[Robert]

It’s pretty hard to accept the fact that Prevost builds a coach that doesn’t allow the converters to add the “bells & whistles” and remain way within the weight limits… Prevost knows the converters are adding a/cs in the front and other “stuff” why don’t they build them with that in mind? …. they shouldn’t be unsafe !!

[Archived]

Our coaches are based on a seated coach and its load of 50 people. The passengers are evenly distributed so the axles are sized for that purpose.

The converters know the limits and work hard to stay within them. Part of how they are working to keep conversions within limits is the use of light weight materials such as very expensive granite tiles with a thin granite laminated to a light weight material to reduce weight while having the quality and appearance of a granite floor. A lot of the cabinetry which used to be solid wood is now a foam core laminate with epoxy plugs molded in to provide light weight, but which have the strength to accept screws for the hardware.

We have to accept a great deal of the responsibility for the weight because as buyers we want a lot of battery power so we can use heavy electric loads without the auto-start kicking on and off, we want a lot of holding capacity, we want multiple slides, and then we want space so we can cram “stuff” into the bays and cabinets.

Prior to the X3 with its longer wheel base the steer axle was easier to keep within limits because more of the heavy part of the coach was cantilevered behind the tag and drive axles. Now with the X3 there is much less of the bus overhanging at the rear and that is going to have the effect of pushing more weight over the steer axle. Prevost responded by increasing the steer axle to 19,000 pounds. They are doing their best, but then we who buy the coaches want 4 slides instead of 2 so maybe we negate that increase in axle capacity and make it even more difficult for converters.

If all the weight can be biased towards the drive / tag axles I doubt if we would have excessive weight issues. But to do that we need rear biased space to put in holding tanks, the generator, batteries, and AC units regardless of if they are roof or bay mounted. At some point we are going to see the use of lithium ion batteries, more light weight materials, and possibly interior designs that are easier to produce using light weight materials. But until we as buyers take the weight limits seriously that is not going to happen. I plead guilty because I was astounded by how much crap I had jammed into my previous coach. A lot less went into my current coach (mostly because I didn’t have the space to put it), and fortunately I am at but not over the weight limits.

[needtocamp]

Jon,

That is where the 30′ stacker comes in, plenty of room for all the “stuff”.

Sorry, could not resist the sharp stick.

[Robert]

In the example provided by Zmax, that bus is overloaded by more than a ton, almost all of it resting on the front axle.

If it were only a few pounds, it likely wouldn’t matter much. But this is a substantial amount of weight that cannot help but be detrimental to the life of all the components subjected to it and, in my opinion, should not be ignored.

One of the advantages of owning a less complex, non-slide, late 90’s XLV is that even those who live full time in it will find it difficult to exceed the weight limits by any substantial amount unless they deliberately try to.

Prevost does an excellent job of building the most robust shell that a motorhome can be built around. But even as strong as they are, there are still limitations that must be respected without risking premature failure of critical components.

[Sid]

Robert,

I am not capable of determining if dragging around too much weight is better than having it sitting on the axles. My guess is that neither is a good idea.

But, to Paul’s point I know of some coaches from 20 years ago that had overloading on the steer axle equal to the example in this thread, and while that extra weight affects the ability of the air bags to raise the front, undoubtedly impacts braking, and definitely requires greater tire pressures, I am not aware of any failures reported on any forum of bearings or suspension structure.

Remember the 40 foot early XL coaches did not have the extended rear overhang found on 45 foot XL and XLII conversions so it was pretty easy to overload an axle with only a 14,000 lb rating. Stick the batteries and generator in the front bay, add granite floors, load the open bay with heavy stuff and you can bet those older coaches were well in excess of their steer axle rating, yet the only complaint I can ever recall was those coaches were slow to come up to the driving height.

I’m trying to figure out whether I would rather overload my steer axle or break the welds on my engine cradle. The overloaded steer axle seems preferable to broken engine cradle welds, which in fact is a real problem and has been widely reported.

[Archived]

Jon, I (Geo) in no wanted wanted to minimize the inheirant danger of overloading axles or tires. Merely pointing out that the limits are always on the very safe side and that a factor of 5-7% is nothing to loose sleep over. That difference can be accomadated with tire pressure without exceeding the upper limit of the tire. Air pressure is spring rate. See yawl soon at Pelican. Can’t wait to get at least axle weights on our new coach.

[Archived]

I think we are saying the same thing. Limits are limits and should be observed, but I haven’t heard of any failures as a result. The biggest and most frequent complaint about heavy steer axles is the ability to raise the front end quickly.

[Archived]

We got a lot of our initial info from Kenneth Brewer who experienced a blowout on the front driver’s side which resulted in a lot of body damage to his H. I think it was the drivers side ?! Anyway long story short he replaced his 315s with 365s because of the weight issue on the front of the H series busses.

Hopefully Kenneth will see this and may repost his pictures of the damage. Kenneth was a great help to us with all our questions.

Hope this helps.

Thanks for the kind words, Larry & Diane. If anyone wants the pictures, it will take a day or two for me to find them and re-post

. I would recommend going to the 365s for the steer axle. It solved a few problems for me, but I have to point out our coach is not overweight on any axle. But I also have to point out that the front axle is essentially at limit, and this was determined as soon after purchase as possible, loaded to the gills with full fuel and water tanks, and Gwen’s stuff (you needn’t repeat that). We had Prevost (Houston) do the work (and the repairs to the side of our coach).

The reason I changed was for margin of safety, and the fact that at just about any truck stop I couldn’t get 120 lbs. (max according to Michelin) without a lot of waiting for the compressor to cycle on to get the pressure peaked, if it was even possible to get 120 at the tire. I constructed a booster for about $250, but since going to the 365s I don’t need it. Now it requires only between 100 to 105 psi – much better and easier all around. Gwen says the ride is noticeably improved and I believe her, though I can’t really tell. Steering is better, the minimum turning circle is not. The tires do not seem to be quieter to me either, unless the road is smooth and without joints; there is a ring from them, not unlike a basketball, going over road joints and potholes, that is instantly noticeable and alarming at first.

Keep in mind, however, that the Alcoa rims required are different, and because they are not stud piloted, the wheel nut studs are different (smaller diameter, which is helpful), the rim lightening holes in the wheels are larger, and the work required to drive out the old studs and drive in the new is not particularly welcome. I maintain a full alignment should be performed afterwards, as well.

It has already been pointed out that the issues you have are not totally solved by changing tires. But you do need to upgrade to 365s in any event. This leads to the next and last point I have now; if you blow a tire on the road it is unlikely a replacement for a 365 will be quickly found, even 315s are not particularly plentiful in isolated areas (trust me) and if they are located, may likely not be another Michelin: you will wait by the roadside. 365s mean Michelin so far. So, should you also change the tags out as well? I intend to, and I think in your case you probably have to. Yes, a 315 can be put on the wider rim, but I don’t think it would be a good idea to keep it after the emergency is over.

[Archived]

It is my understanding the 365s were developed by Michelin for Prevost.

If you lose a 365 it can be substitued by a 315 for temporary use. However, the reason the tags are 365 on newer coaches is not due to the axle weight, but to provide a 365 for the steer axle if needed, and the 315 bought on the road will be a temporary substitute for use on the tag. Some members have done that and in a couple of cases they just bought a used 315 for the tag axle so they could limp home and deal with their local Michelin tire store.

In an emergency Prevost will ship a 365 to a roadside service provider, but only in an emergency.

[Bill]

Al,

I did see the video & a couple others.Tks.

My wifes` family owns a moving service with 2 yr old Volvo`s. They have experiened many blowouts on new Michelin & Bridgestones, both truck & trailer. They have run pretty much max air press forever and are real sticklers for safety. With well over a million miles driving they now run nothing but Michelin`s based on experience ! Their front blowout tactic involves geting off the gas, hold the wheel tight, steer straight & keep off the brakes until almost stopped. This i`m sure takes guts !

I appreciate everyones input & can assure all that I`m beginning now to eliminate as much of the problem as possible to get within a reasonably safe tolerance since the converter didn`t. Like others mentioned, even a new coach is no guarantee of safe limits. I hope thru this others will take inventory of their situation too.