Thinnest tire on 200 series

[40Man]

Good eye. She's a 27FB Ocean Breeze that I've spent lots of time modifying thanks to the also great community there. Thanks for sharing the link and I'm enjoying the frame off restoration pics!

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The load derived inflation pressures are a solid baseline from which to start from. I absolutely agree with you, and it's a point that I also reiterate. Pressures can and should be further adjusted for other factors. The cross data tells us it's very likely that the LC factory pressures were tailored up from base load pressures for things like Dunlop Grandtrek AT23 tire traits, tire wear, sidewall rollover, handling, etc.

Strict load inflation tables tells me to use 35psi for my 35x12.5s. For my particular Toyo ATIII tire fitment, handling feedback (calibrated from my track days) tells me that it's not enough pressure to keep the sidewalls from rolling over under cornering for my driving style. To your point, I tailor my pressures up a few PSI from there. When I tow, even though tire pressure already more than meet necessary load ratings, I still go up a few PSI from that. Yet I'm not afraid to cruise highways at say 30 PSI when I'm completely unladen transiting between off-road segments, because load derived base pressures are good up to the full chassis load, max speed, on the hottest of summer days.

A potential methodology for any fitment would probably be the start with the heavier LX derived pressures as a safe min load basis for the 200-series chassis. Then tailor up from there. Stiffer carcass tire models or wider wheel and tire fitments may not need anymore pressure. Taller narrow tires may demand more. More armor and weight, may want more pressure. Etc.

One point of clarification, for the 20 inch LX wheels (didn't analyze the 21 inch option), Toyota recommends 33 PSI on what I believe is a 112 rated Michelin tire (load capacity of 2,315 lbs at 33 psi per Toyo Load Index Table for a 112 load tire). The Land Cruiser recommends 33 PSI on a 116 load rated Grandtrek (load capacity of 2491 lbs per wheel per Toyo index). Both cars have the same GAWR and GVWR, but the Lexus carries more weight stock, yet the LC has the heavier recommended load index..

So it seems to me that the LX tire load and pressure (112 load index and 33 psi for standard load tire) is our baseline, and conservatively we should not go below it on the LX or the LC. And if you run the stock p rated LC tire on your LX (285/60R18), it would seem logical to start with the LC recommended inflation of 33 psi. It will provide a better number than trying to lower the PSI to match the load rating the stock LX tire comes with.

SO while logically it may seem if anything, the heavier stock LX should have higher derived loads/higher psi recommendations for the lower load tire, it is actually lower than the LC.

And also:

What is the land speed velocity of an unladen Land Cruiser?

 

[grinchy]

There were some posts somewhere on mud last spring with anecdotal evidence that skinnies were working better than wides on a wet rocky slope. But the vehicles were different (jeep vs Toyota) and it seems something else was different too. Maybe tire pressure.

 

[bloc]

@VooDoo2 what is the preferred setup in Australia? I get the impression many of the builds there are no-nonsense and function over form.

 

[gaijin]

One point of clarification, for the 20 inch LX wheels (didn't analyze the 21 inch option), Toyota recommends 33 PSI on what I believe is a 112 rated Michelin tire (load capacity of 2,315 lbs at 33 psi per Toyo Load Index Table for a 112 load tire). The Land Cruiser recommends 33 PSI on a 116 load rated Grandtrek (load capacity of 2491 lbs per wheel per Toyo index). Both cars have the same GAWR and GVWR, but the Lexus carries more weight stock, yet the LC has the heavier recommended load index..

So it seems to me that the LX tire load and pressure (112 load index and 33 psi for standard load tire) is our baseline, and conservatively we should not go below it on the LX or the LC. And if you run the stock p rated LC tire on your LX (285/60R18), it would seem logical to start with the LC recommended inflation of 33 psi. It will provide a better number than trying to lower the PSI to match the load rating the stock LX tire comes with.

SO while logically it may seem if anything, the heavier stock LX should have higher derived loads/higher psi recommendations for the lower load tire, it is actually lower than the LC.

You are exactly right - and that is what I have been saying all along.

I think we can all relax now and watch football.

 

[VooDoo2]

@VooDoo2 what is the preferred setup in Australia? I get the impression many of the builds there are no-nonsense and function over form.

Generally the biggest that will fit. Some guys are getting into 37's andn1 guy has 40's

 

[scottm]

Generally the biggest that will fit. Some guys are getting into 37's andn1 guy has 40's

Sounds like Iceland Cruisers.

 

[bloc]

Generally the biggest that will fit. Some guys are getting into 37's andn1 guy has 40's

On 200s? With KDSS? And are they usually stock width or greater, or going skinny?

 

[VooDoo2]

On 200s? With KDSS? And are they usually stock width or greater, or going skinny?

I run 35/12.5/18's on a 18x9 Rim with +20 offset (method 305NV) Only real mods other than king suspension is UCA's and body mount chop

 

[ryanCA]

I have the Falken Wildpeaks in LT255 /80 R17. I don’t drive it like a sports car so no complaints about the handling on road. They are bit lighter than comparable wider tires, but I doubt it makes much difference. I got them mostly because I love the LT255/85R16 BFG KM2s on my 4Runner. But when shopping for the 200, the Falkens were on sale and the BFGs most definitely were not ($190 vs $275), so I figured I’d give them a try. They were great for 6 weeks of camping/offroading in AZ/UT/CO earlier in the fall.

Here’s an argument in favor of narrower/taller tires for offroad from Scott Brady.

for my next set I am going down from my 275 to a 255.

How are you liking yours still?