kortan01 Report post Posted January 15, 2015 At 22k miles, I've noticed that our '13 DSDP tires are all wearing flat and even all around, with only minor edge wear on the tag axle tires and the steer tires. However, the drive tires are wearing more than the other tires as evidenced by the small grooves (or lack of) on the Michelin tires. I've been told that this is normal since the drive tires are "working" under load at all times pushing the beast down the road, but I'm a bit suspicious of that. I would expect the steer tires to exhibit the most wear. Any thoughts? Share this post Link to post Share on other sites
dickandlois Report post Posted January 15, 2015 What are the weight numbers for the four corners with the tag axle up and down for all four corners ? What are the axle load weight numbers from the coach chart? Rich. Share this post Link to post Share on other sites
wolfe10 Report post Posted January 15, 2015 And, along with Rich's questions, what PSI are you carrying? Share this post Link to post Share on other sites
hermanmullins Report post Posted January 15, 2015 As Brett asked what are your tire pressures. Where is the most wear, Center or Outer Edge? Too much pressure and the tires will wear in the middle of the tires while too little pressure will result in outer edge wear. Also too little pressure in the tag axle will reduce the wear on the tag tires and increase the wear on the drive tires. If you can have each axle weighted then you can have the correct pressure set for the tag. Brett or Rick, do either of you know where kortan01 may find the chart for calculating tag axle pressures? Herman Share this post Link to post Share on other sites
dickandlois Report post Posted January 15, 2015 Herman ! This might be a good issue for House Calls and Gary B. looks like there is a number of different setups used by coach builders using tag axles Here is a link to an addendum published by Monaco for The Executive & Dynasty 2001. http://www.icbus.com/staticfiles/monaco/manualaddendums/2001/tag_axle.pdf This is a link to some information on the FMCA forum. Although it is not directly related to the OP question. http://community.fmca.com/topic/1924-weight-on-tag-axle/ Also some information hear. http://forums.trailerlife.com/index.cfm/fuseaction/thread/tid/26254515/print/true.cfm Mobile Weight Station link. Services. http://rvweigh.com/ourservices.html Good year tire pressure information for RV weight(s) http://www.goodyearrvtires.com/pdfs/tire-care-guide.pdf Tiffin RV Tag Axle information http://www.tiffinrvnetwork.com/crusingator/ABfyi/FYI-052.pdf Precision frame Tire and pressure information http://www.precisionframe.com/articles/TireSafetypart1.pdf Michelin Tire and Tag Axel information. https://www.michelinb2b.com/wps/b2bcontent/PDF/RV_Tires_Brochure.pdf Newell uses 25psi in there tag axles on most models and they do not lift them off the ground in many models, just go to 0 psi. Rich. Share this post Link to post Share on other sites
tireman9 Report post Posted January 21, 2015 Drive tires do wear because they are "pushing" all the time. If you have a TAG axle then the tires are also being dragged or pushed around each turn or corner. Here are the details. If you think about it, a car has all 4 tires rotating around a centerline that is "pointing" to the center of the turn radius. Many years ago car manufacturers discovered how to design front suspension geometry to include something called "Ackerman". Here is definition that explaines what it is. Ackerman addresses the front end and solid axle rear ends basically have the centerline of the axle pointing at the center of the turning circle If you add a 2nd rear axle or "TAG" and project the centerline of that axle, clearly it can't be pointing to the same center of the turn as the drive axle is. This is one of the reasons multi axle RV trailers have such short tire lives. Now large 22.5 TBR tires don't flex like smaller 15" or 16" trailer tires so the large tires are forced to slip (wear) If you want to learn more about Ackerman there are some videos on YouTube. or here Share this post Link to post Share on other sites
