I recently installed some LT285/70/17 BFG A/T tires on my JK. At the time of purchase I did not realize that the tires are a load range D and did not know much of what it meant. Well I have been doing a little research and now know what all of the different designations mean.

I didn't like that the tires road rougher than the originals. I aired them down to 30 psi and I guess they are tolerable. But I took it one step further and decided to call BFG and ask for their opinion on the correct pressure. They asked what vehicle I had, the original size tire and pressure, and what tire I had installed. They put me on hold for a little while and came back with an answer of 55 psi. I said this sounded a bit to much but they reassured me that they were correct. Well I haven't tried 55 psi and don't intend to. I don't even know if the wheels are rated for this much pressure.

I really don't like the ride now and have been looking at getting either a P metric size all terrian or a load range C tire. Do you think there is much difference in the P metric to load range C on ride and handling? It will be on road 99% of the time.

 

this is exactly the reason why i wet with rubi wheels.

But if BFG suggests 55 PSI I would do it.

You dont want a blow out from overheated side walls caused by under inflated tires

 

run about 35 and you will be ok

 

I run mine at 45psi....55 was too hard, and 35 was too spongy.
I could be doing something wrong, but 45 feels mo better.
I could never get a definative answer for correct tire pressure from ANYBODY who was supposed to know.
Congratulations for getting an answer (even if you didn't like the answer) on your correct pressure.

 

Ratings such as C & D load ratings are really base off how much loads you will have on your vehicle. specially on trucks. a JK Unlimited is pretty much the same weights compare to my 00 Jeep WJ. 30-35 psi would be consider as standard. and anything more you will be risking the chance of you driving down the street and go BOOOM!...


I have my Wj's BFG MT set at 32PSI and thats with winch, ARB bumper, Winch, rear bumper, roof-rack, and bunch of other heavy parts. total combin my Wj weights close to about 5000lbs.


anyway... stay within 30-35 psi you would be much safer, rids comfortable and more even tire wears.

 

sigh.

OK, the 285/70/17 load range D BFG AT ko is rated ata a maximum PSI of 65 psi...so, you will not explode at 55, or even 65 psi.

It ALSO rated to carry damn near 3,200 lb at 65 psi...max load, at max pressure.

Assuming you might have a gvwr of around 5,200 lb or so, each tire only has to support about 1,300 lb per corner at that load, with a 70% or so shift to the front tires in extreme braking, etc...so, ~ 2,200 of support might be a safe target load.

Its not a linear relationship between psi and load, but, for ballpark purposes, lets say you want around 69% of the max load capaciy....times 65 psi = ~ 45 psi.

This is EXACTLY what A'sJK posted he found to be perfect, for him, aftr trial an error....indicating that 45 psi, for the load range D 285/70/17 BFG AT ko, is probably about right.

Hope that helps.

 

What he said.

 

Just for fun I emailed BFG about this and here was their reply to me concerning a Sahara Unlimited:
Thank you for your email. We appreciate the opportunity to serve you.

We would recommend you stay at 35 PSI it would carry the load required by
the vehicle manufacturer.

Thanks for choosing BFGoodrich.


If your questions have not been answered to your satisfaction, please call
me at 1-877-788-8899 (toll-free) between 8:00AM and 8:00PM Eastern Time
Monday through Friday.


Sincerely,
John
BFGoodrich Tires
Consumer Relations Department

I'm thinking of going 40 PSI though to comensate for skids, bumpers and winch.

 

What he said was someone on the phone at BFG suggested that. They may have been answering the phone at pizza hut the week before. (nothing against pizza hut, My daughter loves it)

If your BFG tires are anywhere near as durable as mine were, You will never have a low pressure blow out.

I had a slow leak on almost every bfg at on my old cherokee. I really lax about checking pressures & waited for a noticeable bulge before airing up again. I would usually have at least on tire down to 10 to 12 psi. They never blew out. I ran this way for 2 years & never had a problem. 55 psi is within the pressure rating for that tire but it will feel like your tires are made of cement at that pressure. With that much pressure, you may notice a slight increase in mpg and accleration, if you're really in touch with the handling of your vehicle.

 

On my xterra... jk is coming in the end of this month i hope... i have bfg AT's and i always ran at like 32-35 psi... till one day i was at a tire shop gettign a bfg AT spare mounted on my 71 cj 5 spare rim ... and the hillbilly tire guy , nice guy, looks at my xterra tires and says "your tires are crowning!" i said"ummm" he tells me my pressure is too low for those tires and says i need to run 50 -55 psi in those.... so i aired them up and damn it felt better.... more responsive, as responsive as that elephant can get i guess,less wishywashy, but it felt firmer and handled better..... so i've run 50 ish for the last 1.5 yrs..... tire guy said tires would wear funny if i ran them at 32ish psi .... also I love BFG AT's Ive had them on my Cherokee , my CJ5 and Xterra and want them for my JK asap.... i love them.... they wear GREAT and arnt to loud.... i'd marry them if i wasnt already married. .... just my 2 cents