Tire Safety System

[garyde]

Me too Cosmo!

The cats out of the bag!

[Jon Wehrenberg]

Gary,

You should include your tires in your pretrip inspection and give them a really good look. We learned this the first trip. The tags were scalloped a little around the edges, but there was plenty of tread. I never gave it a second thought.

It turns out the tags will eat themselves up in very few miles if things are not right. They did. If you have a tire problem, with your tire sizes my guess is you will be parked for quite a while. All it takes is one experience thousands of miles from home to make you a believer.

[Orren Zook]

Gary,

You should include your tires in your pretrip inspection and give them a really good look. We learned this the first trip. The tags were scalloped a little around the edges, but there was plenty of tread. I never gave it a second thought.

It turns out the tags will eat themselves up in very few miles if things are not right. They did. If you have a tire problem, with your tire sizes my guess is you will be parked for quite a while. All it takes is one experience thousands of miles from home to make you a believer.

Jon,

Were you able to determine the cause of the accelerated wear? Bushings, inflation, alignment??? I have had my alignment shop say that front tire wear can also be caused by worn bushings on the drive axle. I had seen this on trucks, mostly with the Hendrickson suspension where you can watch the axles track in and out when throttle is applied or lifted - but had not given much thought to the conditon of the the suspension bushings on the drive axle of my bus because of the low mileage.

[Jon Wehrenberg]

Scalloped edges was a common problem on 12R 22.5 Michelins in the early 90s. When I got the coach there was slight scalloping that was blamed on balance or alignment (according to the genius tire guy).

I had the front tires with the scallops placed on the tag because of advice from the tire dealer, had the tags moved to the front and the fronts balanced with weights and the front aligned. The coach was almost new so wear was not an issue.

As it turns out the advice about moving the tires to the tag was lousy. I now know if you want to straighten out a tire problem the tire needs to be on the drive axle. But thinking we were OK we left for our first long trip and after about 4000 miles I found the tag axle had enlarged the scallops right down to the steel belts on one of the tires. I later learned that tag axles are notoriously hard on tires, especially if they already have a problem and are out of balance. The last time I listened to advice on tires was from the guy that changed my tires. BTW, on the next set I had the coach re-aligned, and I used Equal to balance them, and I rotated them every 30,000 and they had 1/4 of tread on them when I replaced them at 130,000 miles.

[gmcbuffalo]

I was told my a manager at Les Schwab that tire scalloping is common on any floating axle. ie steers and tags.
GregM

[garyde]

Yes, thanks Jon. The curious thing about the tag is the wear. When I was in my 20's, I owned VW Buses. Those tires on the back transaxle wore on the outside edge too. I don't really understand why on a strait axle I would see edge wear. My Country Coach tag was the same.

[Jon Wehrenberg]

As Greg points out the "floating" tires are very susceptible to irregular wear patterns. Some tires are made specifically for these axles and some are made specifically for drive axles. I do not know the dynamics that creates that situation.

On the coaches that used 365 tires on the steers and tags, and 315 on the drive tire care is more critical than ever. When I had a tire wear issue I could simply place the tire in question on the drive axle and that unusual wear pattern was corrected over a period of time. Because of the steel inner wheels on 45 foot coaches or because of a wheel polishing issue doing that involves breaking down the tires and wheels, but at least you could salvage a very expensive tire when its wear was caught promptly. That option is not available on coaches with dissimilar tires so checking pressures and feeling for any wear problems becomes critical.

With the price of 315 tires now north of $600, I think a tire monitoring system that works should almost be standard equipment on the shells. I also think it should be the band type so there is no added potential for leaks, and I also think the battery life in the sensor should be five years to parallel the life of the tire. As long as I am bloviating I also think the sensors should display actual tire pressure and not just a low pressure warning.

[truk4u]

That's the beauty of Smart Tire, temperature and pressure at the push of a button.

[JIM KELLER]

Jon, This tire talk has made me curious about my tag axel function. I always lift it in tight turns but notice it never clears the ground. The bus squats down on the suspension and I deposit less rubber on the cement but the tire still drags. I suppose lifting the tag reduces the side pressure on the wheels so that by itself is a benefit. Is there a height adjustment that will make the tag axel tires clear the ground ? Seems like 40 footers clear the ground with no problem and 45's just squat down.

99 Country Coach 45XL

[Joe Cannarozzi]

The drive axle is slow to respond to the additional weight when you lift the other. The drive bags will first squat but will come back up and If given enough time the tag will completly clear the ground on our bus.

I think that completly up is for sure the best senerio, merily dumping the weight and not lifting is still prefferable and makes a huge difference.

Nobody is gonna wait every time they make a turn and I don't think that is what the designers had in mind.

Train yourselves to use this option frequently, it will save you money.
Most turns at intersections on secondary roads I dump it.
Whenever we pull into a campground I have got into the habbit of dumping the tag as the first step in dropping the toad. By the time I get done its off the ground. I also dump it on the way INTO the fuel island and truckstops.
We also leave the house and take it a couple of blocks to the main road on 2 axles. There are 4 bags on the drive axles thats double whats nessesary.