some questions 2013 LX570-switching from stock 20" wheels and tires to 18" TRD wheels with AT tires (1 Viewer)

[pingwrx]

I was eyeing the new GX550 Overtrail, but my LX570 is still like new even at 105K miles, so I decided to make my LX570 a little more of an off-road vehicle. First off I'm looking to swap out my 20" stock wheels and tires 285/50-20 for 18" TRD Tundra wheels with more aggressive mud+snow or AT tires. I've read through some threads in regards to bigger tires but it became overwhelming. So before I pull the trigger on new tires (I already have the rims) I have a few questions.

1) what is the largest 18" tires size I can fit without spacers lifting and rubbing? I was told 285/65-18 can someone confirm? (leaning towards BFGoodrich TA K02)
2) what about the spare tire? Can I keep the stock 20" spare tucked underneath or should I also swap it out for 18" wheel and tire? If I keep the 20" and need to use it temporarily (due to a flat) will this be OK? Since the overall diameter of the wheel will be a bit off 20" vs 18".
3) Is AHC lift necessary? Or is this just for looks?
4) Spacers necessary if there's no rubbing? or is this just for looks?
5) What do wheel offset mean and do?

Thank you in advance.

 

[tbisaacs]

Incredibly common first mod for LX owners.

275/70/18 is more or less plug and play. If you want max aggressive size, 295/70/18 isn’t much work and the spare will fit underneath. I’ve ran both sizes on my LX.

 

[doru]

If you switch, do switch all 5. You do not want to be in a place out there and have a flat or a blow out and then have to get out on the 20" just to blow that to and be stranded. There is also the need on our trucks to for tire rotation. 5 tires rotation will get a lot more miles out of your expensive tire set.

 

[doru]

AHC lift depends on where and what you do with your truck. It is not just for looks if you actually use it, not unlike any other lift. AHC is very capable system as it is. I suggest you first get your tires and then start exploring. You will find out if you need it or not.
For what wheel offset is, just search the Inet. There are lots of very good tutorials about wheel geometry.

 

[paulunm]

Love my Toyo AT3 in 285 65 18. Heavy LT tires, so they did impact MPG.

The new TRD Pro has a P metric 285 65 18 by Falken, so you could look into that if you don't want to go LT.

I did Evocourse 18x8.5 in standard offset. Don't recall the number, et45 maybe- but you can check my previous posts on topic.

 

[TimCFJ40]

The threads on "biggest tire size" are overwhelming because this question gets asked so much there are an overwhelming number of threads to read... But here are the easy answers:

1) Common bigger sizes are 275/70R18 (a bit over 33" tall and slightly narrower than stock) and 285/65R18 (Basically a 33" tall tire, same width as stock). There are the easy button choices. Very minor massaging of the fender liners and mud flaps needed at most. There are even bigger sizes that can work, but those have more potential mods and compromises. Some folks have installed close to 35" tires with minimal mods, but you'll definitely feel those in the acceleration, braking, and MPGs without further modifications.
2) My preferred option is a matching spare wheel and tire for a 5 tire rotation. But, you could replace your spare with a 20" tire with a similar diameter to your new tires, and it would work fine as a spare.
3) AHC lift is just for looks, if you do it you will also need a new alignment at the new neutral position.
4) Wheel spacers aren't necessary unless you go wider than 285. They may require additional plastic trimming since they cause the front wheels to travel in a larger arc than stock. There is some small amount of stability that could be gained with wheel spacers, and a wider stance has some minor benefits offroad, but spacers are mostly a vanity mod for most.
5) Offset determines how far the centerline of the wheel is from the mounting surface. This positions the tire further inboard or outboard from the mounting surface. Your stock wheels are +60mm offset. Lower positive offset moves the wheel farther out, so a 25mm offset (most commonly recommended offset for this platform) would cause the wheels to sit 35mm further outboard on each side, pretty close to the net effect of a 1.25" wheel spacer.

 

[pingwrx]

The threads on "biggest tire size" are overwhelming because this question gets asked so much there are an overwhelming number of threads to read... But here are the easy answers:

1) Common bigger sizes are 275/70R18 (a bit over 33" tall and slightly narrower than stock) and 285/65R18 (Basically a 33" tall tire, same width as stock). There are the easy button choices. Very minor massaging of the fender liners and mud flaps needed at most. There are even bigger sizes that can work, but those have more potential mods and compromises. Some folks have installed close to 35" tires with minimal mods, but you'll definitely feel those in the acceleration, braking, and MPGs without further modifications.
2) My preferred option is a matching spare wheel and tire for a 5 tire rotation. But, you could replace your spare with a 20" tire with a similar diameter to your new tires, and it would work fine as a spare.
3) AHC lift is just for looks, if you do it you will also need a new alignment at the new neutral position.
4) Wheel spacers aren't necessary unless you go wider than 285. They may require additional plastic trimming since they cause the front wheels to travel in a larger arc than stock. There is some small amount of stability that could be gained with wheel spacers, and a wider stance has some minor benefits offroad, but spacers are mostly a vanity mod for most.
5) Offset determines how far the centerline of the wheel is from the mounting surface. This positions the tire further inboard or outboard from the mounting surface. Your stock wheels are +60mm offset. Lower positive offset moves the wheel farther out, so a 25mm offset (most commonly recommended offset for this platform) would cause the wheels to sit 35mm further outboard on each side, pretty close to the net effect of a 1.25" wheel space

Thank you for confirming my thoughts and educating me...much appreciated!

 

[TeCKis300]

Sounds to me like you're looking for a slightly more aggressive OEM+ posture. The following IMO would make a fine balanced OEM quality setup with less compromises.

A 285/65R18 is a great size .

A 285/55R20 would be a fine closely matched overall diameter spare. Or skip the 18" wheels and just run this size all around.

Skip the KO2s. They are an ancient design and there are better all around tires including the KO3s that is out in limited sizes. A better AT tire with more well rounded qualities include the Toyo AT3s, Falken ATW3s. Those man enough as to what they really need, Michelin LTXs.

AHC lift would be awesome in moderation to keep geometries in the sweet spot. Really that's true for any lift IMO. .75-1.5". Less may be more here as it keeps AHC high with more useful down travel and better articulation.

Wheel offset ideally +35-50 for that size. The often parroted +25 is really not great for multiple geometry reasons.

 

[Ratchey]

Those man enough as to what they really need, Michelin LTXs.

 

[Cmock13]

Don't laugh, those are great tires. Used to have them on my 100, felt awesome on loose dirt roads.

 

[Ratchey]

Don't laugh, those are great tires. Used to have them on my 100, felt awesome on loose dirt roads.

I wasn't laughing at the tires. I was laughing at the comment "Those man enough as to what they really need" because it is true.
I recently bought a new set of LTX M/S2 and had been running the AT2s for about 4 years.

 

[coleAK]

Don’t do spacers.

Do a matching spare.

In my LX I run 17” in the summer (286/70-17). Just under 33”, +35 offset (although I would have liked more in line with OEM but got tired of looking for RWs) running KO2s this is my 2nd set of KO2’s (I had K02 then defender LTX m/s) they are an ok tire. Ok off road, mediocre on road, marginal in the snow, bad on ice. But they are my summer tire and I couldn’t get another set of defenders and with the shortages at the time KO2 was my only available option in the size spring of 2022…. And I rarely drive the LX in the winter. I have a matching set of 5 rims/tires. I had to heat gun drill and zip tie the front mud flaps.

In the winter I run 18” tundra take offs with Nokina Hakka 7’s (on 7th winter, will get new Hakka 10 this fall). I have a set of 4 and use a tundra steel wheel I got off Craig’s list for $20 as a spare. I run 265/60-18 in the winter for all 5 tires they are <31”.

I’m in Alaska, don’t have a ton of options. Only tire rack with ship wheels or tires up here.