Everything about tires for LR4/ LR3 with 18" wheels

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bullmrkt

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So my tire shop is encouraging me to install TPMS sensors in my to compo's/KO2's, which they have for $60/ea, but we're not sure how the TPMS system will repond to the higher pressures (44F/50R) I need to run the KO2's at. I've read the TPMS threads and I don't see this specific concern addressed. Anyone have any experience with this? Do the higher pressures trigger faults? I'd rather just disable TPMS via IIDTool and carry a compressor, which they agreed to do if this is a problem.
 

umbertob

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The TPMS sensors only trigger a warning if a monitored tire pressure falls below the pre-programmed threshold (about 30-32 PSI in my experience, give or take a few depending on whether they are mounted front or rear.) They don't really care how much you inflate your tires, as long as you keep their preasure above that threshold you won't get any types of faults. I run my 285/60/18 Nitto Terra G2s around 48-50 PSI rear and 40-42 front regularly, and I only get tire pressure warnings when I air down before hitting a trail, something I can definitely live with. I only disabled spare tire monitoring with IIDTool, as that tire needs to be deflated big time to fit in the well under the car.
 
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bullmrkt

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The TPMS sensors only trigger a warning if a monitored tire pressure falls below the pre-programmed threshold (about 30-32 PSI in my experience, give or take a few depending on whether they are mounted front or rear.) They don't really care how much you inflate your tires, as long as you keep their preasure above that threshold you won't get any types of faults. I run my 285/60/18 Nitto Terra G2s around 48-50 PSI rear and 40-42 front regularly, and I only get tire pressure warnings when I air down before hitting a trail, something I can definitely live with. I only disabled spare tire monitoring with IIDTool, as that tire needs to be deflated big time to fit in the well under the car.

Great, thanks umbertob!
 

jwest

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The TPMS sensors only trigger a warning if a monitored tire pressure falls below the pre-programmed threshold (about 30-32 PSI in my experience, give or take a few depending on whether they are mounted front or rear.) They don't really care how much you inflate your tires, as long as you keep their preasure above that threshold you won't get any types of faults. I run my 285/60/18 Nitto Terra G2s around 48-50 PSI rear and 40-42 front regularly, and I only get tire pressure warnings when I air down before hitting a trail, something I can definitely live with. I only disabled spare tire monitoring with IIDTool, as that tire needs to be deflated big time to fit in the well under the car.

I don't think this is true .... so I'm going to test it soimetime but I have had the tpms warning come on when it drops a %. Systems are usually by %, not a preset psi . Same in my Audi and BMW. This is why there's a reset function....
 

bullmrkt

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I don't think this is true .... so I'm going to test it soimetime but I have had the tpms warning come on when it drops a %. Systems are usually by %, not a preset psi . Same in my Audi and BMW. This is why there's a reset function....

That's my understanding of other systems as well, such as BMW where you set the pressure and then reset the system to "tare" it. Can you reset the TPMS system in the LR4? I haven't been able to figure out how if so.
 

umbertob

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Yes, about 20-25% less than preset for the LR4 (the preset being 36F, 42R and 42 PSI for the spare, if monitored ) That's about 30-34 PSI depending on tire position, but it's not an exact science, as temperature and wheel speed can affect those percentages. There is no way to reset anything in the LR4's system. In some markets there is a Light Load / Heavy Load switch to change the sensitivity of the TPMS, but AFAIK that option has never been available in the US.
 
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TLB

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I think Umberto is right. Our TPMS measures real tire pressure since we have sensors and the warning is triggered below a threshold value. I run my BFGs F44/R50 PSI and higher pressure never triggered TPMS warning. My underinflated spare tire reminds about itself every time I start the truck.
On the other hand my Audi uses indirect TPMS ( ABS sensor). With Audi you can pump your tires to whatever value you want and reset the system. It will be triggered if ABS sensor detects difference in wheels rotation due to your flat or underinflated tire. What is nice about my Audi the manual provides recommended pressure for full load and partial load.
Personally I prefer ABS sensor for TPMS. ( cheaper , no cost when switching wheel or tires).
 

bullmrkt

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I installed my new Compo's and BFG KO2's in size 265/60R18 last week and love them so far. I started with them at 44psi front / 50psi rear which made for a jittery ride over broken pavement, so I lowered each value 2psi to 42/48 and the ride became much smoother. Amazing what difference such a small pressure change can make. I'm usually driving the truck by myself unloaded so I'm not worried about the lower pressure. I'll air up 2-4psi when towing or loaded up with my new VIAIR 300p (only $95 on amazon right now BTW).

Oh and I ended up having my tire shop install their TPMS sensors. $60/ea installed so I said why not. They used a special tool to read each of my existing sensors and then upload that program to the new sensors. No issues whatsoever so far.

A few photos. iPhone quality and a couple are overblown so the shadier areas were visible. It looks so much tougher now, love it.

IMG_3106.jpg


IMG_3107.jpg


IMG_3123.jpg
 

Finlayforprez

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I installed my new Compo's and BFG KO2's in size 265/60R18 last week and love them so far. I started with them at 44psi front / 50psi rear which made for a jittery ride over broken pavement, so I lowered each value 2psi to 42/48 and the ride became much smoother. Amazing what difference such a small pressure change can make. I'm usually driving the truck by myself unloaded so I'm not worried about the lower pressure. I'll air up 2-4psi when towing or loaded up with my new VIAIR 300p (only $95 on amazon right now BTW).

Oh and I ended up having my tire shop install their TPMS sensors. $60/ea installed so I said why not. They used a special tool to read each of my existing sensors and then upload that program to the new sensors. No issues whatsoever so far.

A few photos. iPhone quality and a couple are overblown so the shadier areas were visible. It looks so much tougher now, love it.
Looks great! I love my KO2s as well and have been extremely happy with the performance in many different terrains.

As for the pressure, I have been working to find the sweet spot for a while. Due to the weight on my truck (roof rack with boxes), front and rear steel bumpers, and skid plates/sliders, I have found that 46 front / 50 rear seems to work well for me, but I am still evaluating those specs. I tried 46 and 48 all around, then did front/rear different, which seemed to work better.

Thanks for sharing!
 

danrhiggins

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Have either of you tried your KO2s in snow? If our plans to go to Sedona in March work out I may get the KO2s sooner and put them on in place of my snow tires. But as we can get a late March or early April snow storm I want to be sure I'll be OK with the KO2s in snow.

Also, any thoughts on what pressure I should use for the rear if I am towing a trailer?
 

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