Author Topic: another tire question  (Read 4539 times)

rick Kirchner

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another tire question
« on: September 17, 2018, 07:48:52 PM »
I did some searching and didn't find an answer on this one.

My tires are 8.5 years old, Toyo M154s, and while the price has not risen horribly, I'm still looking at $2200 for replacement.  There was a post suggesting a place in bullhead city, and sure enough, that's the best price I've seen, and it's reasonably close to boot. 

However, 265/75-22.5 is a pretty odd size.  When driving cross-country there were all kinds of deals on tires - specifically the 295 sizes common on OTR trucks.  I've been considering those, but wanted to ask if others have done so and what their experiences are.  going to a more common size opens up more opportunities for replacement on the road.

Years ago I replaced the 245/70-16s on my 3/4 T Chevy with some huge BFG Mud-Terrains I found at a swap meet.  The transmission in that vehicle was marginal and the taller tires created considerably more heat load (like installing highway gears) resulting in overheated trans fluid puking out of the overflow whenever I went up long grades. 

So I certainly didn't want to get into that situation with the Beav - especially since I tow close to the GVCR anyway.

I know how to re-calibrate the speedo and silverleaf.  Had to do that already because they were set wrong at the factory. 

Steve Huber Co-Admin

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Re: another tire question
« Reply #1 on: September 18, 2018, 12:23:11 AM »
Rick,
Replace those 8.5 year old tires ASAP. Speaking as one who has had front and rear blowouts, the price of new tires is insignificant to the cost, damage and inconvenience of dealing with a blowout. I've got M144 Toyos on my coach now and like the performance. Only tire I'd avoid is Goodyear.
That said, I don't think a 295  will fit your coach. Get the measurements of the new tire candidates and check the clearances against your current tires, especially the clearances when the wheels are turned tightly.
Can't help on speedo recalibration. Consider using a GPS that displays speed (it's all I use).
Steve
Steve
2015-          07 Contessa Bayshore C9,  400 hp
2013-2015: 00 Marquis Tourmaline, C12, 425 hp
2005-2013: 01 Contessa Naples, 3126B, 330 hp

rick Kirchner

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Re: another tire question
« Reply #2 on: September 18, 2018, 05:51:26 AM »
i was able to test the clearance on those mud terrains right behind my house where some guys had built a little motocross track.  Got the truck completely articulated and then tried full lock.  Had to trim a tad off the front air dam.

The beav is a much tougher assessment, but I'm betting they fit from a rub perspective - 1" more radius.  The trans temp worries me a lot more, especially since it dumps it's heat into the radiator.

I have a 3" gash in one sidewall, which I've marked to watch for progression and watch it like a hawk.  it's on an outside rear.  Glad it's cooling off out here.  That guy in Bullhead is looking like the right deal.

Living where I do, its a minimum 90 mile drive to anywhere that has RV tires.

Jim Nichols

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Re: another tire question
« Reply #3 on: September 18, 2018, 01:48:27 PM »
As soon as your are able I would drive that 90 miles no faster than 50 mph. Watching a 3" gap on a tire at any speed is impossible.
Jim/Natasha Nichols
05 Monterey 36'
400 Cat C9
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Mandy Canales

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Re: another tire question
« Reply #4 on: September 18, 2018, 04:12:32 PM »
I had the same problem on my tires this summer driving to Gillette.  I was noticing on my front right tire having a small slice and periodically checking I ended up in Gillette with an eight inch slice in that same tire.  I also noticed the other front tire was starting to develop a small slice.  I purchased two new Yokohama tires just to be safe.  I surely don't want a $4,000 repair job repairing everything a blowout will cause.  I use 295/75 sized tires.  Hope this helps you make a quick decision on replacing those old tires.
 
Mandy Canales
90 Beaver Marquis 40'
Cat 3208
Charter Member
Apple Valley, CA
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Doug Allman

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Re: another tire question
« Reply #5 on: September 18, 2018, 07:35:18 PM »
Here is what I cannot seem to understand is that how the cost of tires, either a Michelin which seems to be the top price and others that are lower in cost has anything to do with personal safety of you or those with you in a coach or others along your path. Driving a multi thousand pound coach down a highway with old aged tires and especially a known gash is not only a hazard to you and your occupants but also to the other drivers on the road. Posting that you are driving with a known defect could lead to some very legal ramifications if the wrong result happened in an accident.

The cost of safety rides on your tires all the time - yours and your neighbors.
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rick Kirchner

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Re: another tire question
« Reply #6 on: September 18, 2018, 09:48:49 PM »
Thanks Mandy.  You are in Apple Valley, so you know the distance problem I'm dealing with.  I'm up in Ridgecrest, and as we joke up here, "I have to drive 90 miles to buy a nice shirt".  It appears a lot of folks in the BAC have much bigger coaches, which use the much bigger tires, which is to be expected given that the 30' Monterey's seem to be a bit on the scarce side.  Like I said, being able to use the larger ones opens up a realm of options I don't currently have, which is why I'm asking. 

I'm always kind of amazed at some of the judgements I see online.  I think suggesting that I'm somehow putting myself, my loved ones, and the general public's life at significant risk is pretty presumptuous with as little data as I've posted.  The braking and bump/roll/wind steer/side draft on a coach is far more dangerous than my tire situation.  I'm in the process obviously, of replacing them.  I'm still employed and live in a very remote location, so I don't have the ability to just drop everything and get it done - moreover, the risk is not increasing in any meaningful way while it sits in my driveway.

I'm pretty knowledgeable about tires.  I buy a lot of 'em.  I carry my own machine and balancer in my trailer.  It's because I drive one of these.  .  Have a tire problem, or more likely a lapse in concentration in one of these and you are definitely the first one at the scene of the accident....  You can actually feel when the tire pressure is off by more than a half pound or so. 

And I have a lot of tires to buy in the next few weeks.  Had two belt failures on the car hauler on the way back and a spare that didn't hold up - despite being exceedingly careful regarding weight/speed/pressure, etc.  Given that they were both on the left side I'm betting road damage - but considering this is the second set with belt problems I'm biting the bullet, buying wider wheels, going to the next larger size, load range E, and the new made in the USA GY tires that are actually speed rated.  There's six of those, and another three needed for my cargo trailer, plus the RV, and two sets for the race car.  So yeah, there's something about buying $5K of tires that will make you price sensitive.

I've read just about everything I can find online, from the manufacturers and others in the industry regarding RV tires and aging, and the consensus is that after 5 years tires be inspected annually - which I do more than annually - and that they be replaced before 10 years.  The industry consensus is also that everybody chill out about date codes - what's important is when the tire is put in service more than when it popped out of the mold.

More importantly, I know the history of the tires (which were purchased the day I picked up the coach) and the event that damaged the sidewall - which is a crack caused by stressing the rubber when it was dragged around a curb in a tight parking lot.  That damage is six years old, and while I am concerned, like I said, it hasn't progressed.  Heck, they haven't even required air in nearly three years.  I just drove it from Jacksonville, NC back here to Cali and we looked for tires all along the route, with no joy as far as finding 265/75s without a pre-order.  If I could get a better used tire I would throw it on just till I can get the others, but that brings me back to the original post:

It's an odd size; and nobody has answered original question regarding the transmission, which I doubt is a big deal, but like I said, I've had a negative experience with too much diameter in the past, and I don't want to further marginalize the cooling system.    I figure driving these mountains while towing every time I take it out is punishment enough.

So having said that, does anyone whose coach uses smaller tires have any experience moving to the larger size?

Doug Allman

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Re: another tire question
« Reply #7 on: September 19, 2018, 01:02:40 PM »
Its everyones privilege to take any info you get on the forum. However when you digest that info keep in mind that these are real coach owners that either had and have coach's and many have helped owners with coach tire problems. Owners are not manufacturers so industry standards are not most prevalent on what you can do. Info is passed on viewed from real world happenings based on what has occurred to numerous owners and some of those situations have been disastrous to their coach when tires blew, for others it was a lifetime terrifying event leaving one side of the interstate, crossing thru the median, and then going over the other side of the interstates lanes even though the coach stayed upright.
I personally sold a 1991 Beaver in 2012 and the new buyer in walk around said the tires are in excellent shape. My reply was they were "JUNK" as they were 6 years old Michelins. Yes the tread looked great but the sidewall is the critical area. We learned the costly way after blowing 4 tires that had good tread. My direction to him was to be able to drive it home (4 miles) and then get an appointment to get new tires put on before he takes it anywhere else. Our price reflected needing 6 new tires.
Had no intention of insulting anyone as the tire question is an ongoing saga for all and numerous queries on the forum in that regard. As we had in our earlier years the coach sat most of the time while we worked and sooner than we liked we had tire money needed again. Not a happy thing to want to spend on so often.

Jason Worman

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Re: another tire question
« Reply #8 on: September 19, 2018, 08:14:22 PM »
Doug

If you dont mind me asking, what did you sell your Contessa for? Overall what kind of shape was it in? We paid 18k for ours and have put about 12k into since owning it.  Thanks

Doug Allman

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Re: another tire question
« Reply #9 on: September 20, 2018, 11:51:22 AM »
We sold ours for $15,000.00 in 2012 and it was basically in excellent shape, exterior and interior with exception of tires and is why we only asked $15,000.00. RV refrigerator had been replaced year before , New Koni shocks 3 years prior, captains chairs recovered with Ultra Leather, new carpet and all cabinets in excellent shape as well as all exterior paint. We wanted more room with slides reason for sale.

John Shurtz

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Re: another tire question
« Reply #10 on: September 20, 2018, 11:43:13 PM »
OK lets talk numbers.  Your current tires are 265mm wide (10.43 in.) your tire sidewall is 75% as tall as your tires are wide (7.82 in.) your wheel is 22.5 inches tall.  after adding all your numbers up, your tire should be about 38.15 inches tall with a circumference of (119.79 in.)  There will be some variance due to tread depth.

Those 295mm (11.61 in.) wide tires you are seeing so commonly are most likely 80% as tall as the tires are wide (9.3 in,) tall. your wheels are still 22.5 inches.  After adding all the numbers up, the 295 tire should be 41.01 tall with a circumference of (129 in.) +- tread depth.

Here are the factors that should be considered:

Wheel width- are the current wheels wide enough to support the 295mm wide tires without ballooning the sidewalls?

Wheel spacing- is there enough clearance between the duals that they can not touch each other, even in an underinflation or blow out situation? We don't want one blown tire to blow out the axle mate.

Clearance- can the tires clear the body, frame and steering components lock to lock and in "Jounce" and "Rebound"?

Weight- larger tires can carry more weight. Wheels, axles, springs and frames may not.

Power/Gearing- the increased circumference of the larger tire will lower your available power by about 9.3% Does your coach have enough reserve power to overcome that loss? If not, you may overheat both your engine and transmission.

Braking- your coach will experience a 9.3% reduction in braking capability also.  Is that OK?

That is all I can think of at the moment.  You need to decide what will work for you, but remember the experience you had with your truck. 

Good Luck
John Shurtz
John & Kathi Shurtz
2005 Patriot Thunder
42FT Vicksburg 525 CAT
1996 36FT Monterey