KO3's!!!

[msenske]

Based on all the feedback from this thread, I increased my tire pressure on my 265/70R18 124S RWL KO3s from 38psi to 46psi. I spoke with a BFG representative as well as referenced the tire pressure calculator mentioned in this thread, and both helped me land on 45-46psi. So far the ride is great, with cornering being much improved. I haven’t driven enough to see what, if any, impact this change has made to fuel efficiency. Thank to everyone for the exchange of information and the thoughtful discussion!

 

[msenske]

Not sure if anyone has posted the BF Goodrich Load & Inflation tables yet as the thread has quite a few posts, but here they are in the event that someone needs them. The Light Truck Load & Inflation Tables begin on page 24 of 30 in the document and the specific reference to the KO3 in the OEM size of LT265/70R18 124S is on page 26 of 30.

 

[Buckfever]

So cold they're at 46 PSI this morning and hot the rear left needed a little air. Surprisingly it doesn't feel as bad driving this morning even over the tracks. I think maybe coming from the SL tire to the LT tire that was just the initial impression. And as was mentioned by @msenke the steering is tighter. We will see what happens with the MPG after some time. Thing is my comfort has definitely increased with this vehicle so I am driving with a good bit more enthusiasm and that can't help any,

 

[Buckfever]

“Thanks for contacting the BFGoodrich Consumer Care Team.

We would recommend using 45 PSI for these tires”

Response from BFG.

 

[Buckfever]

And for some reason now this calculator also gives the 45 psi recommended by BFG.

Tire Pressure Calculator

Easy to use tire pressure calculator. Use our tire pressure calculator to calculate the new tire pressure needed when changing tire sizes.

tiresize.com

 

[Buckfever]

We are now down to 20.3 mpg. I can't seem to get myself to stop running at 84mph on the highway.

 

[Buckfever]

Interesting tidbit, it's colder here so the cold PSI in the morning is at 44PSI.
So it got me wondering, turns out the industry standard is that the cold PSI is at an ambient temperature of 68F or 20C.

I didn't know.

 

[Buckfever]

Down to 20.2 MPG. I am driving at higher speeds as I am much more comfortable with the vehicle. so that is a factor, but I would say that you're going to lose some with these tires as they are a good bit heavier. I'll keep reporting and see what the total drop is. Drove off the lot at 20.6 MPG when I had the tires changed out so a .4 drop so far.

I really like the character of the vehicle with these tires and depending on the snow performance I may be done.

The only thing I would say is for sure go for a snowflake rated off road tire, BUT if MPG is a priority, maybe consider a non LT tire for the savings in weight.

Someone here put LT285 65 R18 on the stock rims. Honestly that probably would have been my preference however the spec sheet on the KO3's state the minimum rim width is 8" and the stock rims are 7.5" so I didn't want to push it. Those tires though are a good bit heavier so you'll lose even more. That said the stock size looks pretty damned good.

 

[OzLC]

Buckfever... have you tried chalking to get to the proper air pressure for your tire and vehicle? I drove a 2023 Bronco Badlands for 25K miles on 35" KO2's. The recommended pressure of over 40psi gave a really harsh ride. I chalked them and took the pressure down to 33 psi with no issues and a much improved ride quality.

What Is The Chalk Test For Tire Pressure? - Four Wheel Trends

If you want to prolong the life of your tires, one of the most important things to do is to keep track of is your tire pressure. There are a lot of different

fourwheeltrends.com

 

[Buckfever]

So I saw 20.1 MPG for one day but it's back to 20.2 MPG for some days now. So I'm thinking it's leveled off. I would say that the stock size KO3's will cost about .4-.5 MPG.

 

[Buckfever]

I drove in the city today. There is just no damned way that 45 PSI can be the correct pressure. It was so freaken harsh. There is just no way that kind of pounding can be good for the chassis. I reached out to BFG for guidance about lowering the pressure and I'll report back. But for now I'm going to bring it down to 42.

 

[Captain Trips]

I drove in the city today. There is just no damned way that 45 PSI can be the correct pressure. It was so freaken harsh. There is just no way that kind of pounding can be good for the chassis. I reached out to BFG for guidance about lowering the pressure and I'll report back. But for now I'm going to bring it down to 42.

I’m running mine at 33 psi just like the door sticker says. One of these days I’m gonna do the chalk test, probably after I get my ARB mounted and can do the four tire inflate/deflate.

 

[Buckfever]

So running them at 42 PSI you can forget about the MPG, because I immediately change my driving characteristics because I just do not feel safe with the pressure at 45. The 42 PSI it's well planted and highly responsive and I feel in control. It still feels a little harsh over rougher patches. I would prefer it at 39PSI, but I can live with this until BFG gets back to me.

I am not going back to 45PSI I don't care.

 

[msenske]

So running them at 42 PSI you can forget about the MPG, because I immediately change my driving characteristics because I just do not feel safe with the pressure at 45. The 42 PSI it's well planted and highly responsive and I feel in control. It still feels a little harsh over rougher patches. I would prefer it at 39PSI, but I can live with this until BFG gets back to me.

I am not going back to 45PSI I don't care.

As mentioned in a previous post in this thread, both a representative from BFG (utilizing their own load and inflation tables) as well as an independent third party tire pressure calculator indicated that the 265/70R18 124S KO3s should be inflated to 45psi - 46psi. Prior to that I was running them at 38psi. The BFG representative indicated that running them at 38psi would probably be ok in and around town at lower speeds, but that the sidewalls would degrade significantly if run at that level of inflation at highway speeds.

Like you, I preferred the lower inflation level and have definitely noticed that it is a harsher ride across uneven and broken pavement, which is all too common in and around the area where I live and work. That being said, they handle very well on smooth and/or well maintained roads at that inflation level, so there are definitely pros and cons.

I’m very interested to hear what feedback you receive from BFG regarding this matter.

 

[Buckfever]

As mentioned in a previous post in this thread, both a representative from BFG (utilizing their own load and inflation tables) as well as an independent third party tire pressure calculator indicated that the 265/70R18 124S KO3s should be inflated to 45psi - 46psi. Prior to that I was running them at 38psi. The BFG representative indicated that running them at 38psi would probably be ok in and around town at lower speeds, but that the sidewalls would degrade significantly if run at that level of inflation at highway speeds.

Like you, I preferred the lower inflation level and have definitely noticed that it is a harsher ride across uneven and broken pavement, which is all too common in and around the area where I live and work. That being said, they handle very well on smooth and/or well maintained roads at that inflation level, so there are definitely pros and cons.

I’m very interested to hear what feedback you receive from BFG regarding this matter.

Yeah I had read it and appreciate it because it corroborated the response from BFG. And I'm not questioning that is the correct calculation. What I am asking them is what is the leeway because I want to run them lighter. And yeah I'll definitely report back.

And there are so many guys that have been running the KO2's at 38-39 without incident and which has similar load rating.