Tire Replacement

[Jon Wehrenberg]

Peter,

Serious question along these lines.

Do you change your ELT battery at the date required or have you analyzed it and determined if you do not use it you can get a few more years out of it?

We both know the battery is a long way from dead on the manufacturer's date for replacement.

(For non pilots that is the battery in the Emergency Locator Transmitter on a plane and like our tires the manufacturer puts a date, and replacement is two years.)

[Petervs]

Yes Jon, I do change the ELT batteries by the date required. I have 5 ELT's since I have 5 airplanes ( well 2 belong to my kids but I seem to maintain them...). But that is a federal law. It was originally based on the idea that the batteries should be changed when the expected output was 80% of new. Newer ELT's use better batteries ( plain Duracells) that require changing only every 6 years or so instead of 2 years on the old ones. And if you cut up a current "Old" style ELT battery, you will find 6 modern Duracell AA potted together in a package, that's all. Those potted units require 2 year replacements, the ones that use the Duracells loose can go 6 years. I wonder if the ELT battery companies really want to extend the useful life?

I wonder if the tire companies really want to extend the useful life of tires, or if they would rather just sell more and more tires to those gullible enough to pay for them? Of course they would rather have the sales and the reduced liability.

Changing tires at some arbitrary date is just a sales job gone overboard. When this business of motorhome tire replacements first got going it was 5-7 years. Now it is just 5 years. Maybe soon we should do it annually?

[rff105]

Just received some tire quotes we have some uneven tire wear in the front end and the right side drive tires are worn more than the left side which look brand new. The bus pulls a good amount to the right even on flat road with no crown. So we are looking at getting an alignment putting two new 365s on the front changing out the 2 old drive 315s and putting the best two of the four 365s on the tag.

New tread depth on XZA 365/70R22.5 is 19/32
New tread depth on XZA1 315/80R22.5 is 18/32
All tread measurements are not taken to wear bars and in the center of tires. Take 2/32 off each tire for wear bars.
Steer – Driver (12/32) Pass 11/32)
Drive – Driver (Out 16/32)(In 17/32) Pass (In 7/32)(Out 8/32)
Tag – Driver (13/32) Pass (11/32)

Could the slightly larger drive tires 17/32 vs. 7/32 contribute to the pull to the right? Would you mix the new drive tires with the old by putting the 2 new on the outsides, or just put the new set on the passenger side duels because it seem like that side wares faster due to road crown?

Michelin XZA 365/70R22.5 are $630 tire only, 6 week backorder
Michelin XZA1 315/80R22.5 are $605 tire only, 8 week backorder

This bus only has 30,000 miles on it seems like a lot a tire wear from reading other post here where age comes into play long before tire wear.

[rbeecher]

Richard,

I could be off on this one but my thinking is that I would weigh the coach without any personal stuff on board and maybe just the fresh and fuel tanks full.

I'd want what we refer to in the racing world as a corner weight check but I'm not sure there is a way to get that sophisticated with a bus. I'm sure someone here can give you the best procedure. I would want to know the axle weights at minimum with tires properly inflated and then I would have the alignment checked and get a before and after printout.

You could have bent rims or be in need of shock replacements.

My 2 cents, hopefully others will chime on with their thoughts.

Richard Beecher
2002 Marathon XLII
1996 Vogue for sale

[rff105]

Here is a picture of the Right Front. Looking at the picture the left side is the outside (picture taken from the front looking back). The inside 4 ribs look OK with even wear. The outside 2 ribs are worn slanted with about a 1/4" jump between the 1st and 2nd rib where you see the shadow from the dust on the floor in the garage.

[jack14r]

Last year I had my 2001 XLII aligned at Prevost Nashville.The technician and I talked during the process,the caster,camber and the toe in were off,the tag was off and the drive was off also.The technician told me it had never been aligned based on the type of shims that were used,he also said he had seen several new shells that arrived in Nashville from the factory that needed tires because of the factory alignment.I can't tell you how well it drove after the alignment,fuel mileage increased 1 MPG and a rumble that was present about mid coach went away.Before the alignment I had some tires that looked bad also.Jdub has the alignment data now because he owns the coach now,maybe he can post the data.

[Jerry Winchester]

Now it only rumbles when you drive it under 85 MPH. Never buy a coach from a race car guy.

I'll dig up the data when I get to Oklahoma this weekend.

It drives perfectly.

[rbeecher]

Now it only rumbles when you drive it under 85 MPH. Never buy a coach from a race car guy.

I'll dig up the data when I get to Oklahoma this weekend.

It drives perfectly.

Ahhh, JDUB,

After meeting Jack at a race in Virginia last year, I'd say buying a coach from a race car guy is the only way to go.

Come to think of it, we bought our XLII from a race car guy.

Richard Beecher
2002 Marathon XLII
1996 Vogue 40 for sale

[BrianE]

After listening to the 5 year replacement argument for as long as I've been here (4/06), I decided to check up on A-1's facts. The ELT example tore it for me. Come on Jon, talk about apples and oranges. Sheesh!

While we all respect Jon's conservative approach, in most cases he can verify his info, it's time for a little challenge.

It's very possible that the 5 year "rule" is well documented in fact but I sure can't find it on the internet. What I WAS able to verify is that the Michelin Warranty I found states that some of their tires are warranted to 5 years. Many of their truck tires have a 700.000 mile 7 year warranty. Nowhere does it recommend tire replacement in 5 years. Additionally, after reviewing the Prevost maintenance manual and service instructions I could find no reference to tire replacement based on age. Donde es el poop?

In checking Michelin's publications I found the following brochures: http://www.michelinrvtires.com/miche...e-material.jsp. Would suggest that a review of their Warranty also Service Life for RV/Motorhome Tires booklets would be helpful. Finally, as an added nail in he 5 year coffin is another brochure put out by Bridgestone. http://www.trucktires.com/bridgeston...V_Brochure.pdf. Page down to the heading "How Old is Too Old"

Also did a little research into warranties and other info. Bridgestone and Firestone both offer a 6 year prorated warranty. Goodrich's is 4 years, Goodyear's is 5 years and Michelin of course is 5 on the size tires we run on our busses. The availability of 12Rx22.5 tires seems to be dwindling for the tire treads we prefer in our coaches with Michelin XZ2, Bridgestone R250F, Goodrich ST230 and Goodyear G149RSA's as other choices. There seems to be more choices in the larger tires and Prevost issued a Service Bulliton M104-11 which recommends the Michelin XZA2 as their best choice. Hope this helps.

Prices seem to jump all over the place. Peter has made the observation we need to try and cut out some of the middle-man money on our tires. Any ideas?

[JIM CHALOUPKA]

The following link leads to more opinionated information to help a tire user make his/her own decision on the tire age/life issue.
http://www.tirerack.com/winter/tech/...jsp?techid=138