By: Bob Gummersall (11/03)
The Motorhome arena is full of new chassis products and there is a real need for serious investigation concerning all these developments. As many of my readers know, in past years I made it a point to go to every motorhome factory to personally investigate all the new products that I intended to write about. I reported the results of my investigations to help educate all of you about the pros and cons of all the products I had studied. Most of you know that my Bride of 46 years and I have downsized from a Monaco Diesel Pusher to a 1976 GMC coach that is 26’ long. This last year, we have refurbished, rebuilt, updated and remodeled this Classic and have been enjoying its use since August. The GMC project will be a subject of another piece since my hands are now free of grease, fiberglass resin, paint, sealant, cuts and bruises. It has been a wonderful experience for me and I want to share it with you all.
Now back to my Chassis subject. Spartan, Freightliner and a new upstart Workhorse have introduced new diesel pusher chassis having lots of new features. The proprietary chassis from Roadmaster, Peak, Foretravel, Newell and Dyno-Max have also had serious development done on them. I would love to go study each one, but that is just not possible at this time. So, I am writing this article, hoping that some younger buck(s), with the requisite technical knowledge, will step forward and do some detailed research for all of us. It could be a combination of people, so as to span the country without tremendous expense. So, you guys out there in cyber space, rise to the challenge and let me know if you are willing to participate. My email is bobg@cmn.net and I would love to hear from you.
Let’s define the parameters that need investigation.
Basic Design: Frame Rail vs. semi-monocoque. It used to be easy to evaluate basic designs but it is not so now. As you know in December 2001, I evaluated a frame rail chassis built by Western RV called the ‘Peak’ that had performance, handling, balance and durability that rivals any semi-monocoque chassis. So you just can’t say that a frame rail design is automatically inferior to a semi-monocoque design. I have had reports of semi-monocoque chassis motorhomes popping or cracking a windshield just driving through a severe driveway on a 45 degree angle or raising their jacks to level the coach. This is a case were there was not enough torsional (twisting) resistance in that specific design or the holes that housed the windshields were not the correct size and shape. I have had reports of overweight coaches with tires, wheels or some other component failures cause by too much weight. More than one manufacturer has had to do a complete tire recall because of overloading. We keep demanding more goodies, i.e. a four slideout design is not unusual today and therefore the weights get higher and the chassis has to compensate. Almost all coaches 40’ or over today have to use a tag axle to compensate for the extra weight. Adding a tag axle to an already designed chassis with ABS causes problems in emergency stops, because the two tag axle tires lock up while all the others modulate. Owners are then faced with the tires on the Tag Axle having a significant flat spot. For lots of years air disk brakes were only found on the most expensive pushers. Some manufacturers stayed with hydraulic boosted brake system to have the advantage of disk brakes. Now lesser expensive coaches sport air disk brakes. How important is that? How important is Independent Front Suspension? Some of the most expensive rigs still have live (solid) axle front suspensions. What about placement of Air Bags and how many are best? The list of questions goes on and on.
Warranty Issues: When a company builds the chassis for their own motorhome, is that better? This is called a proprietary chassis. What about engineering of individual floor plans? Does a company that builds their own chassis have an advantage there? What about getting warranty work done? There has always been and will continue to be a kind of finger pointing between the companies that integrate components into a design and the companies that supply the components. For example, if an owner has a handling problem and suspects the front suspension/axle how is he going to resolve this issue. The suspension/axle manufacturer might say that it is a problem with the way their component was integrated into the total chassis/motorhome. The chassis manufacturer might say that it is a fault in that component. The motorhome manufacturer might say that it is the fault of the chassis manufacturer. The Owner is now left with lots of finger pointing and no resolution.
In my opinion, it is better to buy a product that has the fewest possibilities for this kind of a problem. So a manufacturer of the motorhome that uses a proprietary chassis built by a division of their own company is probably a better bet than one that buys a chassis to put under their coach. This is getting blurred, because chassis manufacturers are providing major components, but not a complete chassis, like the front assembly and the rear assembly, that are integrated by the motorhome manufacturer to make a chassis. Freightliner provides the new Liberty Chassis in two pieces, front assembly and rear assembly, to Fleetwood as major components. Fleetwood places a semi-monocoque frame work to connect the two pieces and they have a Chassis. The two piece delivery is not new, it was used by the now out of business Harney Division of Safari in 1997-1998. It was also used by Country Coach in the early days, when they got chassis from Gillig that they proceeded to cut in two and weld back together with semi-monocoque components. So how do we decide where to put our hard earned cash? We need more information.
NEW CHASSIS CONFIGURATION: Now throw into the mix the Spartan mid-engine chassis and we have one more major variable to evaluate. Many of the transit bus designs over the years have been mid-engine because of weight distribution. With the major weight in the center of the chassis it provided a better weight distribution. The early Detroit Diesel engines were laid on their side to lower the overall profile. Even the early rear engine buses had V shaped transmission/differential configurations to limit the overhang and thus improve the handling and ride of these vehicles. This new mid-engine design raises some service issues, since access to the engine from above required access through the floor of the motorhome. It is advertised to allow for a ‘toy hauler’ design in the rear, but has potential to be a very good handling chassis.
Workhorse has announced that they are using advanced electronics to integrate all the major components of the chassis into a computer network with a central control unit to record performance. This design has the immense potential for owners in that diagnosis of real time problems between major components will be possible. Is this important? Others do some of this networking but none reach the integration done in a Lexus automobile. A simple display on the dash of that vehicle shows vehicle performance, GPS maps and route guidance along with the normal vehicle status information.
In summary, I have raised many questions that need investigation. There is no Consumers Report for motorhome chassis that can afford to do destructive testing of Chassis to get this basic information. Each chassis design is extremely difficult to evaluate on its own merits because there are so many variables. The testing that Manufacturers do is always done to verify design parameters and to protect themselves against legal actions. Some manufacturers do a lot more testing than others. But, we customers don’t have access to this information. Unfortunately there is no one source for owner satisfaction information. Every major manufacturer pays an independent company to do “owner satisfaction” surveys but we don’t get to see that information. So where does that leave us? We need to band together, as Rvers, combine our resources, and get the best data that we can to make good decisions. There are so many questions and so few answers. I hope that some of you readers will step forward and help the rest of us make some sort of sense out of all of these variables. We need to be prepared to run the gauntlet when deciding which product to spend our hard earned dollars on. I have great respect for our readers and I know that there are some of you out there in Cyber Space that are just itching to do this kind of investigation.
Rvers Online would love to hear from you on this subject.