Interesting - KO2 Tire Pressure per BFG site

[IslandJim]

Where did you guys get your KO2s from anyways, Costco won't let me install them on my 4Runner because of the load index rating. Had KO2s on my 2015 Tacoma and they were awesome! Thank you

 

[Lexington]

I actually had a tire tech argue with me about tire pressure until his boss came over and asked what pressure I wanted in the tires and told his guy to do that. I did at one point mention that I shouldn't know more about tires than he does.

I will say, I am impressed by this site so far, I'm used to people saying they run max PSI because that's what it says on the sidewall...or they run what's on the door sticker but very few in between.

Well my thought is that tire manufacturers are the experts at what they do. So in this case I’ll go by their recommendation. I assume when auto companies decide what is the best tire pressure for the car that they consult with tire manufacturers first and then they may tweak it for what they think is the optimal ride.

Yes I really enjoy this forum. I’m always learning something new. The other thing I like is when there is a difference of opinion the debates are civil and respectful.

 

[Lexington]

Where did you guys get your KO2s from anyways, Costco won't let me install them on my 4Runner because of the load index rating. Had KO2s on my 2015 Tacoma and they were awesome! Thank you

The tires are pretty common and you should be able to get them just about anywhere. I got mines from Bruce Tires but I think America’s Tires had the cheapest price. I think Costco is a rare exception where they will sell you the tire but won’t mount them for you. Maybe they worry too much about liability.

 

[Ripper238]

Curiosity question. If you run LT tires at 32 PSI listed on the door, can that cause any safety issues or does it just only means you will have less fuel efficiency and uneven wear?

Thanks again.

Yes, technically. The tire would be under required PSI and may ride soft and potentially be unstable, overheat and blow.

That said it depends on the over all weight and your use. So many times its just fine at 32 PSI.

 

[Jivewalker]

Thanks!

Until I read this post I was never aware that LT tires should run at higher PSI. I always went by what was on my door +5 PSI to improve gas mileage. Even my tire shop said they just go by the PSI listed on the door. I did call BFG and they told me they recommended 44 PSI for LT tires on the 5th Gen 4Runner. I did read that many people here prefer to run them at 40 PSI.

Curiosity question. If you run LT tires at 32 PSI listed on the door, can that cause any safety issues or does it just only means you will have less fuel efficiency and uneven wear?

Thanks again.

Yes to all of your questions for normal driving. Airing down off road at slower speeds is of course an exception. I ran my KO2's at 32 for a while and they began to cup, that is when I looked into it and discovered I needed to adjust for the LT tire. After that, they went 90k no kidding. Now on my second set on the runner and may put some on my Land Cruiser unless I decide to go with Defenders.

Additionally, if you have heavy accessories like bumpers, skids, RTT, etc. then you may want to research and recalculate your weight and re-run the math on the inflation tables listed above for maximum performance. Hope this helps.

 

[mainerunr]

Well my thought is that tire manufacturers are the experts at what they do. So in this case I’ll go by their recommendation. I assume when auto companies decide what is the best tire pressure for the car that they consult with tire manufacturers first and then they may tweak it for what they think is the optimal ride.

Yes I really enjoy this forum. I’m always learning something new. The other thing I like is when there is a difference of opinion the debates are civil and respectful.

I usually go with what the manufacturer says too. The installer is a different story though.

 

[scfw0x0f]

Ok, I double checked the math. My original P dunlops were rated at 2425lbs at 32psi, then derated to 2204lbs being on the light truck (4runner). Cross that over to the TAKO2's LT chart, and 44psi makes sense, 45psi would be 2255lbs.

At 40psi now, going to give 44 a try for the hell of it. I realize everyone has done this already and this horse has been beat to death over the past 10 years, but I guess I'll see for myself and add to the validations!

Thanks for posting this. Falken Wildpeak A/T3Ws, here's the excerpt from their chart attached. Sounds like 44PSI (43.58 to be pedantic ) would match the Dunlops. Local dealer set them at 38, which has been ok but maybe it's time to pump them up a bit.

 

[Jivewalker]

Thanks for posting this. Falken Wildpeak A/T3Ws, here's the excerpt from their chart attached. Sounds like 44PSI (43.58 to be pedantic ) would match the Dunlops. Local dealer set them at 38, which has been ok but maybe it's time to pump them up a bit.

Cool. For the load rating I believe you round up. The ride is a bit harsher for sure due to the higher pressure but the wear and stability has been better. Really wish they made a P rated KO2 to run in the 32 range. I guess that's the compromise you make going to LT.

 

[hoppyjr]

I called BFG support number yesterday and asked about this. I’m running 275/70-17 K02’s on my 2022 TRD ORP.

BFG guy used their data on vehicle (year/model/trim) and their chart on load index for my specific tire. He said I should be running 45 psi cold, but to pump it up more if towing.

I asked about stock 265 size on same vehicle and his calculations show 50 psi for that.

I was surprised, but his explanation did make sense, as it showed load capacity vs pressure in his chart.

 

[Grug556]

I called BFG support number yesterday and asked about this. I’m running 275/70-17 K02’s on my 2022 TRD ORP.

BFG guy used their data on vehicle (year/model/trim) and their chart on load index for my specific tire. He said I should be running 45 psi cold, but to pump it up more if towing.

I asked about stock 265 size on same vehicle and his calculations show 50 psi for that.

I was surprised, but his explanation did make sense, as it showed load capacity vs pressure in his chart.

Thats gotta be the E rated right? The C in 265 seems good around 40, 45 is to high and it rides poorly.

 

[Lexington]

Thanks for posting this. Falken Wildpeak A/T3Ws, here's the excerpt from their chart attached. Sounds like 44PSI (43.58 to be pedantic ) would match the Dunlops. Local dealer set them at 38, which has been ok but maybe it's time to pump them up a bit.

SCFW. How are you calculating the precise tire pressure? It seems you’re using some formula and not just a chart. I found this formula from a you tube channel.

So this says
Actual axle tire weight load / Max tire load x Max tire PSI = Recommended PSI

So if the 4Runner GVW is 4,400 lbs (TRD Pro) that give a per axle weight of 2,200 lb
(If anyone know the actual front and rear axle load please let me know)

KO2 265/70R17 C Load
KO2 max weight load is 2,470 lbs

KO2 max PSI is 50

2200 / 2470 x 50 = 44.53 PSI

Is this correct?

Thanks
How to find your optimum trailer tyre pressure (and why it may not be the same as your car) - YouTube

 

[hoppyjr]

Thats gotta be the E rated right? The C in 265 seems good around 40, 45 is to high and it rides poorly.

I actually didn’t ask on load range for the 265.

My 275’s are “E”

I’m not thrilled with the ride of my 275’s @ 45 psi either. They came on my 4Runner as I purchased used with 637 miles. If I were doing this I’d stick with 265’s as they are 11 lbs per tire lighter.

 

[mbm112]

Fwiw, the recommended cold pressure for a Rubicon on stock KO2 285 C loads is 37psi.


Sent from my iPhone using Tapatalk

 

[N2TRKYS]

How are you determining the proper PSI? Does BFG have a chart or is there some online calculator for this? I just always assumed you went by the PSI on the side of the door? Thanks

You can also chalk test your tires for proper psi.

 

[hoppyjr]

You can also chalk test your tires for proper psi.

Very true, I was doing that back in the early 80s and it’s a great way to determine if you’re going to get uneven wear. Unfortunately, it doesn’t have anything to do with load index.

 

[N2TRKYS]

Very true, I was doing that back in the early 80s and it’s a great way to determine if you’re going to get uneven wear. Unfortunately, it doesn’t have anything to do with load index.

Did you not find that the test put you close to if not at the top of the psi rating?

 

[scfw0x0f]

LT tire pressures

The info I posted was for LT265/70R17 E-rated. I don't see a listing for C-rated.

I'm not able to upload the PDF, but it's here:
https://www.toyotires.com/media/pxcjubjs/application_of_load_inflation_tables_20200723.pdf

Also, there's a good discussion of load ratings here:
Discount Tire | Tires and Wheels for Sale | Online & In-Person

I don't see a distinction between C-rated and E-rated for inflation recommendations; it seems that it's just a matter of the maximum inflated pressure, which then dictates the maximum load.

I note that when I plug a 2021 ORP into the Discount Tire site, it offers the C1- and E1-rated KO2s but not a C2. There may not be a KO2 C2 in that size, of course.

This all sounds to me like C-rated and E-rated should be inflated to the same pressure for the same load weight, and that we shouldn't be using C2-rated tires on 4Runners as there's no way to adequately inflate them.

Harshness: try riding on run-flats sometime. Stiff *and* noisy. E-rated Falken A/T3Ws at 40psi are almost silent by comparison.

 

[Old Tanker]

...I don't see a distinction between C-rated and E-rated for inflation recommendations; it seems that it's just a matter of the maximum inflated pressure, which then dictates the maximum load...

That's how I understand it.

 

[stevelikesrhino]

This all sounds to me like C-rated and E-rated should be inflated to the same pressure for the same load weight, and that we shouldn't be using C2-rated tires on 4Runners as there's no way to adequately inflate them.

DOT standard load inflation table is shared across all LT tires at the same size, no matter range C or D or E or F. Load inflation tables for D E F just extend cold inflation pressure above 50psi.

 

[scfw0x0f]

DOT standard load inflation table is shared across all LT tires at the same size, no matter range C or D or E or F. Load inflation tables for D E F just extend cold inflation pressure above 50psi.

Thanks for detailing that!