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Tire pressures one more time

Yahoo Message Number: 9290
OK, I'm brand new here and have been reading the posts on tire pressures. My local T/A Truckstop scale won't allow me to weigh the vehicle side to side, etc. Sooooo . . . as a general rule, having a 42' Magna, full of diesel, water, and personal things that weigh it out at a little over 44,000 lbs., what, IN GENERAL would you be running tire pressures at with 315/80R X 22.5 tires? I have loaded it as evenly as I can for weight distribution. What in the fronts, duals, and tags?

Re: Tire pressures one more time

Reply #1 –
Yahoo Message Number: 9299
We would need to know the weights on each axle to tell you anything close to what you need. It's even better to have the weight on each wheel but you can only get that at an FMCA rally. We have a 40 foot 2001 Magna that has a weight of 42,000 pounds and we run our front 315 Michelins at 110, our Toyos on the drive axle at 105 and our toyos on the tag at 95. That gives us a good safety margin to loose a little air without always running somewhere to add air. We usually only add air at home or Lazy Days. Keep in mind that the 315 tires only have a speed rating of 65mph and on the Michilens the speed rating can be increased by adding 10 pounds of air over what your weight calls for. Thats why we run 110 in the front. We can run at 95, but I like the safety margin and the higher speed rating. Don't know about the speed rating on the Toyo 315s. At the FMCA show I asked Les Swab about the speed rating and they said toyo was going to raise it to 75 but the Toyo people say that will not happen. So the next time you are running at 75mph keep the speed rating in mind. It is in the tire books in small print at the bottom of the page. If you are not sure run the tires at 120 until you get a 6 point weight and recommendions from the scale people, or CCI people at a CC rally.

Bill G. 2001 Magna #5998

Re: Tire pressures one more time

Reply #2 –
Yahoo Message Number: 9300
Hi Folks,

Let's look at this tire pressure from a different view. For the lightest vehicles - the 32 footers, there is great latitude in pressure selection (from 55psi up to 120). As the coaches get longer and heavier, selection gets less, and for 40 foot and up, the selection goes to one - 120 psi. Here is the logic, on light coaches with tire pressure increases, the tire speed rating goes up, for heavy coaches, the speed rating stays at the maximum advertized by the manufacturer or is even less. New tire designs are needed for these heavier coaches to provide a margin for safety. CCI has struggled with the tire problem with costly recalls, changing tire size between front and back but results have been questionable. Eighteen wheelers were designed to overcome the tire load carrying limitation.
Fred Kovol

2000 Allure 30593

Re: Tire pressures one more time

Reply #3 –
Yahoo Message Number: 9301
Quote from: Glen Gieg
OK, I'm brand new here and have been reading the posts on tire > pressures. My local T/A Truckstop scale won't allow me to weigh

the

Quote
vehicle side to side, etc. Sooooo . . . as a general rule, having

a

Quote
42' Magna, full of diesel, water, and personal things that weigh it > out at a little over 44,000 lbs., what, IN GENERAL would you be > running tire pressures at with 315/80R X 22.5 tires? I have loaded > it as evenly as I can for weight distribution. What in the fronts, > duals, and tags?
Heres what I did to get the correct tire pressure. We both live in Oregon. Go into a weigh station that is closed. The scales still work and there is a digtal readout of your weight. Weight the front axle, then the rear axle with the tag down. Call Les Schwab in JC and they will give you thier recommended tire pressures. Be sure your coach is loaded normally, water and fuel full. Gary Wallstrom 03Magna 42ft 6251

Re: Tire pressures one more time

Reply #4 –
Yahoo Message Number: 9302

CC told me that the best method is to weigh each wheel location and then use the Toyo chart. Until that's possible, they suggest 125# in the single fronts, and 100# in each dual and in the tags.

Re: Tire pressures one more time

Reply #5 –
Yahoo Message Number: 9303

It is interesting that CC recommended 125 & 100. When they looked for the source of handling problems on my 03 36' Allure their solution was to lower the pressures to 75#. Just prior to leaving on our second 2500 mile trip a few weeks ago we had the Toyos replaced with Michelins. The tire shop reccommended 110# front and rear. I'll go with a good tire shop vs. CC or a toyo chart.
Doug Allure 30929

Re: Tire pressures one more time

Reply #6 –
Yahoo Message Number: 9306
Look up Toyo on their web site, it contains recommended air pressures. TWI 11731 Intrigue 2004 Ovation

Re: Tire pressures one more time

Reply #7 –
Yahoo Message Number: 9311
Fred, I guess I'm missing something. I don't understand what the length of the coach has to do with tire pressure except for the weight issue. It seems to me if you have all points weighed you can go by the tire mfg's chart based on the heaviest load on each axle. I add a little for future weight variations.
I had a 2000 Intrigue involved in the tire recalls (an early 2000) and recommended 120psi tire pressure all around, and the coach rode like a farm wagon at that pressure. Also, the tire recalls had to do with weight distribution on the front wheels which was alleviated by re-configuring the ride height valves. In addition, the tire recall was to replace the Toros WITH THE VERY SAME TOROS. I believe the speed rating on the 12x22.5 tires on my 03 Allure is 65mph, which is the speed I drive on the highway, although I can't find this rating in writing anywhere. A check with the local Toro dealer this AM confirmed 65-70 being reasonable. I can't believe that the occasional burst to 70mph is putting us at unacceptable risk. As I have said before on this board, my coach has ridden superbly at the tire mfg's recommended pressures, and I believe that's what the CC design people aimed for.
It seems to me that the use of a given tire mfg's inflation chart and watching Smart Tire for unusual tire temp's is the way to go for safety. tire wear and riding comfort. In my opinion, the recommendation to carry the maximum pressures is coming from legal dept's, not from the manufacturers.
The thing I like best about this board is the divergent opinions it generates.

Walt Rothermel
03Allure30811

Re: Tire pressures one more time

Reply #8 –
Yahoo Message Number: 9312
Quote
It seems to me that the use of a given tire mfg's inflation chart and > watching Smart Tire for unusual tire temp's is the way to go for
safety. tire wear

Quote
and riding comfort. In my opinion, the recommendation to carry the

maximum

Quote
pressures is coming from legal dept's, not from the manufacturers.
Walt, I think you're on to why we can't get good answers from the manufacturers. Whatever they recommend, someone is going to have a problem (likely nothing to do with the recommendation). And since we're currently in an "it's not your fault" society, some lawyer will sue whomever gave whatever advice.
I grew up in the Netherlands, and when someone slipped over a banana peel, most people would think (and some say): Why don't you pay more attention to where you're walking (they do have more derogative terms:-). Here in the US, the attitude is more like: Who's the person who did this, so I can sue him/her, or worse, what business is close by and why aren't they keeping there driveway clean.

Quote
The thing I like best about this board is the divergent opinions it

generates.

Here you have another one...

Re: Tire pressures one more time

Reply #9 –
Yahoo Message Number: 9314
I see where some people run Toyo's on the rear and michelins on the front. I would like to understand the reason for this before I purchase new tires.

Thanks

Vaughn 99 Intrigue 10809

Re: Tire pressures one more time

Reply #10 –
Yahoo Message Number: 9320
Vaughn,

Because Toyos handle poorly but they are cheaper. Michelin or Goodyear all around is the best choice.
Doug Allure 30929

Re: Tire pressures one more time

Reply #11 –
Yahoo Message Number: 9321
We recently had a problem with a Toyo tire and they were extremely helpful, warrantied the tire fully even thought it had 19,000 + miles on it because it was defective. We were told by service at CC that we were lucky that we didn't have Michelin's because they are very poor on customer service and defects in a tire. We also had a coach with GoodYear tires and had two blowouts (one on the front and one of the dualies). So we feel it is a matter of preference as to what tires you run. We have had Toyos on 2 toyotas and 3 CC and they have been fine. We have never felt a need to put steering tires on our CC. Dale Hollick 05 Affinity 6370

Re: Tire pressures one more time

Reply #13 –
Yahoo Message Number: 9324
-Doug, I want to understand and not pick a fight here, sooo, if Toyos handle so poorly why would CC use them and risk the rep of the coach to poor handling tires? If you are so inclinded, there are a couple of

other RV forums that seem to think that Michelins have a bad rep for not holding up / blowouts etc. Michelin always disallows the claim and

blames the coach owner. I have run Toyos on my pickup and car for 3 years no handling problems there, not a motor coach I agree.
I'm new to the CC but the Winnebago I traded had Michelins on it and I was never happy with the way it handled, sidewalls to soft always felt like a low tire.

So is the Toyo handling something you noticed or popular theory? Thanks for listening
Larry

'99 Affinity

Re: Tire pressures one more time

Reply #14 –
Yahoo Message Number: 9326
According to my goodyear tire manager, goodyear is the last thing you want if you travel in the southwest, he has the highest return % in the west. He prefers Bridgestone, but says Michelin is the best if you can get them adjusted in case of problems. TWI/CAROL 11731 Intrigue. Plus the steer tires cannot be rotated to the rear and vice versa.

Re: Tire pressures one more time

Reply #15 –
Yahoo Message Number: 9335
Larry

We have lumber trucks and have had dump trucks. On the trucks that don't routinely travel at highway speeds, i.e. dump trucks on local runs, the strong Toyo sidewalls are an advantage and the handling is not so important.
On road trucks traveling at higher speeds, not off-road much, we avoid Toyo's on the front due to poor steering. We aren't a big organization, but do base that on a few million miles of experience.
Since we replaced the tires and had the front aligned at the same time, we don't which helped the most. We suspect the alignment may have been the biggest factor since it was out as far as the shop had ever seen. I'll post a more complete description of the handling problems and how CC and Guaranty failed to deal with it soon.
Doug

Re: Tire pressures one more time

Reply #16 –
Yahoo Message Number: 9355
Marshall;

I run Bridgestones on the front and Michelins on the rear. Does a pretty good job, even when the wife is cruising at 70mph.
Steve

95 Magna 5220

"C. Marshall" wrote:

Re: Tire pressures one more time

Reply #17 –
Yahoo Message Number: 9358
Vaughn,

We run Michelins on the front because CC put them on at my request when we wore the toyos out in 10k miles. We like the Michelins enough to order them all around on our new 2005 Magna at an extra cost of at least $1000. The 315 Michelins CC put on our 2001 Magna are steer tires and they ride much better then the Toyos.

Bill G. 2001 Magna #5998
 

Re: Tire pressures one more time

Reply #18 –
Yahoo Message Number: 9376
Thanks Bill, My coach came with Toyo"s so I don't know the difference between one tire and another as far as safety and handling characteristices go.

Vaughn 99Intrigue 10809