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View Full Version : Over Inflate Tires when storing trailer ?


MikeD
09-14-2003, 10:46 AM
We are getting our trailmanor in about a month, and I've been working on coming up with a set of checklists. While working on my checklist for winterizing and storing the trailer, I came across this Goodyear webpage which gives Storage Information for your tires.

On this page, it says that you should inflate your tires to the "recommended operating pressure plus 25%, ensuring that the rim manufacturer's inflation capacity is not exceeded".

Here is website: http://www.goodyear.com/rv/tirecare/maintenance.html

I haven't seen any other references to over inflating your tires for storage on this site. Has anyone else done this ? Any recommendations ?

thanks, MikeD

RockyMtnRay
09-14-2003, 11:47 AM
I haven't done this but it does make sense for two reasons: (1) it compensates for the loss of pressure that will occur because of lower winter temperatures and possible very slow leakage that many tires have; and (2) it reduces the sidewall bulge above the tire contact point. Reading between the lines in the linked instructions, it is this sidewall bulge that's most susceptible to ozone cracking (which leads to premature tire failure).

However, I note that Goodyear recommends the over pressure technique only if the trailer has to be stored with its weight on the tires. I currently have the front of my trailer setting on the front scissor jacks so the tongue could be folded. I'm thinking of cranking down the rear scissor jacks to raise the rear enough that most, if not all, of its weight will be off the tires. It's on a level concrete garage floor so there shouldn't be any frame twisting if I am careful about cranking down the rear jacks by the same amount. Anyone else doing this?

RockyMtnRay
09-14-2003, 12:10 PM
Update to idea of using rear jacks to remove weight from my TM's tires. Just remembered I have a pair of jack stands that can be adjusted to 3 different heights (using a pin). These stands in conjunction with a 2X4 will be tall enough to raise the rear of the TM about 3 inches...enough (in combination with the front scissor jacks) to mostly (if not completely) remove its weight from its tires. The jack stands, being of exactly the same height, also won't introduce any twist into the trailer's frame.

Larry_Loo
09-16-2003, 08:09 AM
Ray,

I wouldn't recommend using your TM's scissors jack stabilizers or any jacks to elevate the ends of your TM trailer in order to take the weight off the tires. This appears to be false economy because in trying to extend the life of the tires you may be causing damage to your trailer's frame. Engineeringwise, the steel frame of your trailer functions as a beam. Most of the load on it is concentrated near its center and, therefore, the axle and tires are placed closely underneath most of this load. This design relieves the stress on the frame under ordinary static and towing conditions - and allows the framework to endure the additional stresses caused by bumping along on rough roads, or excessive weight that you may have put into the trailer. If you elevate the ends of the trailer with the stabilizers or jacks and raise the tires off the floor, you're now supporting the "beam" only at its ends. The beam or framework then will be subjected to its greatest bending loads, and, may be permanently deformed or fatigued.

The stabilizers are only for "stabilizing" the corners and to reduce the trailer's movement when you walk around inside of it or the wind hits the outer walls. It's probably okay to use the stabilizers temporarily to raise a flat tire off the ground if you don't have a jack to put under the axle. Raising the tires off the ground over a long term, however, might do significant damage to your trailer's framework. :( :(

RockyMtnRay
09-16-2003, 08:54 AM
Well, Larry, I think we first need to move away forever from using the term "stabilizers" when discussing any of the newer TMs (those made with the scissor jacks) such as mine. My manual (2002 edition) no longer has any reference whatsoever to "stabilizers"...they're now solely referred to as "scissor jacks". Furthermore, it clearly states "use the rear scissor jack on the low side to level the trailer side-to-side" (page 12). My trailer has jacks; it does not have stabilizers. The word "stabilizer" (and its associated limitations) is not even part of my TM vocabulary.

It seems to me that Mr. Hulsey (a PhD engineer) (or any other of TrailManor's engineers) do know what they are doing and would not have written that part of the manual (or approved the inclusion of it) if they didn't have complete confidence in the rigidity of the TM's frame to handle loading placed well behind the wheels. Similarly, I seriously doubt they would have approved the use of the swing-away tongue if they didn't have confidence in the use of the front scissor jacks to support the trailer on a long term basis when the tongue jack is raised so the tongue can be swung for storage.

Therefore, I have total confidence in the strength of the TM's frame to remain longitudinally unbowed no matter whether I have it setting on its wheels or setting for 6 months on its rear scissor jacks (which are only about 3 feet behind the axle attachment points anyway). I do recognize that the lateral frame members are not as large (or stiff) as the longitudinal members, so I will attempt as much as possible to use identical height lifts on each side to reduce any torsional forces (particularly since the front of the TM will be sitting on its jacks and not on the tongue).

Your concerns may be valid for your '99 model. I respectfully disagree that they are valid for my 2002 model.

Larry_Loo
09-17-2003, 08:44 PM
Ray, you and I are talking about two different things. My comments were directed at what I consider to be a harmful suggestion to elevate the tires completely off the ground with all the stabilizers (or jacks) while you're now referring to supporting the front of the trailer with the front corners' jacks or leveling the trailer with the jacks. In both of the situations that you describe, the tires (and, therefore, the axle) continue to bear part of the weight of the trailer. I agree that these uses of the jacks will not harm the trailer's frame. What I suggested is that it is harmful to the trailer's frame to elevate the trailer's ends with all the jacks to the point that the weight is taken completely off the tires. This is analogous to removing the center posts of the beams in a building and allowing the end posts to bear the weight of the roof and ceiling loads. In time the ceiling and roof will collapse. Likewise, in time you may damage the trailer's frame.

I appreciate the fact that Bill Hulsey is an engineer who knows what he's doing. As a design engineer myself with extensive past experience in designing structural steelwork: elevated platforms, railroad trestles, steel buildings, etc., I am giving you the kind of advice that all design engineers would agree with. Mr. Hulsey can confirm the wisdom of my advice if you want to ask him. ??? ???

RockyMtnRay
09-17-2003, 09:48 PM
No, Larry, we are talking the same thing...using the rear jacks to support the back end of the trailer for an extended period to totally (or at least mostly) remove the weight of the trailer from the tires. I knew I shouldn't have tossed in that mention of using the front jacks...it just confused my main point.

I remain completely confident that based on TM's clear instructions to use the rear jacks for leveling the trailer, it is perfectly safe to use those jacks on a very long term basis (many months) to support the rear of the trailer during storage. Given the litigious age we live in, if they had meant their instructions to be limited in time (e.g. Don't do this for more than 3 days or your trailer will be permanently bent), I'm sure they would have so stated to preclude legal liability.

But to remove any ambiguity about TM's design limitations vis-a-vis long term use of the rear jacks as support for the rear of the trailer, I will call TM in the next day or so to get the official opinion. My bet is they'll say it's no problem at all but I will report whatever they say to this forum.

Bill
09-18-2003, 08:31 AM
Ray and Larry -

I'm anxious to hear what the factory says, either way. But either way, are we making this more complicated than it has to be? Why not just put your bottle jack (you do have one, right?) under the frame just behind the wheel, lift to the desired height, and put some wood blocks or a jack stand under the frame (not the axle!). Repeat for the other side. If desired, lower the stabilizers - as stabilizers - and you're done. The weight is supported where it was designed to be supported, the weight is off the tires, and it's easy!

Bill

Windbreaker
09-18-2003, 11:01 AM
Reason prevails, Bill, I think you have the most level head of all of us.

Happytrails
09-18-2003, 07:28 PM
I could be wrong, but I thought trailer tires were specifically designed to bear extended "parking" time.....made of different composites, sidewalls, etc.....Than regular tires are...........That's why we buy them for our trailers.....(opps! different topic!).......again, just a thought......

Happytrails.........

Windbreaker
09-18-2003, 07:46 PM
Happy, I too think they are. The problem comes in when they are exposed to the sun. If parked indoors or shaded from the sun should be no problem.

mjlaupp
09-19-2003, 08:14 AM
Happy, I too think they are. The problem comes in when they are exposed to the sun. If parked indoors or shaded from the sun should be no problem.

Indoors is ok if there are no sources of electrical sparking such as from power tools used in the garage. Electrical sparks generate ozone which is just as bad as the ultraviolet from the sun. Fluorescent lights also generate UV light. Overall the damage risk is much less when the TM is stored indoors but there is still the possibility of some damage to the rubber.
MJL

RockyMtnRay
09-19-2003, 10:03 AM
Bill wrote:
I'm anxious to hear what the factory says, either way.

I called Jimmie Davis at TM this morning and asked him if using the rear jacks to take all weight off the tires for long term storage would cause any problems. His response was that there was absolutely no possibility of damaging the trailer itself by doing this. He went on to say that he couldn't say whether or not this might damage the jacks, but as for trailer's frame, there wasn't any reason at all to worry.

My new plan is to place jack stands directly under the retracted rear scissor jacks. Reason: the scissor jacks attach to the frame fore and aft of the lifting point, thus spreading out the lifting load over a much greater area of the frame than would be the case if the jack stands were placed directly under the frame. Also with the jacks retracted and with identical height jack stands, I'm going to come much closer to having equal lifting heights on both sides so lateral torsion forces will be minimized.

MikeD
09-19-2003, 11:10 AM
Happy,

My understanding is that trailer tires are designed to cope with extended parking times, but that extended parking is hard on any tire. The Goodyear site addresses the issue of trailer tire storage specifically, and gives some procedures to minimize what damage does occur.

From this discussion and the info on the Goodyear site, I conclude that the best way to store the trailer is to lift the tires from the floor, reduce the air pressure, and cover the tires - (thanks for calling the factory RockyMtnRay). In my case, I want to open and close it during the winter months (new trailer - I have a lot of projects), and I need to move the trailer in order to open it. So, it appears that over inflating the tires is my best bet.

My only other concern is that the Goodyear site warns against moving the trailer "during extremely cold weather". Temperatures get down to 0o F. here - is that "extremely cold" ?

MikeD

RockyMtnRay
09-20-2003, 08:24 AM
Temperatures get down to 0o F. here - is that "extremely cold" ?


As someone who grew up in Montana (where temps regularly drop down to around -30, sometimes -40)...and who lives in a state where the mountain area temps pretty regularly drop to -30 or lower (Frasier, CO is often the coldest spot in the nation); my sense of these things is that Goodyear probably considers zero as being at the warm end of "extremely cold" and was most likely thinking more along the lines of -20 to -40. I say this because it's been my experience that you have to get down around -20 before tires will retain their flat spots for several minutes of driving.

Personally I wouldn't be moving the trailer around or doing much with it when the temp is much below 10 above...the tires aren't the only parts that get stiff and brittle in cold temperatures.

pemc4279
06-05-2018, 07:11 AM
Ray and Larry--you might need to agree to disagree. After all, the whole purpose of owning and using a TM is to relax and enjoy life! With that said, my contribution may be akin to comparing apples to skateboards, but here goes.

Before the TM, we owned a canvas sided pop-up. I used the scissor jacks/stabilizers to level the trailer and it deformed the door opening. I'm noticing some very minimal tweaking in the door of my TM. As a result, I refuse to level the trailer with the jacks/stabilizers. I use the Anderson leveler (greatest thing in the world for this!) and tongue jack to level side to side and front to back. Then I only firm up corners with jacks/stabilizers.

While you're both referencing professionals, there's no better teacher than experience and my experience tells me the jacks/stabilizers should not be used to level. I understand it's possible I'm being over-cautious, but better safe than sorry!

Happy Trails!

tentcamper
06-07-2018, 01:38 PM
I like the idea of over inflating. I always lose about 10 psi after winter storage.

Maybe I will take some weight off the tires. Never have done it before. But I think using the jacks on the camper might will best for me. Drop the nose down about 6", extend the rear jacks, rise the noseback up to level with the elec jack and drop the front jacks. I should get about 6" lift with almost no effort.

BrucePerens
06-08-2018, 10:31 AM
I will continue to lift my tires off of the ground during storage. I think the biggest problem with leveling the trailer using the stabilizers is that it's pretty easy to push a stabilizer over when it's fully extended. Especially if it's only attached with two bolts. Some of them provide a better bolt pattern.

tentcamper
06-08-2018, 06:11 PM
I would not be to concern with two bolts on each jack.. But I worked under cars for years, up 2 feet on 4 jack stands with no bolts. But I get the visual thought.