Need to some help on this one, from people that have lifted, or fitted a bit larger tires on their W163’s. I am not looking for something huge in a lift/tire but I want a bit more ground clearance, and a bit more suitable tire for the many unpaved roads here in BC Canada. There are a few threads on here about this, but most of them many years ago, but I thought I start one with my questions here.

As a start, right now I have the stock Pirelli 285/50/R18 on my ML55 which with the proper (inch) conversion/diameter is a 29.5 tire. There is plenty of room from the top of the wheel to the wheel frame on the car. I have been looking at tires, and from both a cosmetic and performance standpoint I want to fit the 285/60/R18 BF Goodrich All-Terrain T/A KO2.

Using a tire calculator, https://tiresize.com/height-calculator/ going from 50-60 would make this a 31.5 diameter tire. That is a 2.3 increase from the stock tires I have on now. I went down to my “tire guy” today and wanted to place the order, but he told me to investigate a bit more and gave me a few things to double check before. I mentioned I frequently use this forum, and have gotten great help here before, so here are my questions/concerns/advice.

1. Would this tire fit without a lift? If not, I have spoken to a company in Germany called ORC, and they make a rear +1 inch lift kit, but its $300 dollars, but that would lift the back, as I understand the front can also be raised about +1 inch or so via torsion bar adjustments.

2. My “tire guy” mentioned my ML “might” have electronic steering, which would be messed up with a larger tire? He also said the transmission could “blow” because of the different new ratio not programmed into the computer. Could that programming be done? Or is it needed?

3. Would the odometer be off? Could it be corrected, is it a bit deal?

4. I have included one image below from another user on this forum, I sent him a message directly a few weeks ago but haven’t heard back. He wrote in the post that he did a torsion bar “indexing” is this the same as adjusting the torsion bars? Or a different thing all together? The link to that thread is https://mbworld.org/forums/m-class-w...-lift-m-2.html

More on that thread I mentioned in point 4. This is what he wrote on there
”Kurts, Justin, Idotm, Thanks to all of you for contributing to this lifting of the ML W163 series. Yes, the Torsion indexing works. I've replaced the Torsion Bushings on driver and passenger sides, indexed the Torsion to about 3mm initially it was at 3.8 mm with the factory 17" wheels and 275/55R17 tire. Now that the Torsion indexed to 3mm, it raised the vehicle by 3" front and back and put new tires BF Goodrich KO2 275/70/R17 without any rubbing issues. Works and looks great.”

According the same tire diameter calculations, his tire diameter with the BFG KO2 he put on (275/70/R17) would be 32.2 that would be larger than the tire I am trying to fit “31.5” and he did it without mentioning any transmission/steering issues”

Might have a few more Q’s, but would greatly appreciate any help from people that have done this. Thank you!

(including the image below from that thread, and sort of what i am trying to accomplish)

 

Anyone with some comments that has fitted larger tires potentially a rear lift?

I reached out the ORC (the company that makes the spacers for rear) and they thought that the 285/60/R18 would be too wide for the W163, However, i am using stock 285/50/R18 now, wouldn't the first number "285" be the width, in other words same width as the tire i want to get?

ORC's reply below.

"Unfortunately the 285/60R18 are too wide and too big. We would recommend to mount maximum the size 265/60R18."

 

You are correct. The 1st number is the width (285) the second number is the height (50 or 60) and the third number is the rim size.
That said a 50 series tire is not as tall as a 60 series tire.
Hope this helps you.

 

Fitting the 285/60 on my ML the increase in diameter would be 57 mm or 2.3 inches. But the ORC lift would raise the back with 30 mm and then i could match in the front with the torsion bars.

So in essence, with the large tire, the lift and torsion adj. Space wise, top of tire to chassis i would have 27 mm or 1.12 inches less than now with my 285/50 tire on there?

Anyone out there that has used this tire or similar diameter / lift on their ML's?