Tire size question for new LR3...

[Houm_WA]

My take is that it's not good to wear tires that are different sizes, but in a pinch it can get you home; just go slow and change it when you can.

As for Costco, they are obviously trying to cover their a$$es with that policy.

Finally, I went with a Cooper size of 285/60R18. They BARELY fit in terms of diameter. In Access mode, it is REALLY tight; good thing I'm only using them for off-road purposes. I also have non-LR rims that have a different offset and I think the tires sit a little wider than stock; and so I get a bit of rubbing on the fender flare.

I'm happy with the tire size but if I had it to do over again I'd go smaller. Problem is/was that I REALLY liked the Coopers and I think that's the only 18" size they offer(ed).

 

[davez26]

Well, I bought 18" rims and put Coopers on them; I only have 4. I am not all that motivated to get a 5th. The Zeon's are 1.45" diameter larger than my 255/55R19 stock tires. While I wouldn't drive a long distance like that, I'm not going to sweat it too hard. It can get me home and from there I can get a new tire and be good to go.

Not trying to hammer you here, but traction control operates when it senses that one wheel is moving faster than another and it applies the brakes to slow it down, and
therefore gain traction. In a normal 4x4 you could probably get away w/ the smaller spare, but the LR3 is going to sense that one wheel is going faster, and then...
Just something to to think about.

 

[Houm_WA]

Dave, I'd have to research it again, but I think ETC works by sensing the torque and if there is wheel slippage, then it engages. By that logic, as long as both wheels are turning and not spinning (without traction I mean) it should be okay. It's not exactly like running a donut spare, the difference in height is an inch and a half.

...but I probably ought to look for a full-size spare and not gamble too much; that point is duly noted!

 

[davez26]

I did your homework for ya.
Technically torque is sensed, but not by any knid of "torque sensor". It is all derived from wheel speed:
From GTR:
ETC attempts to optimize forward traction by reducing engine torque or braking a spinning wheel until it regains grip.

ETC is activated if an individual wheel speed is above that of the vehicle reference speed (positive slip) and the brake pedal is not pressed. The spinning wheel is braked, allowing the excess torque to be transmitted to the non spinning wheels through the drive line. If necessary, the ABS module also sends a high speed CAN bus message to the ECM to request a reduction in engine torque. Torque reduction requests are for either a slow or fast response: a slow response requests a reduction of throttle angle (4.0L and 4.4L only); a fast response requests an ignition cut-off (4.0L and 4.4L) or a fuel cut-off (2.7L Diesel).
When the DSC function is selected off with the DSC switch, the engine torque reduction feature is disabled.
On vehicles with an automatic transmission, when the ETC function is active the ABS module also signals the TCM to prevent gear shifts.

I hope this helps!

 

[Houm_WA]

Well I think it helps confirm that we were both right, sort of...wheel speed is the trigger, but clearly the intent is to brake a "spinning" wheel. Hopefully the system is smart enough to know the difference between wheel speed deltas induced by spinning wheels with no traction, and the smaller deltas caused by having different sized tires.

The only thing to do, really, is for me to try it out and report back to the board !

 

[jwest]

Anyway, I'm planning to do the 18" wheels....then I'll bug ya'll once again about optimal tire size. I'm thinking of the 265/65/18 but maybe considering the 275/65/18 or 285/60/18. Does anyone have any opinions or input on this. There seems to be no other expert advice so I would be appreciative for some strong opinions on the matter - that is the expert advice at this point.

I would like to have a spare the same size so I'm interested to know if anyone knows that biggest size or any sizes that do fit as a full size spare underneath.

As always, thanks for the input.

-Josh

You can't run 275/65x18 on the lr3 without major rubbing at normal height and normal turning. the 265/65 already rubs a little bit at full turn and does touch a couple places at full articulation in the rear especially.

285/60 is really the size nitto terra grappler size and being wider but slightly shorter, doesn't do the rear rub as well but i think the bfg is a better tire overall.

 

[josh]

What size and tire are on your photos of the black LR3? It looks like the BFG 265/65/18...is that correct?

-Josh

 

[josh]

And so what is your opinion...BFG 265/65/18 versus Nitto Terra Grappler 285/60/18?

Thanks,

Josh

 

[jwest]

Well, I bought 18" rims and put Coopers on them; I only have 4. I am not all that motivated to get a 5th. The Zeon's are 1.45" diameter larger than my 255/55R19 stock tires. While I wouldn't drive a long distance like that, I'm not going to sweat it too hard. It can get me home and from there I can get a new tire and be good to go.

I hope you don't blow one a need the "spare" on a realt rail someday - would not be too fun with the crap doughnut or even a full size 19" goodyear..... it's only $500 or less to have a proper matching 18 and tire.

 

[jwest]

And so what is your opinion...BFG 265/65/18 versus Nitto Terra Grappler 285/60/18?

Thanks,

Josh

I've driven both on the lr3, the terra looks great but the bfg just seems more substantial - even if only a little more.

yes on the size. i wanted the most heigh posible though and the bfg gave me just a touch more than the 60 but the 60 is wider. the nitto was ver ytight behind the upper edge of the control tower/arms behind the top of the tire though - too close for my comfort but i have seen it just fit on some lr3's so some must come off the line with more or less clearance. i think the 265/65 might even allow a snow chain though so i wanted the most flexibility as well as the best tire.