Yet another BFG Tire fail.

[vlamgat]

That's right - 1 psi down for every 10 deg over ISA or 68F and similarly 1 psi up for every 10 under 68 although it is not linear. So in Arctic conditions its lesser amounts of pressure for a wider band of temperatures. So when its blowing 20 mph in Green Bay at an ambient of -20 you should not be increasing your pressures by 9 psi !

Race cars are typicall inflated to level that when the tire is at operating temp of +160F (usually closer to 200F) they will be at the rated pressure for that load rating. In my Gti on Hoosier A6/S6 I start at 30 psi and the tire gets to 42. In the Summer they blew past that and I was bleeding off 4 to 6 psi after 5 laps. That usually meant that I went out under inflated as I could not afford to stop during a race to bleed down. I suggest that our van tires need nothing like this degree of attention and whether you start at full load with 80 psi at 68 deg or 78/82 - your tire will not fail for THAT reason. In any event many gauges are at least 1 and oten as musch as 5 psi inaccurate based on my esperience.

[witoke]

I just had a BFG AT blow out on me as well. Luckily it happened when I was on a dirt road, driving perhaps 20 or 25, not doing 70 on the highway as I had been 20 minutes before. I actually heard the sudden hissing noise through my open window. Inspection revealed a quarter size area in the tread where the casing had just cracked open in a uneven shape. The tires had 50% or so wear and I am always careful with inflation pressures. No rock hits or other damage, just the weird cracking of the tire itself. Same as everyone else has described. I just put two new ones on the back. Bummer, I don't think they can be trusted.

I will be searching the forum for alternatives.

[daveb]

Not good. At least nobody was hurt except your pocket book. As heavy as my van is I switched to Toyo's.

[ANZAC]

Originally Posted by witoke

I just had a BFG AT blow out on me as well. Luckily it happened when I was on a dirt road, driving perhaps 20 or 25, not doing 70 on the highway as I had been 20 minutes before. I actually heard the sudden hissing noise through my open window. Inspection revealed a quarter size area in the tread where the casing had just cracked open in a uneven shape. The tires had 50% or so wear and I am always careful with inflation pressures. No rock hits or other damage, just the weird cracking of the tire itself. Same as everyone else has described. I just put two new ones on the back. Bummer, I don't think they can be trusted.

I will be searching the forum for alternatives.

front or rear?

D rated or E rated?

weight on axle where tire failed?

[BIGVANS]

Originally Posted by witoke

I just had a BFG AT blow out on me as well. Luckily it happened when I was on a dirt road, driving perhaps 20 or 25, not doing 70 on the highway as I had been 20 minutes before. I actually heard the sudden hissing noise through my open window. Inspection revealed a quarter size area in the tread where the casing had just cracked open in a uneven shape. The tires had 50% or so wear and I am always careful with inflation pressures. No rock hits or other damage, just the weird cracking of the tire itself. Same as everyone else has described. I just put two new ones on the back. Bummer, I don't think they can be trusted.

I will be searching the forum for alternatives.

Looking back on 30 years of 4x4 experience this particular case sounds like a rock punch. Besides ANZAC's requested info. Did you air down for the off road, etc.

[witoke]

My van is not an SMB (doesn't even have an SMB sticker) but a pimped out and now stripped E150 conversion van with a Quigley 4x4 conversion and a PH top. Weighs 6000 lbs unloaded and on this weekend trip it was pretty lightly packed, an extra 80 lbs of water and no more than that in food and gear. It was a front axle, drivers side. From past weigh-ins with similar loads I'd guess no more than 1750 max on the front wheel. Tyres are 109 load rated (2300 lbs) so should be more than adequate for the load.

The road is a good, county maintained one, it had been freshly graded, (as in the day before) with almost no traffic since. There were some smaller fist sized kicked up rocks on the surface but equally, the top couple of inches were loose and soft. Since the road was so good I had not aired down at all and was running at my normal 45 psi, maybe at 20 or 25 mph but probably not even that fast. I was cruising slowly up a some switchbacks, looking at some cliffs off on one side. Maybe a rock...but I certainly didn't feel anything.

I will call BFG and ask about the likely cause without any expectation of actually getting an answer. I will also pull the tire and look at the inside of the casing.

[ANZAC]

At 45 PSI, you would take -150lb off your load carrying capacity at max pressure which is probably 50psi for a C rated BFG.

You might want to consider D rated for off road and get more sidewall thickness, regardless of the brand you choose.

[Viejo]

Typo alert

You might want to consider D rated for off road and get more sidewall thickness, regardless of the brand you choose.

I'm sure ANZAC meant to say..

You might want to consider E rated for off road and get more sidewall thickness, regardless of the brand you choose.

[ANZAC]

Originally Posted by Viejo

Typo alert

I'm sure ANZAC meant to say..

You might want to consider E rated for off road and get more sidewall thickness, regardless of the brand you choose.

No I meant D (or, "at least D"). He is using C and has lower loads than most SMBs.

[witoke]

"You might want to consider D rated for off road and get more sidewall thickness, regardless of the brand you choose."


That is good advice, thank you. Although this model of tire was on the van when I got it and I have subsequently replaced them at Discount Tire, when I looked them up on the BFG site yesterday they list them as not suitable for E-series vans. Doesn't say why since the load rating is fine for my van's weight. I have 15 inch wheels BTW and the BFG's are something like 31x10.5x15.