Tire Wear

traveler · 08-11-2012, 08:19 PM

I am considering upgrading to 17.5 tires with the required wheel from Doubletree, but I have a general question first.

I have almost new G614 tires and seem to have a unusual tire wear pattern. The inner and outer edges of the tires on the driver side are wearing a little faster that the same edges on the door side. I assume that this is because the driver side tires are carrying more weight and actually require more than 110 psi cold to properly inflate them. I am a little hesitant to cold pressure them to say 120 psi.

I suppose that the tires (both front and rear driver side) could be misaligned but I tend to think that it is a pressure issue.

I called Double tree and got a tacit agreement with this diagnosis. What do you all think. I suppose the left side of my TK3 might be a few hundred pounds heavier that the street side, but will that cause the tire wear I see?

Stripit · 08-12-2012, 01:17 AM

Do not run them up to 120 cold, max of 110 cold is where you should be. Depending on if your fun time or full time the kitchen side will be a little heavier to a lot heavier. When I was full time we were 1,100 lbs heavier. Two possibilities on the tire wear issue. 1. alignment of the axles is out and needs to be corrected. 2. broken cord or cords in the tire will cause a miss wear issue and could be the beginnings of a tread failure and about to leave the tire casing. This is what causes a lot of damage to the trailer.

traveler · 08-13-2012, 10:06 PM

This answer in interesting. So, loaded to the tire design limit (which would be the case, if the kitchen slide side was about 1000 pounds heavy) this leads to separation of the steel cords and subsequent tread separation??

I have had 3 blowouts on short service G614s (like less then 12,000 miles on the tires). Two on the left and one on the right--but the right one was roatated right from the left. Is it really so simple that the TK3 is so heavy that the G614 is a marginal tire for the trailer??

Another question... are all overloaded tire failures (diagnosed by both inside and outside tire wear) the major contributor to tread separation??

Diesel-Gypsy · 08-14-2012, 08:42 AM

Traveler, I think you have got it 100% correct, the G-614 RST is a marginal tire for the MS.
I too have had blowouts, 3 of them, always maintained proper inflation, kept speeds under 65mph, never over-loaded, still had tread separations.

I think what really must be the root cause is over-loading, but in a dynamic versus static analysis.
We all weigh these units standing still, and we all are usually within the weight permitted, but in a rolling down the road scenario we are all over-loading our tires with every bump & heave, and dip we pass over.
Just go stand on a scale & weigh yourself, then with-out actually jumping, just quickly flex your knees and watch that scale needle bounce 40% higher than your static weight.
After a 10,000 miles of that type of dynamic over-loadeding, the cumulative effect is tires which are damaged, and fail in service.

All the Suites coming out of the factory now are on 17.5" rubber, why...?
So, I too have switched-over to the safer alternative, I am now on "Big Rubber".

Just my $.02

RL

Stripit · 08-14-2012, 09:35 AM

Diesel Gypsy, Excellent answer, and for years the G tire has been having issues. So many of the trailers I weighed had that tire carrying anywhere form about 95% to 110% of its rated capacity sitting still on the scales. Also many folks had less than the max 110psi air in them lowering the capacity. When the G tire was released it was installed on many trailers because at that time the trailers were starting to become heavier and that tire gave the trailer manufacturers a step up for some safety. What happened? the trailer manufacturers started to make the trailers even heavier and to a point overloaded those tires. Now the H rated 4,805lb capacity tires in some cases are getting close to their rated capacity with the loaded trailers they are under. Weighing each tire and axle is so important to understand how you are loaded and what you can do to protect those tires from working so hard. When your working any piece of machinery at close to 100% of its ability, you end up with failures of some type much sooner than if it was running at say 75 or 80%. The G tire is just over worked and will quit at a much sooner rate than the H should given the same set of conditions(weights being carried). The kitchen side in most is heavier, my trailer 1,100lbs heavier when we fulltimed and I peeled the treads off of both the left side G tires within 100 miles of each other doing damage both times. I then moved up to the H tires. And believe me when i say I own the most weighed trailer out there, and neither of those tires were over the 3,750lb limit, close, but not over and never run with less than 110psi, ever. But they were worked to death in less than 3 years.

Diesel-Gypsy · 08-14-2012, 08:44 PM

True enough, and the switch over is straight forward, and easy.

Then:

Good insurance:

One less thing to worry about.

Rick

Motor31 · 08-15-2012, 09:21 AM

Traveler there is another consideration to the tire wear issue. If you have had a tire changed and the jack was placed anywhere but under the spring pad then you probably have a bent axle. The axles that are installed under these units are thin walled steel tubes, just like the frames. They are not heavy enough to jack up anywhere on the tube except for the spring pad and the jack head has to be there and not on the tube itself.

I know from experience that the tire places just shove a heavy duty jack under the axle and crank it up because the folks are used to solid axles and do not know about the hollow tube style we have.

Something else is that the axle is installed with an arch to it. It should have a slight but noticeable arch upwards in the center section. If it is flat, it is bent due to overloading. If you have the older 7,000 lb axles, going to the 17.5 tires will not keep the axle from bending or going out of alignment. The new tires will wear out very quickly and unevenly. The 17.5 tires are also more expensive than the 16's so you will be losing even more money.

billr · 08-16-2012, 07:29 AM

Quote:

Originally Posted by Diesel-Gypsy

True enough, and the switch over is straight forward, and easy.

Then:

Good insurance:

One less thing to worry about.

Rick

Its about time!! :lol: :lol:

**wingnut60** · 08-16-2012, 11:04 AM

" If you have the older 7,000 lb axles, going to the 17.5 tires will not keep the axle from bending or going out of alignment. The new tires will wear out very quickly and unevenly. The 17.5 tires are also more expensive than the 16's so you will be losing even more money."

I respectfully disagree with this statement, unless the trailer has way more than 14k on the axles themselves. I, and several others, have made the changeover to the 17.5" wheels/tires and have not experienced abnormal tire wear. An 18K gross trailer with a 4200lb PW will have 13800 on the axles--close, but not over. I made the change and put over 25000 miles on the XTAs with no problems in tread wear or flats/blowouts.
This last spring, I put the 4k spring paks on in place of the 3.5k paks, and the axles were both: still arched, and in alignment.
Joe

Motor31 · 08-17-2012, 07:47 AM

Wingnut you might have quoted the entire paragraph instead of taking part of it and then posing the quote out of context.

**wingnut60** · 08-17-2012, 10:07 AM

Sorry that you think the quote is out of context, as I feel it isn't.

If you meant that higher capacity tires would not counter axle overloading, you are correct--and no tire can prevent an axle from bending if mistreated/overloaded. However, that is not how I interpreted it. I was trying to get across that simply changing to higher capacity wheels and tires as many have done, is a great way to get away from the early (and later) DRV tendency to equip new units with tires loaded near the max capacity.

I apologize that it came across as a criticism, I just do not agree with what you said. And I did include 'respectfully' when I said it.

Joe

Jack in Alaska · 09-04-2012, 04:04 AM

When my MS was new (2004) it was pulled from Indiana to Wash. state to Texas to Cancun, Mex. to Ind. to Alaska to Wash. The left front tire wore smooth on the outside and the right rear tire wore smooth on the inside.
I replaced those two putting the new ones on the same axle. No more crooked wearing. I have since replaced all 4 tires and they are all wearing straight.
Could there have been a manufacturing problem with those 2 crooked wearing tires.?? Nothing else has been changed.