New Gear Ratio W/ Larger Tires? LR4

ticklemenono

New member
I hope I'm not beating a dead horse... But, from what i gather the stock 2012 LR4 tire size was 255/55/19 I am currently running 285/60/18 which is about an inch worth of diameter difference. I am looking to move up to (undecided) either: 265/70/18, 285/65/18, 275/70/18 which will be about a 3 inch diameter difference from stock.

My questions is, with this increase in tire size should I be concerned about the gear ratios of my 2012 LR4? If anyone with experience in this can provide insight it will be greatly appreciated.

Thanks!
 

unseenone

Explorer
Others have done this, but your gear ratios are limited, and the one you have is as good as it gets.

In short, I wouldn't be to concerned about gear ratio. Here is a neat calculator to show you the differences of various tire and wheel combinations..

255/55/19 vs 285/60/18

255/55/19 vs 285/65/18

You'll need to think about how not to tear up your fender wells with the taller tires.

You "might", I am not sure, be able to adjust the speedometer via an IID tool, I'm not sure on the 4.

I hope this helps
 

Jwestpro

Explorer
I am looking to move up to (undecided) either: 265/70/18, 285/65/18, 275/70/18 which will be about a 3 inch diameter difference from stock.

My questions is, with this increase in tire size should I be concerned about the gear ratios of my 2012 LR4? If anyone with experience in this can provide insight it will be greatly appreciated.

Thanks!

Nobody else is really concerned with the gears.

However, I hope you aren't planning on these size with a stock vehicle...and "rods" don't count as a band-aid.

FYI, 285/65 will be 32.5- 32.7 but 275/70 will be 33"+ and would be very "interesting" even after the mods to both front and rear wheel well/ fender liners. Without the standard physical mods, you WILL be scrubbing the heck out of the tires. I don't really even care about the body parts but I wouldn't want to be ripping the hell out of the tires senselessly.

The 285/65 could easily rub the upper control arm too cutting into the tire depending on the specific tire used. The tightest moment will be at extension, not compression, so it will happen without you thinking it would if only testing the clearances at normal height in a tire shop. On vehicles with IFS, lots of things happen at various angles and strut extensions.
 

zelatore

Explorer
Nobody else is really concerned with the gears.

However, I hope you aren't planning on these size with a stock vehicle...and "rods" don't count as a band-aid.

FYI, 285/65 will be 32.5- 32.7 but 275/70 will be 33"+ and would be very "interesting" even after the mods to both front and rear wheel well/ fender liners. Without the standard physical mods, you WILL be scrubbing the heck out of the tires. I don't really even care about the body parts but I wouldn't want to be ripping the hell out of the tires senselessly.

The 285/65 could easily rub the upper control arm too cutting into the tire depending on the specific tire used. The tightest moment will be at extension, not compression, so it will happen without you thinking it would if only testing the clearances at normal height in a tire shop. On vehicles with IFS, lots of things happen at various angles and strut extensions.

I'd agree with the above.

I run 275/65-18 Duratracs on my '07 and had to do some work to both the front and rear. I also helped a friend sort out the same size Cooper AT/3s on LR3 wheels w/spacers on her LR4 and had to do more mods with it than on my LR3, largely because the spacers changed the position of the front tires within the wheel wells when turned.

I am considering going to a 275/70-18 mud terrain tire this winter, but even with mods I don't know if I can make it work. I 'think' I can, but I haven't actually made measurements yet. I do know I'll have to mod the struts to increase the bump stops at a minimum.
 

Jwestpro

Explorer
Regarding 275/70x18 33" tire fitting: I do know I'll have to mod the struts to increase the bump stops at a minimum.

Why the bumps stops? I don't think so necessarily. I've used my LLAMS tool to drop the vehicle as low as possible and the scrubbing it not too crazy but it is lots of contact against the fender liners. What I'm getting at is altering fender liners where needed vs changing bump stops which would start to reduce range of articulation.

(at maximum drop, the warning comes on and it wants to be raised but what's cool about the LLMS special red button is that it "locks" the system such that the vehicle won't lift up even though it thinks it needs to)

I've mainly tried this full drop with spacers which make the fender liner situation worse. No spacers should keep the tire tucked where there's more liner space left up top - maybe.

My bigger concern is at the 3 and 9 o'clock positions of the tire/fender gap. The rear 3 will get really tight at those spots and with the Kaymar, using oem mud flap as the gap filler, it's even less space than factory rear bumper without mud flaps. Kaymar did a really weird thing there that basically requires the bulky stupid oem flap. In fact it's not even a "flap" but too rigid to move at all. I'd rather have it gone and use replaceable thin flat flaps like on Defenders or my D1

Up front a 33" will get right into the ARB bumper which houses some things right in that area like washer fluid or something. The next to impossible spot would be where we've already removed frame steel at back of front wheels.
 

Jwestpro

Explorer
Jwestpro do you run LLAMS and GAP, or just LLAMS?

Are you crazy? ;) both of course! Really perfect as a combined approach.

No seriously, I use the GAP just for other purposes now. I don't use the GAP at all for height anymore because there's basically zero need to with the much quicker and locking into max high or max low feature of the LLAMS. I actually run around in town, like under 50mph, in +30 mm often to help wear the tires more flatly as our independent suspension camber likes to wear out the inside edges faster on normal height. This also gives me a little better feeling wearing them out worse on curvy mtn roads where it's more stable to drop into -20mm for those sections.

The LLAMS is just SO convenient and quick. For example, need to drop to the lowest height for a city garage? It takes 3 seconds to switch to -20mm, then press the red lowest button for another -20 or so. While waiting in traffic before the entrance, as you enter use the factory lever to drop again if needed. The red locking button will keep it bottomed out as you creep around in the garage. Now with a Hannibal rack and also rear Hannibal awning, I can still clear under 80" no problem. It's lower than that but I can't recall exactly right now.
 

Forum statistics

Threads
188,632
Messages
2,908,122
Members
230,800
Latest member
Mcoleman
Top