
Cheyenne WY

Pursue as you desire, the device does not exist. As mentioned above, there are aftermarket units that can be plugged int aftermarket transfer cases (Inchworm Lefty) which can be calibrated to alter the signal, fooling the ECU on the FJC.

But, if there were such a device that simply plugs into the OBDII to calibrate the ECU to the tires/wheels, I would have used it when I put 35's on as would have many, many others.

It will be an interesting conversation to hear between the tech and sales mgr, in front of a customer, please share when that happens...

 

[Toy4x4s]

Corey, how much lift do you get?

June Bennett

 

[BMThiker]

I had the same lift the first three years, and got a little over 2 inches, plus whatever the tires provided (1/2" - 3/4" or so).

 

[holmanm]

HyperTech does have a conversion module,

http://www.jegs.com/i/Hypertech/533/730108/10002/-1?parentProductId=1026990

and some sites, such as

http://www.purefjcruiser.com/hypertech-speedometer-calibrator-for-the-fj-cruiser-p-453.html

claim

Engineered to recalibrate your speedometer and odometer by just plugging it into the OBDII port under your dash, just plug in, select your tire size and/or gear ratio and in a matter of minutes you will have accurate speedometer and odometer readings again

but it really attaches inline to the back of the speedometer

http://www.hypertech.com/ProductManuals/InLine/730108_VSS Instlltn Prcdr.pdf

So it's possible but just not plug and play, some disassembly required.

 

[Toy4x4s]

How was the ride on the street... I have Goodyear Duratracs.... so stiff sidewall. I am thinking i NEED the heavy in front because i want the winch and ARB bumper.

June Bennett

 

[Corey]

Corey, how much lift do you get?

June Bennett

I never measured, but I guess 2.5".

 

[bigredmachine]

could always use this http://www.ih8mud.com/reviews/fzj80-yellowbox.php. not really plug and play but works on the 80. if the speedo reads correct than i would just leave it, dont fix whats broken.