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BF Goodrich tire pressure?

S

superscythe

NAXJA Forum User
Location
Michigan
I recently bought a set of BF Goodrich A/T's, 235/75/15LT. The max tire pressure is 50 lbs. What tire pressure should I run these at? I mostly drive on the highway with occasional light off-roading. I am currently running 40 lbs. of pressure. This is a stock '89 Cherokee Laredo with Off Road and Trailer Package. I want these tires to last a while, they aren't cheap. Any thoughts?
Thanks.
 
Easy way- Draw a line across the tread with white shoe polish, let it dry. Drive around the block, look for an even wear pattern across the tread, not to much up the sidewall. When the pattern is even...the pressure is right.

Easier way - 30 PSI (maybe)


Rev
 
I'm around 30-35lbs, depends on whether it's winter or summer air :D
 
jeepguy97 said:
Don't run BFGs too low the toughguard lip around the rim opens up and lets dirt get trapped and doesnt seal as well. I ran around 40 and was fine.
Click to expand...

Agreed. As with ANY tire, better to be 5PSI to high, than 1PSI low.


Rev
 
235/75 is only one size larger than stock 225/75s. The factory calls for running 225s at 30 psi. There is no conceivable reason to run a LARGER tire at a higher pressure than what a stock tire calls for. If anything, a larger tire should be run at a lower pressure.

30 psi is all you need. Any more and you'll wear out the middle of the tread long before the shoulders begin to wear.
 
Normally I would never diagree with Eagle but this time I have to....I had BFGs and always ran all my tires at 32 psi, however on two seperate occasions on two seperate tires, I got dirt lodged between the lip (special on BFGs) and the rim and it caused a leak. Both times I had to remount the tires after cleaning the debris out. I aired them to 40 and never had a problem again. It keeps the bead tighter.
 
Trust me, here's what you do: If your Jeep is pretty close to stock weight, run around 33. Not below 30 or above 36. It doesn't really matter if you are in that range. Wear will be even. The lower in the range, the cushier the ride. The higher in this range, the sharper the steering and handling. Your choice. Also, rotate them front to rear every 10,000 miles. Keep the left tires on the left side and right on right for the entire life of them, just go front to back every 10,000. Also, get under there and check your toe. Measure the distance of the front of the tires and the rear of the tires. Should be as close to the same as possible. Be as precise as you can. Once you get the toe at 0, you are set, as Jeeps almost never come out of alignment unless you hit a building at 80 mph. With this, 50,000 miles or many more should be easy on those tires.
 
Rev Den said:
Easy way- Draw a line across the tread with white shoe polish, let it dry. Drive around the block, look for an even wear pattern across the tread, not to much up the sidewall. When the pattern is even...the pressure is right.

Easier way - 30 PSI (maybe)


Rev
Click to expand...
I'm with Rev on this one. This has been beaten to death over and over... each jeep weighs different, each driver weighs different and the chack method takes about 10 minutes one day to get it right.
 
Every once in a while when I get suspicous that the alignment is out I find a dry flat parking lot and pour water on the tires. Then let it idle in 1st for about 50ft and look at the track it left. Found out over time it is usually a result of one of the tires being 2-4 psi lighter or heavier than the others. I tend to run a bit towards 35psi cold in the summer and 32psi cold in the winter. 35 psi in the summer generally gets up to 38 after the tires get hot and the 32psi in the winter generally gets up to 35 after they get hot.
You can also check the tires for proper inflation with some chalk across the tires, put some wide chalk marks across them and drive in a straight line. Then look at the chalk line. if it is worn off in the center thats over inflation, on the edges thats under inflation. If we had a nurse or something in the family the white shoe polish would be just as good but the only colors I have are black and oxblood :D Though I might buy a bottle of that kiwi liquid stuff with the applicator, might be a tad easier then using chalk. well, gotta get back out on the road again...
 
I've used BFG A/T tires for many years and usually have them aired to about 32 psi, sometimes a little lower with the larger sizes. They have worn evenly and have lasted a very long time. I'm with Eagle on this one. 40 PSI (and above) makes for a rough ride, but whatever works for you.

Tom
 
Guys, If you go to the BFG tire selector and put in your vehicle you will find the pressure. I put in an 88 XJ and had to go through several trim options until I found one with a P215 tire size, they make a LT 215 and a LT 235 version of the BFG AT. For the "P" tires they recommend the 30 psi like the glove box sticker says; however, for the "LT" AT tire they say 40 PSI.

With the higher number of plys you need more pressure to have the tire able to carry the load. Like the side says at 50 PSI you can carry the max value.

If you have a bouncy ride at 40 PSI with BFG AT then you need to consider replacing the shocks. My 69 Camero said to change them every 25,000 miles, I saw a billboard where monroe says 50,000 miles. With lower pressures the tire is flexing to make up for the suspension.
 
well, i run 31"s @ 25-28 psi rear/front and haven't had problems with dirt in the crack, or bad wear characteristics. for a 235 i could see 30psi as a good pressure. had the same set for 4 years and 50K miles and they will last another 5K at least.

-J
 
I have 30" BF Goodrich T/A KO's on my XJ. Ran them at 35 psi front (240kPa) and 32 psi rear (220kPa). I did this after recommended pressures I saw on the Jeepforum for XJ's as well as on the GoJeep website. This made for a very harsh ride however. Previously I ran 245/75/15 Firestone Wilderness tyres at 29 psi front and 26 psi rear and had even tyre wear over 30 000km.

I have now decreased pressure to 26 psi rear and 29 psi in front on the BFG's and I'm getting even wear so far (6 000km) with a very comfortable ride. Any comments/recommendations in this regard?
 
I run my 30" x 9.5"s at 40 psi Summer, 35 psi Winter. I like the improved steering response and mileage at the higher pressure. The slightly rougher ride is barely noticeable.
 
Whoa! 40 psi, that's 275 kPa, can't imagine what a bone jarring ride that must be! 35 psi already feels too hard for me! I'll hang on a while longer and have a look at what happens to the treadwear. :peace: I don't think XJ's have enough weight to justify those kinds of pressure. Toyota Landcruisers, and Nissan Patrol's run that kind of pressure...
 
It's really not bad on good road surfaces. I air them down for dirt roads, snow, and the like. If the roads around here were rough, I'd likely run 32-35 psi. I did find my steering response and overall handling characteristics to be notably sharper at 40 psi compared to 32.
 
you can always call them. you can give them the details of your vehicle, and they will give you a recommened pressure. thats what i did for my tires when I went bigger, think it was 42 in my 247/75
 
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