jblick626 Report post Posted October 1, 2013 Help, We are here in the Dallas are and we have a 99 Diplomat that needs tires. The size presently on the coach (all around) is 225 70R 22.5, but looking at the Michelin program and calling around to a few of the big truck tire shops no one seems to have the exact size available. One service center said the size is no longer manufactured, and they are looking for one size larger the 235 70R 22.5, and haven't found anything yet. I looked at using the 255 70R 22.5, and the height (diameter) will be close, but the added width will not fit in rear wheel wells when the coach is off of the airbags. One RV repair facility said to use the larger 255 70R 22.5 and they said it is OK for the coach to rest on the tires when it is stored, but my fear is if I'm trying to level the beast and it tips the coach up and down on the tires it will eventually cause a problem. I called Monaco Tech Support in Oregon, and they only show the one size tire that is acceptable for the coach, the smaller 225 70R 22.5. Any suggestions? Thank You Share this post Link to post Share on other sites
wolfe10 Report post Posted October 1, 2013 jblink626, Welcome to the FMCA Forum. Look at your GVWR sticker which is generally near the driver's area. It will state the correct OE tire and rim as well as pressure if each axle is loaded to GAWR. Let us know what the OE tire and wheel size are. Brett Share this post Link to post Share on other sites
tbutler Report post Posted October 1, 2013 I looked at using the 255 70R 22.5, and the height (diameter) will be close, but the added width will not fit in rear wheel wells when the coach is off of the airbags. One RV repair facility said to use the larger 255 70R 22.5 and they said it is OK for the coach to rest on the tires when it is stored, but my fear is if I'm trying to level the beast and it tips the coach up and down on the tires it will eventually cause a problem. I called Monaco Tech Support in Oregon, and they only show the one size tire that is acceptable for the coach, the smaller 225 70R 22.5.Any suggestions? Thank You Regarding the width of tires on the rear axle, the spacing between the dual tires is critical. Using larger tires reduces the spacing between dual tires. The spacing accomplishes two things. There must be sufficient space between the dual tires to allow air for cooling the tires during operation. If there is insufficient space between tires air circulation will be limited and the tires will be more likely to overheat. Also, tires bulge when they come in contact with the pavement. If the two tires "kiss" there will be extreme tire wear and the tires will be destroyed by the friction and heat that results. If the tires barely fit the wheel well I would be very concerned about the spacing between the dual tires. Share this post Link to post Share on other sites
kaypsmith Report post Posted October 2, 2013 If 225 70R 22.5 is the correct size, as stated by the dealer and the oe size located as Brett says. Here is a link, I hope that no one thinks that I'm pushing anyone, but this has advertised Michelin, and appears to be fmca approved dealer. http://www.dickmantires.com/tiresbysize/22570195info.html That size fits 6.00 to 6.75 rim, and is used a lots in China, and on some trucks such as Hino. Good luck in your search, Kay Share this post Link to post Share on other sites
Walt2137 Report post Posted October 27, 2013 Help, We are here in the Dallas are and we have a 99 Diplomat that needs tires. The size presently on the coach (all around) is 225 70R 22.5, but looking at the Michelin program and calling around to a few of the big truck tire shops no one seems to have the exact size available. One service center said the size is no longer manufactured, and they are looking for one size larger the 235 70R 22.5, and haven't found anything yet. I looked at using the 255 70R 22.5, and the height (diameter) will be close, but the added width will not fit in rear wheel wells when the coach is off of the airbags. One RV repair facility said to use the larger 255 70R 22.5 and they said it is OK for the coach to rest on the tires when it is stored, but my fear is if I'm trying to level the beast and it tips the coach up and down on the tires it will eventually cause a problem. I called Monaco Tech Support in Oregon, and they only show the one size tire that is acceptable for the coach, the smaller 225 70R 22.5. Any suggestions? Thank You I had a 99 diplomat and the 255/70 22.5 is what came on the coach from Monaco factory. As has been stated look on the wall behind the driver seat at the GVWR sticker. On our 38 ft coach and the best I remember all length diplomat that year had a 10,000 front axle and with the 255/70 you need a min of 105 psi for 10,000, I installed 275/70 22.5 Toyo's all the way around on our coach and the only problem I had was the left rear skirt I trimmed 1/4 inch off the inside of the skirt because it was a little to close. I just used painter tape and a jig saw. I think if you would check a pressure chart on the 235/70 I am sure you will see that you are overloading the front tires of the coach with a load of water and fuel with driver and copilot and not a lot of stuff in the bay you are maxed out on the front axle. The rear is 19,000. Walt 2000 Dynasty F191141 Share this post Link to post Share on other sites
wildebill308 Report post Posted October 28, 2013 I would recommend you call and talk to Cowser Tire&service. They are knowable and I believe they participate in the tire program. http://commercial.cowsertire.com/ Bill Share this post Link to post Share on other sites
jblick626 Report post Posted October 28, 2013 Hi Everyone, Thanks so much for the reply's regarding the tire size. I have been out of town on business and my laptops doesn't allow non company site access so I have been limited on my ability to respond. However, I did make contact with tech support in Monaco Oregon, and he took the time to look up the coach information with the VIN number and he said that indeed I can use the 255/70 22.5 He was not sure why the tag was not updated in the coach, so he is sending a new one with the updated info. Thanks again for all of the help !!! Share this post Link to post Share on other sites
Mikefpt Report post Posted November 4, 2013 I have a 2006 diplomat and replaced with slightly larger tires for the same reason. Everything fits great. There is minimal difference in the actual size. The tire company stood them side by side when mounted and inflated. Maybe a quarter inch difference in height and width. With bags deflated it rests on tires but when stored I lower rear jack so frame comes slightly off tires. When parked it is leveled anyhow and is always off the frame. No problem with rubbing front wells with complete turn in or out. Also talked with monaco rep and he agreed that the difference is minimal. Now trying to figure out proper inflation. Share this post Link to post Share on other sites
Mikefpt Report post Posted November 4, 2013 Also bought Hankook tires. Great ride, great price. Michelin program much more expensive. Share this post Link to post Share on other sites
2zdirt Report post Posted December 12, 2013 Hello Eveyrone, I have a 2000 Diplomat. It needs tires. I am trying to find out what my options are with tire sizes. Current tire size is 255/70R 22.5. What size tire came on your 2006 and what size did you end up with? Thanks! Share this post Link to post Share on other sites
racer478r Report post Posted December 15, 2013 I replaced the tires on my 2000 Diplomat from the original 255x70x22.5 to Bridgestone 275x70x22.5. Much better ride. Share this post Link to post Share on other sites
wolfe10 Report post Posted December 15, 2013 Yes, some can go up in size. But, need to check for correct rim width for tire, adequate dual wheel spacing and clearance to body and suspension parts. It will also affect effective axle ratio and speedometer. Share this post Link to post Share on other sites
Monaco2000 Report post Posted January 21, 2014 What did you end up doing? I also have 225s for some reason on my 200 diplomat.....bought it that way.....are the 255s available?? I don't want to have to "trim" pieces off my bus to make tires fit....if 255s are the tire from the factory then 255s should still be the best choice.....are they still in production? Share this post Link to post Share on other sites
wolfe10 Report post Posted January 22, 2014 Yes, both 255/70R22.5 and 255/80R22.5 are available. Share this post Link to post Share on other sites
Walt2137 Report post Posted February 9, 2014 What did you end up doing? I also have 225s for some reason on my 200 diplomat.....bought it that way.....are the 255s available?? I don't want to have to "trim" pieces off my bus to make tires fit....if 255s are the tire from the factory then 255s should still be the best choice.....are they still in production?The tires that came on the 2000 Diplomat were 255/70 R22.5 Go here for the info on your coach and click on the 2000 Diphttp://www.monacocoach.com/monaco/brochures.html Share this post Link to post Share on other sites
