Re:Calibration after tyre change?

Hi,

Will get my brand new Jimny in a few weeks, want to swap default Dunlop 195/80R15 with some BFG 215/75/R15 tyres. Dealer says if I do so they need to 'calibrate' the car again (at a cost of course). Other than adjusting the "wheel-rpm-to-speedometer-ratio" (if that is at all possible) because the circumference of the BFG is 1.5% larger than that of the Dunlop there's nothing much I think there's actually do be done.

Is this some BS from the dealer to get some more money out of me or is this genuine?

Cheers

Answer to my own question above:

I just got a call from the dealer and they explained the calibration has to do with the cameras for the automatic braking, they say the car needs to be on a jig and those camera recallibrated at some target, all because the car is now higher with the larger wheels.

What I personally think:

Since the BFG tyre is 1.0 cm higher than the Dunlop, it raises the car by half of that which is a mere 0.5 cm. In my opinion this 0.5 cm is utterly insignificant compared to the influence of the loading of the car: weight of occupants and luggage, roof tent and whatnot.

They charge $200 NZD for it. I say it's money thrown away, especially since I don't like the auto-braking feature to begin with.

Also: the one thing they DON'T change is the speedometer-ratio, which is the one thing I would have found logical. So my speedometer will always show 1.5% less then actual speed (but then so will my odometer).

So I say it's BS and

It's the first time I have heard of this being an issue needing adjustment? The only thing is I don't know what New Zealand is like when it comes to modifications to vehicles so it could be the local law issue?

I think most people that have fitted 40 and 50 mm lifts have managed fine with no problems without have the cameras recalibrated.

I have had no problems.

Nah, it's got nothing to do with the law.

Eventually the head of the workshop (the guy who called me back) even said that if I switch off the auto braking feature than of course it doesn't make a difference anyway. It's just something that allegedly Suzuki recommends and the dealer will be all too happy to cash the extra $200 for this 'calibration'.

It's really silly as yes, a raise of 0.5 cm makes a (insignificant) difference to the angle at which the cameras see traffic in front of the car but the weight in front or back or roof wil have much bigger influence.

In all practicality it's a non-issue.

We were discussing the safari edition on here a few weeks ago and the tyre size you are changing to is what they provide that edition with as standard, so you're not doing anything out of the ordinary by Suzuki NZs own standards.

"With a nod to its 50-year lineage, the Jimny Safari packs a punch of retro style and leading-edge performance. Elevated on Maxxis AT980 all-terrain tyres"