Tire Pressure recommendation (3 Viewers)

[Arcturns]

Nitto does not make a Ridge Grappler in size 285/70R18, so I must assume you meant the LT285/70R18 E 127/124Q Ridge Grapplers. I also assume you are putting these on a LC200 and not an LX570.

If both of my assumptions are correct...

The Recommended Cold Tire Inflation Pressure for the LT285/70R18 E 127/124Q Nitto Ridge Grapplers on your 2013 LC200 is 38psi F/R.

HTH

@gaijin A few years back you graciously provided me with tire pressure recommendation for LT285/70R18 E 127/124Q Ridge Grapplers on a 2013 LC at 38 lbs. Since then I have added a SLEE rear bumper, HiLift, ARB drawers, roof top tent (135lbs), ARB awning. From there it gets further weighted down with gear. I don't have an accurate estimate of vehicle weight, but the increase is obviously substantial. With the added weight it feels like the tire pressure is not adequate (quite "floaty") and the wear is rounding off the tire shoulders. Note: The tires have 40k miles on them so I'm also guessing the tire's strength integrity is starting to go away.

With that, I'm getting ready to replace the tires with a new set of the same Nitto Ridge Grapplers and concerned that 38 lbs is not enough. Probably a dumb question answered many times before, but should I be increasing air pressure or stick with 38lbs?

Thank you for all the help and guidance you provide us on IH8MUD.

 

[gaijin]

@gaijin A few years back you graciously provided me with tire pressure recommendation for LT285/70R18 E 127/124Q Ridge Grapplers on a 2013 LC at 38 lbs. Since then I have added a SLEE rear bumper, HiLift, ARB drawers, roof top tent (135lbs), ARB awning. From there it gets further weighted down with gear. I don't have an accurate estimate of vehicle weight, but the increase is obviously substantial. With the added weight it feels like the tire pressure is not adequate (quite "floaty") and the wear is rounding off the tire shoulders. Note: The tires have 40k miles on them so I'm also guessing the tire's strength integrity is starting to go away.

With that, I'm getting ready to replace the tires with a new set of the same Nitto Ridge Grapplers and concerned that 38 lbs is not enough. Probably a dumb question answered many times before, but should I be increasing air pressure or stick with 38lbs?

Thank you for all the help and guidance you provide us on IH8MUD.

The RCTIP of 38psi for those LT285/70R18 E 127/124Q tires is good up to the following vehicle weights:

GVWR: 7385 lbs
GAWR (Front): 3595 lbs
GAWR (Rear): 4300 lbs

If you go above any of these weights, or in your particular use case you find a HIGHER tire pressure to be more suitable, you are free to INCREASE tire pressure as you deem appropriate. You are not free, however, to go BELOW the RCTIP.

I no longer suggest tire pressures for vehicles above these listed weights.

As long as your vehicle remains within the listed weights, the RCTIP of 38psi will provide sufficient Load Limit, with balanced overall performance to safely meet design criteria. Adjusting above the RCTIP is always a personal choice based on personal use cases.

If you decide to try a higher tire pressure, you may find the following Load Limits for those LT285/70R18 E 127/124Q tires helpful:

RCTIP (38psi): 2309 lbs
40psi: 2395 lbs
45psi: 2600 lbs

HTH

 

[Arcturns]

The RCTIP of 38psi for those LT285/70R18 E 127/124Q tires is good up to the following vehicle weights:

GVWR: 7385 lbs
GAWR (Front): 3595 lbs
GAWR (Rear): 4300 lbs

If you go above any of these weights, or in your particular use case you find a HIGHER tire pressure to be more suitable, you are free to INCREASE tire pressure as you deem appropriate. You are not free, however, to go BELOW the RCTIP.

I no longer suggest tire pressures for vehicles above these listed weights.

As long as your vehicle remains within the listed weights, the RCTIP of 38psi will provide sufficient Load Limit, with balanced overall performance to safely meet design criteria. Adjusting above the RCTIP is always a personal choice based on personal use cases.

If you decide to try a higher tire pressure, you may find the following Load Limits for those LT285/70R18 E 127/124Q tires helpful:

RCTIP (38psi): 2309 lbs
40psi: 2395 lbs
45psi: 2600 lbs

HTH

Thank you @gaijin. The info I needed. Greatly appreciate your insights.

 

[LC CT]

What’s the recommend pressure of Goodyear eagle GT II

• P285/50R20 111H

Stock LX570 2013 wheels 20”

Thanks!

 

[gaijin]

What’s the recommend pressure of Goodyear eagle GT II

• P285/50R20 111H

Stock LX570 2013 wheels 20”

Thanks!

33psi F/R - just like it says on the placard on your driver side door jamb...

 

[colacola]

33psi F/R - just like it says on the placard on your driver side door jamb...

Hello @gaijin,

Appreciate the help if you could share……For my oem wheels and suspension on a 2019 LC 200, what is the recommended psi for 285/65R/18 Cooper Discoverer At3 XLT’s ?

Thank you

33psi F/R - just like it says on the placard on your driver side door jamb...

Hello @gaijin,

Appreciate the help if you could share……For my oem wheels and suspension on a 2019 LC 200, what is the recommended psi for 285/65R/18 Cooper Discoverer At3 XLT’s ?

Thank you

 

[gaijin]

Hello @gaijin,

Appreciate the help if you could share……For my oem wheels and suspension on a 2019 LC 200, what is the recommended psi for 285/65R/18 Cooper Discoverer At3 XLT’s ?

Thank you

Hello @gaijin,

Appreciate the help if you could share……For my oem wheels and suspension on a 2019 LC 200, what is the recommended psi for 285/65R/18 Cooper Discoverer At3 XLT’s ?

Thank you

Do you mean the LT-Metric LT285/65R18 125\122S Load Range E tire?

If so, the RCTIP (Recommended Cold Tire Inflation Pressure) for those tires on your LC200 is 42psi F/R.

HTH

 

[colacola]

Do you mean the LT-Metric LT285/65R18 125\122S Load Range E tire?

If so, the RCTIP (Recommended Cold Tire Inflation Pressure) for those tires on your LC200 is 42psi F/R.

HTH

Do you mean the LT-Metric LT285/65R18 125\122S Load Range E tire?

If so, the RCTIP (Recommended Cold Tire Inflation Pressure) for those tires on your LC200 is 42psi F/R.

Do you mean the LT-Metric LT285/65R18 125\122S Load Range E tire?

If so, the RCTIP (Recommended Cold Tire Inflation Pressure) for those tires on your LC200 is 42psi F/R.

Hello @gaijin,

Appreciate the help if you could share……For my oem wheels and suspension on a 2019 LC 200, what is the recommended psi for 285/65R/18 Cooper Discoverer At3 XLT’s ?

Thank you

Hello @gaijin,

Appreciate the help if you could share……For my oem wheels and suspension on a 2019 LC 200, what is the recommended psi for 285/65R/18 Cooper Discoverer At3 XLT’s ?

Thank you

Yes. Thanks

https://m.tirerack.com/tires/Spec.jsp?tireMake=Cooper&tireModel=Discoverer+AT3+XLT&partnum=865SR8DAXLT

 

[gasman4u]

@gaijin Would the RCTIP for Michelin Defender LTX M/S 285/60R18 Extra Load 120/H speed rating be 33 psi for a 2021 LE with OEM wheels? Thanks for verification!

 

[scottm]

The Recommended Cold Tire Inflation Pressure (RCTIP) for those LT275/70R18 tires on your LC200 is 41psi F/R.



By design specifications, no LT-Metric tire is recommended for use below 35psi on ANY vehicle. The best handle I can get on the rationale for this restriction is that because of the heavier construction of the LT tire, heat build-up due to tire flexing will be greater than can be normally dissipated by the tire - this would be worse at high speeds for long duration, like your "long highway runs." So... in your case, at 35psi or less, not only would the tire not have enough dynamic Load capacity to safely handle the weight of your LC200, it would increase the risk of catastrophic tire failure due to heat build-up.

My bottom line: Feel free to play around with whatever tire pressures float your boat, but keep them above the minimum recommended 41psi.

HTH

I ran them at 44psi all winter, fantastic performance in slush, snow, ice, on the highway. Best tires I've run, or maybe it is the stability control and tires, in bad winter weather. But they are noticeably rougher at that pressure, and they bounce a lot on rough spots, slightly unstable on rough highway curves. Dropped to 36psi for a 6-hour run with the wife, and they were a joy, smooth and comfortable, no bounce. Slightly more buzz from the shoulders. I suspect if I tried different shocks I might be more comfortable with the higher pressure, but would get spendy I fear. Still trying different pressures, I'm surprised how much the ride changes with small changes in pressure. I think I'm wearing my shoulders more than the center, normally all my highway driving wears the center first. I'll try a few months of 41psi before winter hits.

 

[highfructose]

I ran them at 44psi all winter, fantastic performance in slush, snow, ice, on the highway. Best tires I've run, or maybe it is the stability control and tires, in bad winter weather. But they are noticeably rougher at that pressure, and they bounce a lot on rough spots, slightly unstable on rough highway curves. Dropped to 36psi for a 6-hour run with the wife, and they were a joy, smooth and comfortable, no bounce. Slightly more buzz from the shoulders. I suspect if I tried different shocks I might be more comfortable with the higher pressure, but would get spendy I fear. Still trying different pressures, I'm surprised how much the ride changes with small changes in pressure. I think I'm wearing my shoulders more than the center, normally all my highway driving wears the center first. I'll try a few months of 41psi before winter hits.

When you start paying close attention to tire pressures, it becomes apparent that lower pressures feel more comfortable generally…my 33’s on 20” rims feel perfect at 27-31 psi, which, with passenger rated tires is an acceptable psi by load rating. With my light truck rated 33’s on 20’s, it also felt good around this psi…felt identical…but the load ratings indicated that that low of a psi is unsafe with light truck tires. It required I run 40 psi, which was jarring.

Currently I’m wondering with going with a larger tire, say a 34.4” tire on a 17 or 18” rim at 35 psi would feel as squishy as a 33” tire on a 20” rim. I don’t want to sacrifice ride comfort and go back to the jarring 40 psi ride…and even at 35 psi I find it jarring compared to 27-31.

Does anyone have an explanation as to why a 34 or 35” tire on a 17-18” whee might feel as soft as a 33” tire on a 20” wheel?

The 295 70 r18 (34.3”) tire seems like the largest tire you can run on these while still fitting in the spare tire area…but it requires 35 psi.

Does that 35 psi feel comparable to a 33” tire at 27 psi as far as the squish is concerned?

 

[gaijin]

@gaijin Would the RCTIP for Michelin Defender LTX M/S 285/60R18 Extra Load 120/H speed rating be 33 psi for a 2021 LE with OEM wheels? Thanks for verification!

Yes. Gold star for @gasman4u

 

[scottm]

When you start paying close attention to tire pressures, it becomes apparent that lower pressures feel more comfortable generally…my 33’s on 20” rims feel perfect at 27-31 psi, which, with passenger rated tires is an acceptable psi by load rating. With my light truck rated 33’s on 20’s, it also felt good around this psi…felt identical…but the load ratings indicated that that low of a psi is unsafe with light truck tires. It required I run 40 psi, which was jarring.

Currently I’m wondering with going with a larger tire, say a 34.4” tire on a 17 or 18” rim at 35 psi would feel as squishy as a 33” tire on a 20” rim. I don’t want to sacrifice ride comfort and go back to the jarring 40 psi ride…and even at 35 psi I find it jarring compared to 27-31.

Does anyone have an explanation as to why a 34 or 35” tire on a 17-18” whee might feel as soft as a 33” tire on a 20” wheel?

The 295 70 r18 (34.3”) tire seems like the largest tire you can run on these while still fitting in the spare tire area…but it requires 35 psi.

Does that 35 psi feel comparable to a 33” tire at 27 psi as far as the squish is concerned?

A larger diameter tire reduces rolling resistance on rough surfaces because it the footprint is longer, it bridges bumps and smooths the ride. I researched that on bike tires, triathlon bike had less wind resistance with small tires, mountain bike had less rolling resistance with large diameter. I'm not sure if that will make a difference for a 33" to 35"? Tire construction has a lot to do with ride. But my larger tires feel a lot like my original stock tires did at the same pressure, despite being significantly stiffer and heavier.

 

[linuxgod]

Does anyone have an explanation as to why a 34 or 35” tire on a 17-18” whee might feel as soft as a 33” tire on a 20” wheel?

With the same tires but different sizes, you’ve got more sidewalk to flex so that alone gives you more “cushion” when you run then at the same PSI.

In addition, larger tires generally require less PSI to support the same vehicle weight. I.e. a 34” tire might need 37psi but a 33” tire would need 42psi. I’d have to do the math to confirm but I suspect it’s because the total uncompressed volume of air in both tires is the same.

 

[ARKginger]

@gaijin What would be the RCTIP be for a Kenda Clever RT 35*10.5R17LT D Load 121 Speed index? Thanks

 

[gaijin]

@gaijin What would be the RCTIP be for a Kenda Clever RT 35*10.5R17LT D Load 121 Speed index? Thanks

Are you putting them on a LC200 or an LX570?

 

[ARKginger]

Are you putting them on a LC200 or an LX570?

Sorry LX570

 

[lx200inAR]

Sorry LX570

You were just a few months late in this other thread...

35x10.5x17 Kenda Klever R/T

A little more Kenda Porn for your viewing pleasure, taken this evening at a local, abandoned mine. Have any of you guys aired these down yet? What PSI are you running as a DD and what are you airing down to on the trail? The shop has them pretty stiff and I'm wondering what the consensus is...

forum.ih8mud.com

A little more Kenda Porn for your viewing pleasure, taken this evening at a local, abandoned mine.

Have any of you guys aired these down yet? What PSI are you running as a DD and what are you airing down to on the trail? The shop has them pretty stiff and I'm wondering what the consensus is on good PSI.

FYI,

The RCTIP for those 35x10.50R17LT tires on your LC200 is 37psi F/R.

If you had an LX570, the RCTIP would be 33psi F/R.

HTH

2013 URJ200L-GNTEKA w/ LT285/70R17E 121/118R BFG AT T/A KO2 DT tires @40psi F/R on 17x8x50 TRD Wheels
TLCA#: 21881
USN NAVSECGRU 1970-1974

 

[gaijin]

@gaijin What would be the RCTIP be for a Kenda Clever RT 35*10.5R17LT D Load 121 Speed index? Thanks

Are you putting them on a LC200 or an LX570?

Sorry LX570

The RCTIP for those 35x10.50R17LT tires on your LX570 is 33psi F/R.

HTH

Looks like @lx200inAR got his cut and paste in before I could finish typing...

 

[ARKginger]

You were just a few months late in this other thread...

35x10.5x17 Kenda Klever R/T

A little more Kenda Porn for your viewing pleasure, taken this evening at a local, abandoned mine. Have any of you guys aired these down yet? What PSI are you running as a DD and what are you airing down to on the trail? The shop has them pretty stiff and I'm wondering what the consensus is...

forum.ih8mud.com

FYI,

The RCTIP for those 35x10.50R17LT tires on your LC200 is 37psi F/R.

If you had an LX570, the RCTIP would be 33psi F/R.

HTH

2013 URJ200L-GNTEKA w/ LT285/70R17E 121/118R BFG AT T/A KO2 DT tires @40psi F/R on 17x8x50 TRD Wheels
TLCA#: 21881
USN NAVSECGRU 1970-1974

The RCTIP for those 35x10.50R17LT tires on your LX570 is 33psi F/R.

HTH

Thank you both