| Author | Message | ||
| Jim Wilkerson (Wagwar)
Registered Member Username: Wagwar Post Number: 46 Registered: 12-2009 Posted From: 12.158.159.60 Rating: N/A |
I'm trying to understand the difference between an 11R 22.5 tire, 12R 22.5 and 315R80 22.5. From the archives, it seems that the 11R is more commonly available in the boonies than the 12R. The 12R has a higher weight rating. However, what is the aspect ratio on an 11R and a 12R? Is it a 75? 80? 85? is it basically the same as the 315R80? Are there 'low profile' 11R's, high profile 11R's etc? Is an 11R 22.5 interchangeable with a 315R80? If I just ask for "an 11R 22.5 16ply" will I get the right steer tire for my bus? | ||
| Sean Welsh (Sean)
Registered Member Username: Sean Post Number: 1057 Registered: 1-2003 Posted From: 72.171.0.143  Rating: N/A |
Jim, Which one of those three you need depends on what width your rims are, and how much weight you are carrying on that axle. There is no such thing as "low profile" in inch-size tires. The 11R will only fit on 8.25" rims. Most 315R require 9" rims. 12R will fit on either. If your bus came with 12R, it is possible 315R will not fit due to interference with tie-rod ends. You would need to test-fit one. 11R is a smaller diameter than 12R or 315R. 12R and 315R are similar diameter. If you change from 11 to either of the others, or vice-versa, your speedo might be off and/or you might have different top speed and low-end power. "Ply" is mostly a meaningless term. They are not standardized by any agency and are only useful within one brand's line. Use load range instead. Modern tires have at most five plies, by the way, so "16 ply" is a "rating" not a reality. Lots of material on this in the archives. If you tell us what tires you are replacing and what your axle weights are, I can give you more on what, specifically, will work for you. I don't remember what coach you have. -Sean http://OurOdyssey.BlogSpot.com | ||
| Bill Holstein (Billmoocow)
Registered Member Username: Billmoocow Post Number: 70 Registered: 5-2009 Posted From: 76.115.120.243  Rating: N/A |
Is the 11R, the standard on semi trucks hauling heavy loads? And, are they not less money? | ||
| Sean Welsh (Sean)
Registered Member Username: Sean Post Number: 1058 Registered: 1-2003 Posted From: 72.171.0.142 Rating: |
No, Bill, the most common tire on line-haul semis is an 11R24.5 (or its newer metric cousin), not 11R22.5, at least in the US. The 12R22.5 is probably the most common inch-size line-haul tire for the 22.5" wheel, which is the standard in most of the rest of the world. The most common truck tire size overall is the 295/75R22.5. 11R22.5 tires generally do not have the load capacity for class-8 service. -Sean http://OurOdyssey.BlogSpot.com (Message edited by Sean on April 06, 2010) (Message edited by Sean on April 06, 2010) | ||
| Bill 340 (Bill_340)
Registered Member Username: Bill_340 Post Number: 103 Registered: 7-2006 Posted From: 75.200.33.221  Rating: N/A |
This may help with size difference, We use it all the time Try http://www.miata.net/garage/tirecalc.html | ||
| Bill Holstein (Billmoocow)
Registered Member Username: Billmoocow Post Number: 71 Registered: 5-2009 Posted From: 98.232.207.25 Rating: N/A |
That is a cool calculator. The difference between the 12/22.5 and the 11/24.5 is 0. | ||
| FAST FRED (Fast_fred)
Registered Member Username: Fast_fred Post Number: 1137 Registered: 10-2006 Posted From: 69.19.14.21  Rating: N/A |
I would weigh the coach FIRST. Tires that are too big or built for a weight far above what your coach actually weighs will only cost more and give a rougher ride . I would look for tire Rolling Resistance FIRST in picking a brand , after you figure the type tires you need. ( see archives) On each tire mfg site is a table showing weight vs inflation pressure that gives best ride and longevity for each tire. Many folks will use "steer tires" on all positions to allow rotation to equalize wear . The Yokohama 617 are fairly low priced (compared to Michilen's) and might fit your ride needs. FF | ||
| Josh McElhiney (Zcommanager)
Registered Member Username: Zcommanager Post Number: 127 Registered: 1-2009 Posted From: 75.187.41.177  Rating: N/A |
FF: Since you mentioned tire rotation, I have to ask a newbie - perhaps stupid question. What is the rotation pattern for a duallie - i.e. '61 SDM? And what is the suggested mileage between rotations? I'm presuming it's greater than on a passenger vehicle?? Thanks, Josh | ||
| Justin Burie (Justinb)
Registered Member Username: Justinb Post Number: 17 Registered: 1-2010 Posted From: 209.254.23.194 Rating: N/A |
============================================ Quote = Sean No, Bill, the most common tire on line-haul semis is an 11R24.5 (or its newer metric cousin), not 11R22.5, at least in the US. The 12R22.5 is probably the most common inch-size line-haul tire for the 22.5" wheel, which is the standard in most of the rest of the world. The most common truck tire size overall is the 295/75R22.5. 11R22.5 tires generally do not have the load capacity for class-8 service. =================================================== I'm going to take some exception to your statement Sean. Having actively lived and breathed trucking in my profession over the past 17 years, a few things have changed on tire size specifications. 11R24.5 tires fell heavily out of favor in about 2000 - 2001. See comments below on why. 24.5 Lo-Pros (Low Profile ie 275/80R24.5 & 285/65R24.5) largly fell out of favor in the mid-90s as highway speeds crept up. 11R22.5 is a very popular profile for local, vocational & and regional haulers. Many Owner/Operators have changed their spec from 24.5Lo-Pro to 11R22.5. Air chamber size, casing value & rolling resistance are playing big parts in this decision. Lo-Pros are subject to funny wear patterns as heat build up in the smaller ir chamber at higher highway speeds. 1122.5 tires also match the revs/mile of the 455 series X-One super-single drive tires. 22.5 Lo-Pro (275/80R22.5, 285/65R22.5 & 295/75R22.5) aore the big player an all things linehaul & many things regional & local delivery. This commonality has much to do woth rolling resistance, fuel efficiency & casing value. Just dont try to run at 70+mph all day, every day & expect them to live. These 22.5" lo-pros also match the revs/mile of the 445 series super-single drive tires ala the Michelin X-One series. Rules of Thumb that have kept me out of trouble on truck mfg specing programs: "14ply" Rating 11R22.5 & 275/8022.5 singled out = 13,000#/axle "16ply" Rating 11R22.5 & 275/8022.5 singled out = 14,500#/axle "16ply" rating 12R22.5 singled out = 14,500# axle "18ply" Rating 315/8022.5 singled out = 16,000# (Also max allowed by many stated on tread width measurement enforcement) "20ply" Rating 315/8022.5 singled out = 18,000# (Capped at 16,000# max by many stated on tread width measurement enforcement) | ||
| R.C.Bishop (Chuckllb)
Registered Member Username: Chuckllb Post Number: 1211 Registered: 7-2006 Posted From: 75.243.148.70 Rating: N/A |
Thanx for the post, Justin! Great clarification and very helpful at the bottom! RCB | ||
| Sean Welsh (Sean)
Registered Member Username: Sean Post Number: 1059 Registered: 1-2003 Posted From: 72.171.0.143 Rating: N/A |
Justin, Thanks for the clarification. I realized after I made that post that someone with more current information was probably going to correct it. I do know that, as I stated, 295/75R22.5 is the single most common tire in use today. I had not realized that so many had moved away from 24.5" rims, though. I still see them on a lot of trucks. The problem for many buses is, of course, higher axle loads than line-haul trucks. This is why so many buses came equipped with either 12R22.5 or 315/80R22.5, which are pretty much the highest capacity single-width highway tires made. The newer Prevost conversions, running close to 54,000 from the factory, are extra-legal without the 315's on the drivers, and they've had to go to super-singles on the steer and tag axles. Most 45' seated coaches today have 315's from the factory. Our coach is very heavy, at 48,000, and we had a big push to change to the 315 several years ago, even switching out our 8.25" rims for 9" ones, because I wanted to run lower pressures. I finally gave up, as the 315's were costing a fortune, making it hard to steer at low speeds, and not really providing any other benefit. We're back on 12R22.5 now. -Sean http://OurOdyssey.BlogSpot.com | ||
| Debbie and Joe Cannarozzi (Joe_camper)
Registered Member Username: Joe_camper Post Number: 259 Registered: 10-2006 Posted From: 99.23.130.168  Rating: N/A |
I have pulled spread axle semi trlrs that are legal with 20000lb per axle and come from the factory with 11-22.5 rubber. That same configuration would be able to carry almost 25000lb before it got too heavy for the rating on a a set of 4 11-22.5's The 24 inch rims that come on tractors and trlrs are 12-24.5 those and 11-22.5 are currently the 2 most common tires in the trucking industry or at least that is what I have encountered. | ||
| Sean Welsh (Sean)
Registered Member Username: Sean Post Number: 1064 Registered: 1-2003 Posted From: 72.171.0.140 Rating: N/A |
Joe, that 20,000 lbs is spread across four tires, not two. Lots of buses are carrying 23,000+ on the drivers, and up to 16,000 on the steer and tag axles. So an 11R22.5 that's perfectly adequate dualed on a trailer axle may be underrated on a bus. Many 45' parlor coaches today come equipped with 9" rims (and stock 315/80R22.5 tires), and an 11R22.5 tire is not even an approved fitment on those rims. 24.5" wheels are generally fitted with 11" tires or their metric counterparts; I don't recall even seeing a 12" tire for these wheels. Lots of folks on this board can run 11R22.5 tires if they have 8.25" rims, but many of us can't due to weight. And while switching between 12R22.5 and 315/80R22.5 can generally be done without penalty provided there is no tie rod or fender well interference, switching between either of those and 11R22.5 will require a speedometer adjustment and will affect the acceleration and top speed of the coach, and it will lower the ground clearance. There are many factors to consider in a tire decision besides availability. Jim asked what the differences were among these tires, and specifically whether an 11R22.5 was interchangeable with a 315/80R22.5 (answer: not usually). As often happens the thread has diverted down the path of what tires are more common in the trucking industry, rather than answering the questions originally posed. Perhaps informative in its own right, as long as we keep in mind that the bus came from the factory with a certain size tire for a reason, and changing from the coach manufacturer's tire size recommendation should not be done lightly just to save a few dollars. -Sean http://OurOdyssey.BlogSpot.com | ||
| Douglas Wotring (Tekebird)
Registered Member Username: Tekebird Post Number: 440 Registered: 10-2004 Posted From: 71.57.224.23 Rating: N/A |
Cost: There is not that much difference other than the "extra" cost that some tire dealers might ADD becuase it is not something they have already paid for (STOCK) as for availability. Once again, I bet I can get a 12r22.5 tire in a rib/all position tread anywhere in the Cont. US within 1 day if needed. Carrying a spare will get you out of most tire failure situations Sure going to a "common "sized truck tire will open up your options as to brand and off the shelf availability ( walk in and pay the man to put it on right now) | ||
| Bill Holstein (Billmoocow)
Registered Member Username: Billmoocow Post Number: 74 Registered: 5-2009 Posted From: 98.232.207.25 Rating: N/A |
That what im talking about. Options! More options, bigger competition, lower the price. | ||
| Tom Christman (Tchristman)
Registered Member Username: Tchristman Post Number: 205 Registered: 1-2006 Posted From: 66.218.33.156 Rating: N/A |
Diameter wise, the 11R-24.5 is the largest, then the 12R-22.5 or 315/80R-22.5, then the 285/75R-24.5 low profile is the same as the 11R-22.5, then the most popular tire being used, the 295/75R-22.5 or 275/80R-22.5. I use 11R-24.5 on my bus since it is a transit and sits lower-I wanted it higher and better gearing. Good Luck, TomC | ||
| FAST FRED (Fast_fred)
Registered Member Username: Fast_fred Post Number: 1139 Registered: 10-2006 Posted From: 69.19.14.26 Rating: N/A |
"as long as we keep in mind that the bus came from the factory with a certain size tire for a reason, and changing from the coach manufacturer's tire size recommendation should not be done lightly just to save a few dollars." I was told the main reason for using 12R22,5 instead of 11R22.5 was not the weight of the bus. It was to keep drivers from swopping wheels with a trucker to pick up a couple of bucks. ???? FF | ||
| Sean Welsh (Sean)
Registered Member Username: Sean Post Number: 1068 Registered: 1-2003 Posted From: 67.142.130.25 Rating: N/A |
I've heard that before, Fred. It's an urban legend. -Sean http://OurOdyssey.BlogSpot.com | ||
| Justin Burie (Justinb)
Registered Member Username: Justinb Post Number: 18 Registered: 1-2010 Posted From: 209.254.23.194 Rating: N/A |
RE: Steering Linkage & Fender Clearence With some care one can select the right off-set on a 22.5"x9" rim to make it all work. Setting the steering stops in the steeringbox can also keep the rubber from polishing dfferent parts of the bus. I do recall seeing photos of a 102" wide Eagle that had 385/65R22.5 floaters on the steer position. There is such a thing as a 12R24.5 tire. Usually used on equipment that goes "swampin' " on a regular basis. They're TALL! It's all about the footprint/contact patch with those things. | ||
| Jim Wilkerson (Wagwar)
Registered Member Username: Wagwar Post Number: 47 Registered: 12-2009 Posted From: 12.158.159.60 Rating: N/A |
Does anyone have experience they would like to share with the following tires or comments (Pro/Con)? Any manufacturers to avoid? All are Summer (vs All-weather) tires, 11R 22.5 rib-tread, all position, Load Range G unless marked otherwise and either rated 14PR or 16PR. Goodyear G287 and G288 Michelin XZA3 and XZE2 Remington R477 (steer) Remington R485 (Drive) Firestone FS560 16PR Load Range H Firestone FS560 14PR Load Range G HanKook AH 12 Toyo M122 Yokohama 103ZR Hercules (can't recall model) | ||
| larry currier (Larryc)
Registered Member Username: Larryc Post Number: 323 Registered: 2-2007 Posted From: 207.200.116.13 Rating: N/A |
I'd stay away from the Hercules, the Remington and maybe the Hankook although their top tire may be OK. I am not a Goodyear fan either. Go to a major tire service center and look at the weeks take off tires and their wear patterns. You can quickly decide what tires are wearing well and what tires have weak casing/wear issues. From the top, I like Bridgestone, Toyo, Yokohama, Michelin and Firestone. The rest all pretty much have casing and wear issues that stop me from using them, but you should go look at the worn out stack and make your own decisions. Generally the more I spend on rubber, the more service I get from it. I won't buy a "cheap" tire... Every tire I buy now days is over $500... | ||
| H3-40 (Ace)
Registered Member Username: Ace Post Number: 1027 Registered: 10-2004 Posted From: 75.248.112.131  Rating: N/A |
Well I had Goodyears on and they still look new. Only reason I removed them was they were dated 02. They have served me well since I bought the bus with a smooth ride. I just this week went and purchased 6 Cooper's at $445.00 each mounted, balanced and new steel stems! They appear to be a very good tire. I wanted to replace the Goodyears with the same but they were over $650.00 each for tire only! I also stayed with the original 315/80rx22.5 size. | ||
| Debbie and Joe Cannarozzi (Joe_camper)
Registered Member Username: Joe_camper Post Number: 260 Registered: 10-2006 Posted From: 99.23.130.168 Rating: N/A |
Next time you are at a truck stop walk up to a tractor and see what the 24.5's are. They will be 12 24'5 not 11.24.5 Every one of them | ||
| larry currier (Larryc)
Registered Member Username: Larryc Post Number: 324 Registered: 2-2007 Posted From: 207.200.116.13 Rating: N/A |
40 years in trucking and truck stops. Never seen the first 12.00 tire on a truck yet! I'll take a closer look next time I roll thru Chicago though, maybe it's a Chicago thing... After all, they gave us Obama. | ||
| George M. Todd (George_todd)
Registered Member Username: George_todd Post Number: 978 Registered: 8-2006 Posted From: 99.37.31.150 Rating: N/A |
Joe, The only set of 12R24.5 tires I have seen in the last two years are on Matt's MC6. They are Michelins, 10 years old, and now have 3000 miles on them. Larry, Lots of 12.00 22.5 tires on trucks, VERY VERY few 12.00 24.5s. G | ||
| Sean Welsh (Sean)
Registered Member Username: Sean Post Number: 1070 Registered: 1-2003 Posted From: 67.142.130.22 Rating: N/A |
Well, Joe, I stay in truck stops an average of three nights or so a month. We park with the trucks, and as a matter of curiosity I am always looking at tires. So I will say I've already done what you suggest, and I can state without equivocating that I see almost no 12R24.5 tires, but plenty of 11R24.5 (and metric cousins with essentially 11" treads). On the off, off chance I was completely misremembering, and "every one" of those tires was a 12R24.5 as you suggest, I went to all the commercial tire web sites to see what a great selection of tires there are in this size:
I stopped after these sites, because Bridgestone/Firestone, Goodyear, and Michelin together represent the majority of the truck tire market. But I believe I would find similar results on the other manufacturer's sites. By contrast, all these companies offer a selection of 11R24.5 line-haul tires in speeds up to 75mph. 12R24.5 is just not a line-haul tire. It is generally a severe-service (on/off road) heavy duty tire, speed-limited due to the heavy tread. Perhaps I can suggest your own advice: Next time you are in a truck stop, walk up to some tractors with 24.5" wheels, and see what shoes they have. I am betting you will find low-profile metrics or 11R24.5's, but not 12R24.5's. -Sean http://OurOdyssey.BlogSpot.com | ||
| FAST FRED (Fast_fred)
Registered Member Username: Fast_fred Post Number: 1140 Registered: 10-2006 Posted From: 69.19.14.28 Rating: N/A |
The Yokohama RY 617 come in fairly common sizes and seem to have almost as low rolling resistance as the big buck Michelins. Longevity ,,weather they will run , 150,000+ miles of life would hardly be a bus camper problem. FF | ||
| Tom Christman (Tchristman)
Registered Member Username: Tchristman Post Number: 212 Registered: 1-2006 Posted From: 66.218.33.156 Rating: N/A |
The only bus I know that used the 12R-24.5 was the gigantic (at the time) MCI-6. Most with the 6 have had converter plates made to change back to 11R-24.5 tires. While 12R-22.5 and 315/80R-22.5's are just about interchangeable, I would recommend staying with a normal truck tire. 11R-22.5 is a very common truck tire that most of us can use since we're not carrying as much as a loaded passenger bus. But the bottom line answer to that is to get your bus weighed in traveling mode with full tanks and everyone on board. Then you'll really know what tire to use. For instance, the 12R-22.5's that came on my bus are within a few hundred pounds capacity of the 11R-24.5 16ply that I'm running now. While the debate over what make of tire to use is just about endless, please remember that tires are much more then big round rubber things that hold up the bus. There is a good reason that Michelin are the most expensive tire-mainly because they are at the fore front of tire technology-meaning that Michelin usually makes the most new inovations. Then the other tire companies sit back to see if it works, and when it does, they make their own version. Like the super single X-ones. Personally, I run Michelins on all my cars, bus, truck, etc. About the best traction tire is the Michelin XDN2. Rides great, has unsurpassed snow and wet traction, and lasts a long time. Remember-with traction, it isn't only for acceleration or getting out of a mud hole, but more importantly is braking. I'd rather have a tire that may save a few feet in braking. That few extra feet maybe the difference between stopping before, or being impaled a couple of feet into the vehicle in front of you. That's why I run Michelins. Good Luck, TomC |
