Land Cruiser Tire Upgrades?

[RideWithYanu]

When is a chalk test not the conclusive answer for tire pressures?

When I first put on my Method MR703s and Toyo OC ATIIIs, the tires were aired up to 36/37psi. I thought the ride was pretty rough. I looked to the Tire Pressure Calculator to get an idea of where the PSI should be. Since I went with P Metric Standard Load (NOT E or C) 117 ATIII's, it spit out 28psi.

I posted that here. @Blue Bear responded and recommended 32PSI based on the Load Inflation Tables. And also recommended a chalk test. I performed the chalk test and found that 25PSI Cold, was the best PSI to get full coverage across the tread. This drastically improved the ride quality as well. It did add some bowing to the sidewall and looked air'd down. I figured this was fine. I've kept it at 25PSI for past 6 months (note I've only put about 1,000 miles on the car in the last 6 months, short commute).

Until I came across this post...



It got me thinking, am I stressing my drivetrain by having the tires aired too down? I've never had any issues, and the transmission temps are always fine. Rationally I figure that it can't be more stress than 35" tires and lots of extra weight (which plenty of users seem to be doing with no issues). But I decided to air them back up to 32 today just in case. And immediately the ride quality was worse again. I can feel every little thing on the road, stopping distance seemed to be worse too.

Is there a lower limit to the chalk test?

You’re not stressing your transmission but you may be degrading your fuel efficiency, if that’s something that bothers you.

 

[KWLC250]

Thanks for posting this!!!

My pleasure. The chalk test seems to be the go to recommendation for tire pressures. And I see a wide range of recommendations across Tire Brands, Load Indexes, Tire & Vehicle sizes across the internet.

The Tire Pressure Calculator isn't consistent with the aforementioned Load Inflation tables. I'm not sure what calculations the Calculator based it's recommendations on. But I've also noticed different recommendations based on the Load Inflation Tables, which confuses me as well.

My mode,l '25 LC Premium, came with the Michelin 265/70/18 SL116 load index. The door placard states 33PSI for 265/70/18 but doesn't mention a load rating. And the load ratings on some of the other OEM tire options were different, but seem to all suggest 33PSI on the door placard.

• 265/70R18 (LC/FE Trim): 116S Load Index (2,756 lbs per tire)
• 265/60R20 (Premium Package): 112H Load Index (2,469 lbs per tire)
• 245/70R18 (1958 Trim): 110H Load Index (2,337 lbs per tire)

I realize there are weight differences between the models. But as you see here the Premium could have come with the 20" tires with a 112 Load Index or the 18" tires with a 116 Load Index. Making it even more confusing to determine the correct PSI based off the door placard and the Load Inflation Tables alone.

 

[KWLC250]

You’re not stressing your transmission but you may be degrading your fuel efficiency, if that’s something that bothers you.

I can live with being at the gas pump more often. As you can see I live on a 2x4 mile island and in a year I've only put ~3500 miles on the truck. Just want to make sure I'm not over-stressing anything.

I'm about to head in for the one year service appointment. And I'm getting ready to pull the trigger on a lift. So I'd like to note any issues or concerns at the appointment so they're noted before I do the lift. So the lift doesn't take the blame if I need to do any warranty work. So that's had me really paying attention to the truck I guess. And I have noticed something I can feel in the steering wheel, that I can't really describe. But I can definitely feel the drivetrain through the steering when under power and deceleration/coasting . Probably normal and been there all along, but after I came across the post I linked above it had me thinking. My wife also has an LC. Hers is an LC LC Base. I can feel the same feeling, maybe not as exaggerated in her car. Again likely paranoia...

 

[RideWithYanu]

I can live with being at the gas pump more often. As you can see I live on a 2x4 mile island and in a year I've only put ~3500 miles on the truck. Just want to make sure I'm not over-stressing anything.

I'm about to head in for the one year service appointment. And I'm getting ready to pull the trigger on a lift. So I'd like to note any issues or concerns at the appointment so they're noted before I do the lift. So the lift doesn't take the blame if I need to do any warranty work. So that's had me really paying attention to the truck I guess. And I have noticed something I can feel in the steering wheel, that I can't really describe. But I can definitely feel the drivetrain through the steering when under power and deceleration/coasting . Probably normal and been there all along, but after I came across the post I linked above it had me thinking. My wife also has an LC. Hers is an LC LC Base. I can feel the same feeling, maybe not as exaggerated in her car. Again likely paranoia...

Conch Repub - lived there for a couple years long ago!

 

[KWLC250]

Conch Repub - lived there for a couple years long ago!

"We seceded where others failed!" Been here 20 years, married a conch and produced one

 

[ultane]

…And I have noticed something I can feel in the steering wheel, that I can't really describe. But I can definitely feel the drivetrain through the steering when under power and deceleration/coasting . Probably normal and been there all along, but after I came across the post I linked above it had me thinking. My wife also has an LC. Hers is an LC LC Base. I can feel the same feeling, maybe not as exaggerated in her car. Again likely paranoia...

I’m under the impression that there is no physical connection between the steering wheel and the front tires in our LC’s… ??? …that the steering mechanism is ‘fly by wire’… so I’m not really sure what the possibilities are that you could be ‘feeling’???

 

[KWLC250]

I’m under the impression that there is no physical connection between the steering wheel and the front tires in our LC’s… ??? …that the steering mechanism is ‘fly by wire’… so I’m not really sure what the possibilities are that you could be ‘feeling’???

I can definitely something in the steering. The LC250 uses an electric power steering assist. But there still should be a mechanical linkage. Not a true "fly by wire". The Mazda RX-8 used a similar system. I raced a RX-8 for a few years, and with the EPS deactivated you could still steer the car, just without power steering assist. As you can probably turn the wheels on the LC250 without power, I'm guessing there's a mechanical linkage.

Here's what google AI said;

The Toyota Land Cruiser LC250 is the first in the Land Cruiser lineup to feature an Electric Power Steering (EPS) system, which consists of several key components working together to provide smooth and responsive handling.

Key Components
The LC250's steering system includes the following main parts:
St Charles Toyota +1

• Steering Wheel: The primary input device used by the driver to control the vehicle's direction.
• Steering Column: Connects the steering wheel to the steering gear assembly and houses components like universal joints and column bearings.
• Electric Power Steering Gear Assembly: This central component uses an electric motor (instead of a hydraulic pump) to provide steering assistance, converting the steering wheel's rotation into the lateral movement of the wheels via a rack-and-pinion mechanism.
• EPS Control Module (ECU): This electronic control unit receives input from various sensors (like the torque sensor which measures how much the driver is turning the wheel) to determine the amount of power assist needed.
• Tie Rods: These link the steering rack to the steering knuckles at the wheels, transmitting the steering force.
• Steering Knuckles: These are the pivot points where the wheels are attached and which turn to steer the vehicle.
• Stabilizer with Disconnection Mechanism (SDM): The LC250 also features a switch-operated function that can lock or unlock the front stabilizer bar, improving wheel articulation and comfort for off-road driving and enhancing stability on-road.
  トヨタ自動車株式会社 公式企業サイト +7

The EPS system is designed to reduce kickback from rough surfaces and improve maneuverability at low speeds compared to traditional hydraulic systems.

System Layout and Main Components
The LC250's EPS system typically follows a rack-assist or column-assist design where electronic signals replace hydraulic pressure to provide steering force.
Toyota Australia +4

• Electric Steering Rack Assembly: This is the core mechanical unit. It contains the electric motor that provides the torque needed to turn the wheels.
• Torque Sensor: Located within the steering column or rack, it detects the force and direction applied by the driver to the steering wheel and sends this data to the ECU.
• Electronic Control Unit (ECU): The "brain" of the system that processes sensor data (vehicle speed, torque, steering angle) to calculate the exact amount of motor assistance required.
• Steering Column & Intermediate Shaft: These connect the steering wheel to the rack. In the LC250, these are designed to work with the electric motor's torque delivery.
• Stabilizer with Disconnection Mechanism (SDM): A unique LC250 component that allows the driver to electronically "free" the front stabilizer bar for better off-road articulation, which is integrated into the overall steering and chassis control.
  トヨタ自動車株式会社 公式企業サイト +4

 

[pdizzle]

Has anyone had any issues with heavier tires and the US spec 2.4L iForce Max engine? I know gas mileage can (and likely will) take a hit. I'm more concerned with messing up the performance and making the engine feel sluggish or straining the drivetrain. The tire combo (275/70R18 Toyo AT3's with factory 18's) is only an estimated (I'm using figures I've scoured of the web) 6lbs heavier than the stock 20" inch rim and tire combo (at 80 lbs). But the Toyo is significantly heavier than the stock Michelin ATX tires (53lbs and 38lbs respectively) that are on there now.

Mine feels more sluggish with KO threes on it then my friends does with the stock tires. Smame size

 

[BigSherm]

So back in March I got a wheel / tire pack 275/70/18 Nitto Terra Grappplers G3 and Method 8.5 inch wide wheel with a 40 offset.

They have fit perfect , flush, no rubbing at all. It has been all good, except when I got them, I went with a smaller 275 instead of 285 because I thought I may want to go up in a size.

Well now that has time has come. I have just ordered a set of 285/70/18 Toyo Open Country AT3’s. They should be here Monday.

I’m going to put one of my Nitto’s 275 on my spare as well.

I believe this 285 upgrade will have a slight more poke than my current tire package which is what I want. I went with AT3 over the G3’s based on what the poke will reveal once installed. Thoughts ? I will post pics once installed

 

[DubDub]

So back in March I got a wheel / tire pack 275/70/18 Nitto Terra Grappplers G3 and Method 8.5 inch wide wheel with a 40 offset.

They have fit perfect , flush, no rubbing at all. It has been all good, except when I got them, I went with a smaller 275 instead of 285 because I thought I may want to go up in a size.

Well now that has time has come. I have just ordered a set of 285/70/18 Toyo Open Country AT3’s. They should be here Monday.

I’m going to put one of my Nitto’s 275 on my spare as well.

I believe this 285 upgrade will have a slight more poke than my current tire package which is what I want. I went with AT3 over the G3’s based on what the poke will reveal once installed. Thoughts ? I will post pics once installed

Yes, the 10mm difference between a 275 and 285 (if no other factor changes) will be a 5mm (0.185”) increase in poke at the tread patch. You will likely see more visual poke due to the increased sidewall height (0.28”/7mm) and proportional bulge. My 285/65s bulge quite a bit, so those 70s should look fat (and phat ).

 

[TraumaPA]

I went with the Falken Wildpeak AT4w in 35-11.5-r18 load range C because of the 62 lb weight. The same tire in 285-75-r18 load range E is 78 lbs. My setup drives fantastic.View attachment 56925

Does this tire fit in the spare location?

 

[Area 51]

Watch the weight.
Big deltas size and types compared.
Even amongst the same brand.
More weight = less mileage, more brake pad wear, greater stopping distance, poorer acceleration, heaver and greater ply side walls better if you air down or need the side wall cut and scuff resistance.
Much to consider depending on your use case.
Whatever you get get top rate tires. You have about an inch between you and freeway at speed.
35', there is a mode that is simple, watch the Ed Brown Toyota video.

 

[ultane]

Does this tire fit in the spare location?

Welcome to the asylum.

Please don’t quote me on this, but I think 275’s fit, but most 285’s do not. Fear not, I’m sure members will be along shortly to correct me if I am wrong.

 

[BigSherm]

Welcome to the asylum.

Please don’t quote me on this, but I think 275’s fit, but most 285’s do not. Fear not, I’m sure members will be along shortly to correct me if I am wrong.

So back in March I got a wheel / tire pack 275/70/18 Nitto Terra Grappplers G3 and Method 8.5 inch wide wheel with a 40 offset.

They have fit perfect , flush, no rubbing at all. It has been all good, except when I got them, I went with a smaller 275 instead of 285 because I thought I may want to go up in a size.

Well now that has time has come. I have just ordered a set of 285/70/18 Toyo Open Country AT3’s. They should be here Monday.

I’m going to put one of my Nitto’s 275 on my spare as well.

I believe this 285 upgrade will have a slight more poke than my current tire package which is what I want. I went with AT3 over the G3’s based on what the poke will reveal once installed. Thoughts ? I will post pics once installed

Thinking Maybe I should’ve stayed with the Nitto Terra Grapplers G3’s in my soon to be 285 instead of going with the Toyo A/T 3’s? I have had a good results with G3’s in 275- just thought I will try a different style?? Thoughts?

 

[LCOceans]

May want to consider the Toyo AT III in 285/75/18 if considering 35" tires. They are E load but more on the lighter side at 65lbs for the size. 11.3" wide.
I do not think they will fit in spare area underneath although I have not tried to fit one. I leave the OEM size tire under there.

 

[BigSherm]

May want to consider the Toyo AT III in 285/75/18 if considering 35" tires. They are E load but more on the lighter side at 65lbs for the size. 11.3" wide.
I do not think they will fit in spare area underneath although I have not tried to fit one. I leave the OEM size tire under there.

Whatever im going with im putting my soon to be old 275/70/18 G3’s onto my spare. Im just liking the sidewall looks better on the G3 compared to the Toyo - seems a bit more rugged and square where as the Toyo more rounded…. Just dont know if im going to see a huge difference in a 275 to 285 upgrading to a more rounded sidewall type tire?

 

[ultane]

Thinking Maybe I should’ve stayed with the Nitto Terra Grapplers G3’s in my soon to be 285 instead of going with the Toyo A/T 3’s? I have had a good results with G3’s in 275- just thought I will try a different style?? Thoughts?

I am the #1 wrong person to get tire advice from.

I would have thought the Toyo A/T 3’s to be better than NITTO’s.

I will always chose stock tire size, keeping weight in mind, and only a modest (at best) tread design. My new Bridgestone Dueler AT Ascents (3PMSF) will arrive this coming week, and will be installed the following week. I chose them because they are known to be a quiet tire. Even the OEM Michelin ATX’s are howling now after 36,000 miles.

 

[BigSherm]

I am the #1 wrong person to get tire advice from.

I would have thought the Toyo A/T 3’s to be better than NITTO’s.

I will always chose stock tire size, keeping weight in mind, and only a modest (at best) tread design. My new Bridgestone Dueler AT Ascents (3PMSF) will arrive this coming week, and will be installed the following week. I chose them because they are known to be a quiet tire. Even the OEM Michelin ATX’s are howling now after 36,000 miles.

My 275’s G3’s have been great on my Method 18’s . Quiet. Factory stance. OEM quality. Just been great. When I went to get my larger size upgrade to 285, the tire store said they don’t make the G3’s in that size - so I went with the yoko OC A/T3’s… seems kind of odd….since I got my 275 G3 from the same tire store??? Weird??

 

[BigSherm]

Ok - after talking with Nitto, they are currently out of stock for the 285 Terra grapplers G3’s, therefore, I went with my original order of the Toyos. To be honest the sidewalls look almost identical. This is from a 275 to 285/70/18 most probably can’t tell. I put the 275 on the spare.

The first pic is the 275

 

[LCOceans]

Nice looking and good size. I may put this tire on mine when I need new tires. 34" basically. Nice stance. Please let us know what kind of mileage you see with these. I feel like I get reasonable mileage on my Open Country tires given they are 34.8".