Best wheel and tire size for GQ Y60 Patrol and in general: 15”, 16” or 17”

[symmetry4wd]

So guys, just spit balling some ideas here, any input would be nice:

I am mainly talking about a GQ, but any platform applies:

15” wheels and tires - isn’t it every 4x4 users dream to have the smallest wheel possible, with the biggest tire/side wall possible?

- Bigger/longer footprint when aired down
- softer more supple ride off-road over rough terrain, even on-road with humps and bumps
- cheapest option, at least new, in terms of cost
- some nice size options
- Interestingly enough, lighter in most cases than comparable sized 16 or 17 inch tires (as far as I can tell it’s from the comparably lower load rating )
- looks the best to many (big bulging tires, small wheel), basically makes the tyre look bigger than it is

What’s not to like right?

Some of the negatives would be:

- becoming more difficult to find as new 4x4s run 16 and more common 17 or 18” wheels ()
- lower load and speed rating than most 16 or 17” options
- running a 15” wheel limits your options for upgrading brake calipers and disks if that is something you are considering on your rig
- more sidewall flex and “wallowing” ride on-road (not an issue in my mind, these aren’t sports cars)

16” wheels and tires:
The “go to” size for many. I’m personally not a fan in the current state of things.

- very common size for 4x4’s, readily available
- good balance between the ratio of wheel to tire/sidewall, decent side wall heights without needing a massive tire
- good balance regarding size of wheel to accommodate good brakes

Pretty good all round but doesn’t excel in any particular areas. All rounder

Negatives would be:

- expensive compared to 15” wheels and tires, and same as 17’s
- not many size options for 33’s, 35’s & even 37’s, at least locally
- heavier than 15 or 17” tyres for comparable sizes, surprisingly
- a bit of a jack of all trades master of none in my opinion (great all rounder, but maybe not as focused as I may like, splitting hairs here maybe, the price gets me though, being one of the most popular sizes, but R1000+ a tire more than 15’s and same price as 17’s)

17” wheels and tires:
Taken over as the new “most popular size” whereas 16’s use to be the go to.

- best current availability to my knowledge and research
- best availability and variety of wheels, and in a lot of cases tires
- good space and clearance for brake upgrades or running big brakes
- many size options (and for the crazies, 37’s, 38’s,39’s, 40’s, 42” options)
- on par with 16” prices
- same tire weight as comparable 16’s
- will continue to be longer supported than the somewhat aging 15’s and 16” options
- high load and speed ratings
- best road manners (don’t care)

Quite a few positives, but the negatives would be:

- unnecessarily large wheel size for most applications, where braking is concerned, and unnecessary when you could have more tire than more wheel
- wheels more expensive than most 16’s and definitely more than 15” wheels
- wheel weight
- tires weigh more than 15’s
- depending on your tire choice it could leave you with very little sidewall
- less footprint than comparable 16 or 15” tires

We won’t get into 18,19 and 20” tires, 18’s you could argue still have their place on an off-road vehicle, but any bigger I just personally can’t see the point unless you are running 37”+ tires.

Maybe this is long winded, but I at least got to get my thoughts down.

Personally after looking at it, boiling down to price and performance, I am heavily leaning towards 15” for my application when off-road performance is one of the highest priority’s, it seems to make sense to me. Also not having disposable income, cost is also a factor when pursuing the performance I would like. The Gq came with 15’s, and many other 4x4’s wish they could run 15’s, maybe something is to be said for that.

I am not saying any of the above options is right or wrong, I’m just sharing thoughts. Any of your experiences and thoughts are welcome.

Just a quick food for thought comparison:

33x12.5 R15 BFG KM3 60lbs weight, call it R5300.00
229mm sidewall height

285/75 R16 BFG KM3 65lbs weight, call it R5700.00
213mm sidewall height

285/70 R17 BFG KM3 67lbs weight, call it R6500.00
201mm side wall

(Seems like 17’s loose this particular one)

To note a 33x12.5 R15 has the same sidewall height as a 35x12.5 R17

Tired now….

[Peter Connan]

I'm tired just from reading it.

But here are a couple of thoughts:
1) You drive a GQ. To fit anything larger than 33", you either need to lift it quite a lot , or climb in with an angle grinder. Also, tires wider than about 10.5" will limit flex at the rear unless you have done one of the above-mentioned mods and run rims with increased offset.
2) You drive a GQ. Why is speed rating important? I managed to get 160 out of mine just once, down one hell of a downhill.
3) Weight is the enemy in all forms of driving, including 4 wheeling. Keep the vehicle light and forget about the weight rating too.
4) Despite the above, I have recently seen several people claim that, for rock crawling specifically, a higher percentage of un-sprung weight is better as it lowers CG and keeps the wheels on the ground better at very low speeds.
5) The standard gearing on your vehicle is well suited to tires of up to 33". After that, you really want to go lower. The only lower options available are 4.35 and 4.66. Both are expensive (in proportion to the vehicle cost). 4.66 is fairly well suited to 37". Anything bigger than 37" becomes an issue in my opinion.

But I will never deny that the bigger the tire, the better the off-road performance, and I would put 54" tires on my car tomorrow if I could afford it. The cost of that would include a second vehicle for on-road use.

For general use (road driving, overlanding and 90% of 4x4 trails), the best tire size for a GQ I have ever tried was 255/85R16. A 33" tire 10.5" wide. Contrary to popular belief, a narrow tire is better in sand than a wide one, especially when following other vehicles. I also found it excellent in mud, found that it was less prone to sidewall damage and so forth. Unfortunately they are pretty hard to find. 33x10.5x15" would probably be even better but they are virtually unobtainable here, and extremely expensive when you can find them.

I have settled on 285/75R16 as the best compromise for a relatively standard GQ. They did reduce my flex by about 100mm compared to the 255/85s but at least I stand a good chance of finding a replacement if I lose one on a long trip. 33x12.5x15's are a close second but will rob even more flex.

If you specifically want to build a trail rig, and are prepared to spend the money, then haul out the grinder, cut away the arches, put 4.66 gears in the diffs and lower ratios in the transfer case and stuff 37" under it (or do it properly, put a doubler or an 3-speed Atlas transfer case in and go all the way to 40"). Once you are up to 37", I don't think rim size matters that much anymore. Either of the 3 options will work.

[symmetry4wd]

I'm tired just from reading it.

But here are a couple of thoughts:
1) You drive a GQ. To fit anything larger than 33", you either need to lift it quite a lot , or climb in with an angle grinder. Also, tires wider than about 10.5" will limit flex at the rear unless you have done one of the above-mentioned mods and run rims with increased offset.
2) You drive a GQ. Why is speed rating important? I managed to get 160 out of mine just once, down one hell of a downhill.
3) Weight is the enemy in all forms of driving, including 4 wheeling. Keep the vehicle light and forget about the weight rating too.
4) Despite the above, I have recently seen several people claim that, for rock crawling specifically, a higher percentage of un-sprung weight is better as it lowers CG and keeps the wheels on the ground better at very low speeds.
5) The standard gearing on your vehicle is well suited to tires of up to 33". After that, you really want to go lower. The only lower options available are 4.35 and 4.66. Both are expensive (in proportion to the vehicle cost). 4.66 is fairly well suited to 37". Anything bigger than 37" becomes an issue in my opinion.

But I will never deny that the bigger the tire, the better the off-road performance, and I would put 54" tires on my car tomorrow if I could afford it. The cost of that would include a second vehicle for on-road use.

For general use (road driving, overlanding and 90% of 4x4 trails), the best tire size for a GQ I have ever tried was 255/85R16. A 33" tire 10.5" wide. Contrary to popular belief, a narrow tire is better in sand than a wide one, especially when following other vehicles. I also found it excellent in mud, found that it was less prone to sidewall damage and so forth. Unfortunately they are pretty hard to find. 33x10.5x15" would probably be even better but they are virtually unobtainable here, and extremely expensive when you can find them.

I have settled on 285/75R16 as the best compromise for a relatively standard GQ. They did reduce my flex by about 100mm compared to the 255/85s but at least I stand a good chance of finding a replacement if I lose one on a long trip. 33x12.5x15's are a close second but will rob even more flex.

If you specifically want to build a trail rig, and are prepared to spend the money, then haul out the grinder, cut away the arches, put 4.66 gears in the diffs and lower ratios in the transfer case and stuff 37" under it (or do it properly, put a doubler or an 3-speed Atlas transfer case in and go all the way to 40"). Once you are up to 37", I don't think rim size matters that much anymore. Either of the 3 options will work.

Hi Peter, thanks for your thoughts, I always appreciate it!

1) Definitely agree here. I think 33", 2-3" lift, so pretty close to standard is where I would like to keep my GQ for the time being.
2) Speed rating is definitely not important to me at all, I drive 100/110, 120 at a push briefly. I was just adding it to the comparison.
3) 1000%, weight (less) is the best performance modification for any vehicle, for most applications, very important to me!
4) Very interesting, makes sense.
5) I would like slightly lower gearing anyway for my preference, Transfer reduction gears would be great but so expensive. Ring and Pinion slightly cheaper but still expensive

I'm not building a specific trail rig, but want my car to be as capable as possible and not have to hsy away from challenging obstacles.

I agree that the 255/85R16's seem like the best all rounders, but like you said, they are just so scarce.
Skinny > wide. Thin tyres are better than wide in most off-road situations, agreed.

My likely 2 options are the 285/75/16 on a 0 offset 16x8j wheel, or 33x12.5R15 on a 15x8j -28 offset.
Would these allow a similar amount of flex before rubbing?

[Peter Connan]

I suspect 33 x 12.5's on a -28 offset will rub on the outside of the tire/inside lip of the arch.

According to the Auzzies, the ideal offset for 285's is -22.

I suspect the need to shy away from challenging obstacles has more to do with underbody protection than with tire size.
By changing tire size, you are just shifting the goal-posts. There will always be obstacles too large for one's vehicle.

[symmetry4wd]

I suspect 33 x 12.5's on a -28 offset will rub on the outside of the tire/inside lip of the arch.

According to the Auzzies, the ideal offset for 285's is -22.

I suspect the need to shy away from challenging obstacles has more to do with underbody protection than with tire size.
By changing tire size, you are just shifting the goal-posts. There will always be obstacles too large for one's vehicle.

I do trust the Aussie's experience when it comes to Patrols.

That is also my thought in terms of protecting all of the vitals, I think 33's will be enough for 90% of what I would like to do, and just make sure the car is fully protected against damage.

That is some wise insights about shifting goal-posts, good food for thought.

[Tinus lotz]

285 75 16 is the best all rounder at this stage ...