35J Tire Pressure (had a blow out)

[Belgique]

Please don't weight police me....I know I'm a bad guy and I promise to rectify it ASAP.

Been running 92# as is on the Winnie placard....I KNOW that this should be adjusted after a proper weighing. I can't find a scale right now, esp one that will do 4 corner etc. Yesterday I had a right front blowout (25K on the tires and 3 years). Talking to a trusted tire guy today and he said I probably had too low of pressure! I thought I was on the high end. There was no warning and I have a TST pressure system that was showing all ok, minutes before. Thus, I'm curious as to what other 35's run for pressure. I'm heavy.

Another thought: about 1 hour and 50 miles earlier I had run across those little half ball shaped lane markers at slow speed (5mph)....I thought I had cleared them but they really shook the rig. I'm wondering of this could have weakened the tire? Everyone says no.

BTW...I was amazed that the front blowout did not cause any steering issues. Was in the right lane on 95 at 60mph. I just eased over on the shoulder. The pow scared the devil out of me...son-in-law- 4 car lengths behind me heard it.

Thanks in advance! Steve

[FDchief]

Glad to hear all is good. As far as pressures, which tire do you have, 22" or 19.5". Makes a difference.

[JohnRR]

Do you have any pictures of the tire damaged areas you could post?

You would have more chance of doing damage to the tire plies running over those markers if you were substantially overinflated rather than under.

[Belgique]

19.5. I'll see if I can get a pix. Essentially it blew on the inside and left about 12" of separation from the sidewall...some of that may be from the slow down and getting on the shoulder. It is at the tire guy's. Going to get a used one as the spare. I think 92 is high too...that is why I was wonder what similar coaches (that have been diligent about weighing), run.

[jimmccreary]

Hi Steve,
thanks for sharing your experience. Had my rig weighed but I may be heavier because I have diesel. My tires are Michelin XRV 255/80R22.5 LRG. I weigh 9000 on front axle and 16000 on rear axle with less than 400lb differential. After a chat with Michelin they confirmed the load rating table and I got 85# for rear and 90# for front.
From these I concluded that 92# cold would be a safe minimum pressure.
However, the Michelin truck tire service center said that he would always recommend 80% of max pressure as the minimum pressure (this would be 100# for me). Dont know who is right.
Can you answer a few questions:

What type, model of tire blew out?
Was your 92# a cold pressure?
How hot was it when your tire blew.
Are you towing? Tongue weight?
A pic, as asked for above, would be great.
Were your gas & water tanks full?

jim & debbie, 04 Journey 34H

[Belgique]

What type, model of tire blew out? Factory OEM Goodyear 245/70R19.5. Load Range F. Rig is a F53/V10. I'm sure I have always been at/over CCC thus the ostrich approach to weighing because I don't know what I'd do about it anyway...DW doesn't weigh much and I'm trying to lose. There are the 2 cats that could buy me some pounds Looking at the Goodyear tables I'm not far off on pressure....assuming my weight is reasonable. Gotta look for some scales.

Was your 92# a cold pressure? (92# was cold; the TPMS was showing about 100# and 70deg, as I recall).

How hot was it when your tire blew. Air temp was 60 deg; tire temp about 70.

Are you towing? Tongue weight? Yep; no clue but heavy since it is a Grand Cherokee. In my defense, that Jeep has been towed for 25,000 miles everywhere, including LONG trips in Mexico. Curious about this: it would not seem that the TOAD would add downward force on the tires...just lateral...and on the scales I don't see how the TOAD would effect real axle weight?

A pic, as asked for above, would be great. Rgr

Were your gas & water tanks full? Gas full-70 gal; water and holding essentially empty...always run that way when I can.

Many thanks!

[Fakrwee]

Hi, another thing to consider is if you are out of alignment. I've seen tires worn uneven on the inside that a fast visual won't catch.

[smlranger]

Four corner weights are not easy to find. Suggest you check with the NC DOT and see if they can weigh you. I called VA DOT and they have roaming portable scales trucks that the troopers call when they have stopped a vehicle suspected of being overweight. They offered to meet me at a local Walmart lot one morning and do a courtesy 4 corner weigh.

[jimmccreary]

Steve,
thanks for info.
I agree that with no tongue weight a toad should not have been a factor.

Maybe you just had a defective tire. It would interesting to hear the opinion of your tire repair guy if he inspects your tire.

best of luck

jim & debbie, 04 Journey 34H

[Belgique]

Just to close this out: no picture...the tire was gone. Lucked out and they had a great looking exact match Goodyear that someone had swapped out, probably for age...it's a late '99. No obvious dry rot or tread wear. They mounted it and rolled it out the door for $55! I know...it's too old to run with but it'll be a perfect spare. Hope I won't have need for one. Thanks all. Steve (who's going to find scales)

[akadeadeye]

Quote:

Originally Posted by Belgique Just to close this out: no picture...the tire was gone. Lucked out and they had a great looking exact match Goodyear that someone had swapped out, probably for age...it's a late '99. No obvious dry rot or tread wear. They mounted it and rolled it out the door for $55! I know...it's too old to run with but it'll be a perfect spare. Hope I won't have need for one. Thanks all. Steve (who's going to find scales)

No offense intended, but why in the world would you risk another blow out by driving off the tire dealer's lot with a 12 year old tire.......even if they had given it to you no charge. Tires on RV's need replacing due to age far more than due to wear. The normal age for replacement is 5 to 7 years.

You would be much safer throwing this "spare" away and buying two new front tires.

Be safe.

Don

[Belgique]

AKADEADEYE: In about 12 years of MHing, I have never used a spare. I tried to indicate that I know all about tire age but guess I failed. I'd just as soon not spend $400 for a spare when I am going to need to replace all 10 tires in about 3 years because of age (they are all 3 years old now). Hopefully, the $50 spare will never touch the pavement. If it does, it will be just long enough to get off the highway and at reasonable speed to get to a CG where I'll buy a new tire(s).

[John Mo]

I try to keep the Goodyears on my F53 35J at or above 90 PSI. We tend to be at the high end weight-wise and I don't think I'd notice any tiny improvement in ride quality from a lower pressure even if it was an option to better match my exact weight. I am also inclined to keep the pressure higher if there's any chance it helps with fuel economy, but as with the ride quality, any improvement there is probably negligible. In all cases, I'm inclined to believe that it's better to err on the high side when it comes to tire pressure.

You might be pleasantly surprised if you go weigh your coach. The 35J actually has very good CCC. I've weighed mine a couple of times. The most significant weighing was at the start of our 2008 Montana trip. We had 8 people on board and I was really concerned about being overweight. IIRC, I had the fuel tank full, the water tank at about half, and the waste tanks at or near empty (my preferred configuration for covering a lot of distance with campground hook-ups every night). I used a CAT scale and found that I was close to, but under both the front and rear axle limits. That Montana trip was a special occasion and I don't expect we'll ever be packed that heavily and carrying that many people for that distance again. Since then, I've not worried a lot about weight.

A four-corner weighing would probably be enlightening. I think the 35J is heavy on the right side, especially in the back.

I'm happy to hear that yours handled well when the tire blew. It's a scenario that I've played out in my head many times, but I hope I never have to experience.

[Belgique]

Thanks much for the great info! If you have a second, describe how one weighs on a CAT scale at a truck stop. Do you go in first and tell them or what? Presume it would be 2 passes get get the front and rear separately.
I'm thinking the right side has to be heavy what with the galley, bunks, closet, and the drawer under the bunk that I have loaded. I switched that heavy CRT TV for LCD so gained a little there. Sure Winnie engineered all that though.
I was REALLY surprised when the TPMS showed it was the right front that blew. I was sure it was rear. The steering wheel did not move and there was no action at all. Amazing. I was able to do a moderate slow down onto the shoulder with no issues. And, before someone asks, the steering is just like it came from the factory...no "Steer-Safe" etc. From what I've read, they are not always this was gentle so I was lucky.