PSI for BFG KO2? Normal and Towing

I've been trying to find data on where to set the PSI on my KO2s both in standard mode and when towing. My greatest concern is when towing with ~700 lbs of tongue weight added to the rear. Has anyone found a table or chart that indicates what they were engineered for?

(I've had issues when towing - I'm towing a 5,500 lbs trailer w/ ~ 700 lbs of tongue weight - and I'm going through the whole system to see where these issues may stem from. Tire pressure is one of those areas I want to check.)

Can't recall which size / load KO2s you have, Dan? BFG Customer Care says a tire like their LT265/65R18 KO2 - or any other E-load tire with an 80 PSI max load - would require 48 PSI front, 55 rear to match the equivalent Land Rover OE specs of 36F and 42R for the stock tires (the LR4 uses XL rated tires.) If you contact BFG and tell them what the weight of your car on each axle, I bet they will be able to recommend the correct pressure for you.

Thanks, Umberto! I do have the KO2s with the E rating. I just heard back from BFG and they confirmed that for the 2014 LR4 I should use 45 front and 55 rear. They would not recommend a specific PSI for towing of course but they did state the following:

"...your LT265/60R18/E (tire size) can hold 2,475lbs at 60 psi, 2,755lbs at 70 psi, and 3,000lbs at 80 psi (max)."

So I would need to estimate or measure the axle weights when towing. But this at least gives me a baseline.

umbertob said:

Can't recall which size / load KO2s you have, Dan? BFG Customer Care says a tire like their LT265/65R18 KO2 - or any other E-load tire with an 80 PSI max load - would require 48 PSI front, 55 rear to match the equivalent Land Rover OE specs of 36F and 42R for the stock tires (the LR4 uses XL rated tires.) If you contact BFG and tell them what the weight of your car on each axle, I bet they will be able to recommend the correct pressure for you.

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What tire pressure do you run on your LR4 Umberto? I would think that
48 PSI Front and 55 PSI Rear would give a very harsh ride.
I run 42 F and 48 R for daily driving. When I have 6 or 7 people in LR4 I increase the pressure to 45 F 51 R. I have put over 27,000 miles on my 1st gen. TA KO ( 265/65R18) (highway and off road). Tread wear is even . I do 5 tire rotation pattern every 5,000 miles. My tires are missing chunks of tread and have nicks in sidewalls but those are related to off road roading.
My set up is similar to yours plus transfer case skid plate ( so lots of extra weight in every day driving ).
Should I switch to 48-55 PSI for daily commute.

About 45-46F and 52-53R on my LT285/60R18 Nitto Terra G2s. I am almost always riding solo, so unless I am wheeling and need to air down I keep them there all the time. Ride is great - firm and responsive but not harsh at all. Even wear thus far, and these Nittos will last me at least 50K miles by the looks of it. I like the handling better than when I used to keep them both under 50 PSI, but the somewhat less aggressive tread of the Terras may make the difference compared to the KOs. Road noise seems marginally lower, too.

Thanks. I will give it a try and increase tire pressure, to one you run, to see how I like it. I may try 48-55 PSI on my trip from Phoenix to San Francisco..

I have been running 42/48 in my K02's. Guess I'll try bumping that up a bit!

I've been at around 42/48. I'm happy there!

TL;DR version: I'm running 50F/R on my E-rated 80PSI Cooper tires and then use that as my "max" and calculate the rest of my airing down calcs from there.

Longer version:

I went with the new Cooper Discoverer S/T Maxx AT/MT hybrid E-rated truck tires with the 3 ply sidewalls. I figured best to have the beefiest tires possible knowing that the entire trip was pretty much off-road. They are capable of taking up to 80psi. There seems to be little useful information about how to set pressures on them when you're running them on such a relatively light truck.

I get the concept that if your road pressure is X, that you'd be at roughly X-25% for washboard, X-33% for slickrock, and maybe X-50% for sand.

With stock tires that are designed for 43psi, that would mean: 43 / 35 / 29 / 22
But these tires can hold up to 80psi: Using the same math would be 80 / 60 / 55 / 40 and I just found those all way too hard to drive on.

After testing 70 and then 60, I ultimately settled on 50 as my "max"/street pressure and adjusting down from there to make it: 50 / 38 / 33 / 25.

So far this has given me a great combination of highway driveability that's just right as well as the right amount of flex in the sidewall when I'm all the way down at 25psi in sand.

I have also seen reference to running a "chalk test" on the tire (I think Scott Brady mentioned it somewhere) to assess the exact right street pressure for your specific tire / weight that you're running but I haven't done it yet.

I had not thought to just call Cooper and tell them the vehicle weight and see if they had a look up table. That would have saved me a lot of guesswork and trial and error. Thanks (again) [mention]umbertob [/mention].


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Does anyone have a winter recommendation for K02 inflation? Same as street? Currently at either 48/55 or 45/52. Thanks!