When To Replace Tires

[arkietraveler]

I have Goodyear tires on my class A that were manufactured during the 4th week of 2010. They have good tread and 29k miles on them.

I've heard you might want to replace tires after 5 years even though they look good and have fairly low miles such as mine.

What say you?

[wolfe10]

After 5 1/2 years, I would have them inspected by a tire professional and go with his recommendation.

Like most mechanical things, their "care and feeding" has a lot to do with how long they will last:

Never overloaded

Never underinflated

Covered if stored outdoors

No signs of road hazards/curbing

[five]

What Brett said. The tread has nothing to do with replacement time. Most of us will age out our tires long before the tread is gone.

[hermanmullins]

Ditto on inspecting tires, always not just when they get past a certain time frame. Deep treads and beautiful and smooth side walls are nice, but you must look between the treads also. There is where you can find stress cracking. You can't see the cracks unless you get down and look between the treads.

Be safe, not sorry.

Herman

[tireman9]

Well I have to admit that I felt who could do a better job of taking care of their tires than I do?

I installed the tires new when they were only 18 weeks old. I installed TPMS and white tire covers in the 1st month of RV ownership.

I inflated them to +15 to +20 psi over the minimum needed to support the measured load on each corner of the RV. (My RV was very lightly loaded and Brett can tell you how small is was).

I have kept my travel speed down to 60-65 range. Never drove the RV below the inflation needed to support the load.

Never drove in Southwest and maybe the hottest I ran into was in Oregon the couple weeks after Redmond.

I had intended on following my own advice and do a "rolling" tire change (2 tires each year) starting at 7 years and selling the used tires.

BUT when I dismounted the tires to remove the original internal TPM sensors, I discovered that one tire from a dual position had severely stress cracks at the edge of the tread & sidewall so it had to be scrapped. The cause for the cracks was a slow leak last winter in it's mate resulted in it's mate to carry excess load, I believe that if I had used the RV I would have have discovered the low tire, fixed the problem (leaking valve core) and it's mate would never have been overloaded.

My main mistake was that I was over confident and didn't do the detailed inspection I should have done on the overloaded tire as it had what I thought was adequate air.

Clearly just looking at the tires while still on the RV, I had missed the cracks (outside edge of the inner dual). I clearly was over confident about the condition of my tires because of my care and that over-confidence lead to a less that complete, off the vehicle and even dismount inspection.

Because of my experience and looking at the costs of having a dismount inspection done every year I would suggest that people consider doing a "rolling change" starting at the 6th year of use for their tires. and if either tire is a dual position ever looses significant inflation both tires need a dismount inspection.

I have a blog post on the Rolling Change process. Now some will have some problems if they have special wheels or more than one size on their coach, but if you review the post I think you can develop a plan that will work for you.

Along with the purchase of 2 tires a year you can be sure to at least have an off vehicle inspection completed as a minimum as it will be much less expensive to address any issues discovered than rather than when on the road.

[rfsod48]

It is OK to replace (shift front tires) on one set of duals? It isn't necessary to replace both sets of duals at the same time?

[manholt]

Roger.

Here I thought I had everything tire, nailed down, and then instead of 5 to 7 years between tire change, your advocating 7 or 8 years in your blog. Also, yesterday, you said that a rolling change should happen at 7 years!

I understand the concept behind a rolling change. Confused about the 7 or 8 years, before you start. I for one would not trust my front tires for that length of time!

Carl

[hermanmullins]

Roland,

When changing tires on the rear duals it is best to change all 4 at the same time. Changing both tires on one side and then the others later can have problems on your differential. When you change all 4 at the same time all 4 have the same circumference. But if you change just one side there will be a difference in the circumference from one side to the other. Though the difference is only slight they will still put a strain on the gears and cause problems down the road. On steering or tags tires the difference doesn't matter since they roll independently from one another.

Herman

[rfsod48]

Herman

What you stated is what I also thought but In his blog Tireman gave a replacement program of replacing the front tires every year for three years and putting the "old" tires on the rear wheels one side at a time. Hopefully he will comment on this.

Roland

[wolfe10]

VERY unlikely that there will be much change in diameter between new and one year old tires. Or between one and two year old tires. Sure, if you drive over 50,000 miles a year, please disregard this statement.

So, "everyone is correct"-- you do not want ANY difference in diameter on one side of a dual or the "taller" tire will carry a disproportionate share of the weight. And you do not want a significant difference between sides on the rear axle. Again, I don't see same make and series of tires only one year apart in age to be an issue.

[manholt]

LOL. After all that, I will do as I always have and that is to bite the bullet every 5-6 years...replace them all!

I do understand that my way, is not for everyone and the rolling change makes a lot of sense.

Carl

[tireman9]

Well I guess I steped in it now.

I suppose it could be argued that there is no way to provide information that will not cause confusion because no everyone has identical rigs. It would be nice to ask people to use my and other suggestions as guides and not as absolutes.

The logic behind my three year rolling change was two-fold. One to lower the sticker shock many were complaining about when confronted with buying 6 tires at one time. In some case I think this probably resulted in a few waiting another year or two before getting new tires. Not always a good idea. The 2nd thought behind the rolling change was to keep newer tires on the front when possible.

Now to the specific observations. The start of the rolling change at 7 years would result in tires being changed at 7,8 & 9 years. It may be better to start the change sooner on your first set of replacement tires. If you keep your RV long enough to need to consider a change of the 2nd set that would mean you have a 12 to 16 year old RV. At that point there are a lot of other things that need replacement so tire expense is just one part of the costs.

Lets look at the size difference between opposite sides of the rear axle. The difference between the fronts and rears on the first year of change would be minimal asa both have 5 to 7 years use on them depending on when you start the rolling change. I haven't measured annual tread wear but this will vary depending on miles, tires used and driving style.

On the 2nd year of course we would have 1 year old tires on one side of the rear and 7 year olf tires on the other. The big question is how much tread has been worn off. I would think that for the majority of tires there might be about 0.10" worn off the new tires and maybe .30" worn off the old tires. This is a 0.20" difference on the radius or 0.62" on the circumference of a tire with a circumference of over 100".

It is important to remember that tires wear fastest in early life and slower as time goes buy so you can't do straight line estimates for tread wear.

So we are looking at less than a 1% difference. Maybe someone could check my assumptions and math and also address if a 1% side to side difference is meaningful in a differencial.

[manholt]

Roger. Just out of curiosity, what kind off rig do you have?

Carl

[tireman9]

I have a 23' Class-C with LT 225/75R16 LR-E tires

A comment on the topic of rolling change and moving the two fronts to one side of the drive axle:

While it is well established in the industry that tires that are a dual pair need to matched in OC to be within 3/4" of each other and that it is many times a good idea to replace the mate of a tire that suffered a road failure, I have never seen anyone suggesting that if one tire on a rear axle that has duals on it fails, then all four tires need to be replaced or at least matched in OC.

If anyone is aware of such information I would appreciate it if the link could be provided so I can correct my thinking.

I may act like I know it all but I am certain there are things I don't know. That's why I keep Brett around

[manholt]

Roger, why I asked what your driving, is in line with what I'm thinking...a lighter coach with LT tires, would probably have a longer tire life, than a 36 to 45 DP.

Is that a reasonable thought?

Or am I wandering alone in the woods again?!

Carl

[tireman9]

Roger, why I asked what your driving, is in line with what I'm thinking...a lighter coach with LT tires, would probably have a longer tire life, than a 36 to 45 DP.

Is that a reasonable thought?

Or am I wandering alone in the woods again?!

Carl

I think the reality is that the 19.5 & 22.5 "TBR" (Truck-Bus radials) are designed for nominal 100,000 mile life and one or more retreads while LT type tires for more like 40 - 60k miles and no retread. I would expect the "life" of a "TBR" to be greater as long as both tires were run with similar load margin (15% to 20%) of max.

[moremiles]

QUOTE TIREMAN9

BUT when I dismounted the tires to remove the original internal TPM sensors, I discovered that one tire from a dual position had severely stress cracks at the edge of the tread & sidewall so it had to be scrapped. The cause for the cracks was a slow leak last winter in it's mate resulted in it's mate to carry excess load, I believe that if I had used the RV I would have have discovered the low tire, fixed the problem (leaking valve core) and it's mate would never have been overloaded.

- - -

This caught my attention. I suspect most RVers don't worry much about one dually going low during the storage season. Just bring it back up and head on out for the summer. The key word of course is "significant" But in the future I'll be much more concerned about any slow leak when I'm not on the road for a while.

[kaypsmith]

To corroborate Tiremans analogies, here is an article well worth reading.

http://www.truckinginfo.com/article/story/2010/01/mismatched-duals.aspx

[manholt]

Kay.

Excellent article! Explanation makes sense. Also makes me wonder why, as Michelin suggests, we don't run extra wide singles? Would solve a lot of problems and make life in RV simpler!

That's all I see on buses and trucks in Norway every year! No dually.

Carl

[tireman9]

Kay.

Excellent article! Explanation makes sense. Also makes me wonder why, as Michelin suggests, we don't run extra wide singles? Would solve a lot of problems and make life in RV simpler!

That's all I see on buses and trucks in Norway every year! No dually.

Carl

Well if you were driving say 80 to 100k miles a year and wearing tires out it might make sense BUT if you get a flat you may end up needing a special tow off the Interstate as you might need to wait a couple of days to get a replacement. The cost of change over is prohibitive and the cost of replacement before you wear the tire out could raise your expenses too.

Since RVs are not carrying load for $$ based on maximizing load capacity the weight savings and fuel economy improvement isn't there for normal RV use.

[dhgoins]

I just bought 2006 Monaco Windsor with 14000 miles and everything looks like new including the tires, no visual wear what so ever, heavy tread etc. I have just about spent out and embarking on a 4 week trip across the south leaving from NC to AZ and back but after reading everything I'm getting nervous concerning my tires, should I replace or not, welcome all suggestions

[hermanmullins]

dhgoins,

If it hasn't been said before welcome to the Forum.

Check the mfg. dates on the side walls. Example, (09 12) means the tires were built in 9th week of 2012. Tires 5 to 7 years old are questionable. Also when inspecting the tires look between the treads. If you have no cracking on the side walls and between the treads you should be ok.

Good luck and have a safe trip.

Herman

[huffypuff]

dhgoins, With only 14,000 miles on it it might still have the original tires on it. If so I would get rid of them as it is a safety hazard to you and others on the road. Congrad on your new to you coach.

[wayne77590]

As Herman suggested. The DOT code is a string of numbers with the last for indicating the week and year. Example DOT code ending in 0712 (last four digits) would be 7th week of 2012.

Welcome aboard.

[tireman9]

I just bought 2006 Monaco Windsor with 14000 miles and everything looks like new including the tires, no visual wear what so ever, heavy tread etc. I have just about spent out and embarking on a 4 week trip across the south leaving from NC to AZ and back but after reading everything I'm getting nervous concerning my tires, should I replace or not, welcome all suggestions

Well if the DOT serial date confirms the tires were made in 2005 / 2006 your tires are 10 years old which means you really should replace them. With luck you can find a tire dealer that has local truck customers (dump, trash, construction etc) that might generate $50 or so per tire.

I would NOT sell them to anyone that would use them for general highway use.