Has anyone on the Forum investigated converting to the "super single" wheels and tires in place of the duals? I will soon be in the market for a new set of tires all around and thought I may check into this alternative. I understand they reduce un-sprung weight (as well as overall weight) and reduce rolling resistance. Both seem like good ideas. I have been noticing them more and more on semitrailer rigs but have not had the opportunity to talk with anyone who has experience with them.
I have never noticed them on a motor home but do not know if this because there are special issues with RV's or simply because they are a fairly new development.
Any thoughts or experience?
Here's one reasonably recent thread
Any One Using Michelin X One Tires to replace duals? (http://www.foreforums.com/index.php?topic=11889.0)
Here are a couple of older ones
Super Single Tires (http://www.foreforums.com/index.php?topic=6896.0)
Super wide single rear tire (http://www.foreforums.com/index.php?topic=6898.0)
Michelle
They are not exactly a new development. My first experience with then was in the early 1980s where we were running them on 102" 53 foot long trailers down in Florida. Most everyone I knew hated them. We ran across Florida Route 60 a lot between Vero Beach and Tampa. If you dropped one side off the pavement, you had to get the rest of the rig on the other side of the road for well over a mile to get back on the pavement. The petroleum transportation company I drove for when I retired in 2003 also ran them on both the tractors and the trailers. Again, most of the drivers hated them. Poor handling and poor traction were the biggest complaints. Company beancounters like them because they save money, but at the expense of safety. And if you blow one out, you could have to sit waiting a very long time for a new one be delivered. And don't forget that you will need new rims if you do buy them.
I've a good friend with a '96 SOB which came with super singles because of the "All Steer" Oshkosh chassis. He has well over 160k miles and has been full time in the rig for over ten years. He has not complained about handling (a four air bag suspension). He has complained about the cost and availability of the SS tires. He loves that coach; and the all wheel steering is very trick.
These SS tires might be bad this and that , but on the interstate i've been seeing more and more of them .There must be something good about them or these big trucking firms wouldn't spend the extra bucks for them .I spoke to a driver who has never driven a truck with duals .He says they are fine , never had a problem , no blow outs or even a flat , but he has only been driving 24 years .Still don't think i want them on my Foretravel rear just yet . How ever things and minds do change over time , so we'll see . Brad Metzger
On 2 March, Jan & Richard asked, "Has anyone on the Forum investigated converting to the "super single" wheels and tires in place of the duals?" Since no one has said they have switched, might I assume that the general consensus is that we're better off sticking with the factory design of dual rear wheels?
I know from my own personal experience that there is no way I'd go with them. I do know that there are others (members of other forums) that have switched to them. But after they switch, you never hear anything about their experience.
Having to buy new wheels is a big cost obstacle to the switch.
Sort of like having a twin engine airplane. Two tires back there give me a lot more confidence than one. Imagine trying to change a giant single alone and how easy would it be to find a replacement without waiting several days?
Pierce
The singles weigh less than duels and trucking companies warrant the use by being able to scale more payload. I own diesel trucks but choose to manage weight issues in other area's ie all aluminum trailers..Like Pat mentioned, I can't imagine trying to get a rig back on the pavement if you were to drop off the edge of the shoulder... with duals you obviously have the other dual to hold the weight of the rig until you can correct the misstep. Don't know about improved ride, but with trucks and rv's with air ride suspension, all mine ride good as they are. I agree with Pierce with the twin engine airplane comparison... sometimes more is better.. Anytime we have choices, one just has to go with what feels best to them.
One thought is if you have a flat, with duals one tire is usually affected and the other stays up to get you safely off the road and maybe to a tire shop...but with super singles your down for the count and possible would ruin the rim if you traveled very far.
The other thought would be rotation, with super singles they would be dedicated to the rear vs front to rear rotation.
Today I phoned the Goodyear tire store that does truck type tires only . Ask about the super singles ,got an ear full . seems like it is a love / hate thing .Sizes go to 445-22.5 and 20 ply . The guy said the new /younger drivers love them and the old guys hate them and not much in between . He also said that sales are picking up alot over just last year . The new IH Foretravel has 365s on the front and 315s on the back end .My Phenix has 315s all around . Things and times change . Some things take time to settle in . I still don't want them on my coach . Brad Metzger
Kerry brings up a question that has been in the back of my mind for some time. I've never owned a vehicle with duals, nor have I been responsible for the maintenance for one, so this may be a strange question to those of you who have the experience. Are the wheels for duals different than the wheels for a single? In other words, assuming that the tires themselves are all alike all around the coach, can I carry one mounted spare tire (like my car) and use it in any position long enough to get to a repair place? If not, do you carry two spares or no spare? Either way, I'm assuming that a call for road service would be in order. Those wheels and tires look like they are very heavy (and therefore too much like work).
Well here is two cents more!
I have a good friend that owns a trucking firm and runs 140 plus rigs. He also is an RVer, we were talking and I asked what he thought about the SS. His firm some years back purchased 6 new Volvo's outfitted 3 with the SS's and then tracked there performances.
The outcome was that the SS's did seem to average 1-3 MPG better but in the maintenance area the tractors with the SS had more cost due to rear bearing problems and repairs.
All in all after 500,000 miles or so the tractors with SS's were refitted with regular tires and the SS wheels were sold!
All this being said that was on tractor trucks not RV's, and this is just another opinion!
Barry & Donna
David, Unless a PO has changed something the wheels are all interchangeable. on mine I have 6 Alcoa aluminum , some have 4 Alcoa with inner duals of steel. Some folks carry a spare. I don't. Physically I could not change a tire if I had to. Some folks carry just a tire as the low profile tires most of us use ( 275/80 ) is not available everywhere.
FWIW, I have never had a flat on a 22.5 wheel, had plenty on 19.5's though )
Gary B
Well I do not get it, why are the comparisons to truck SS setups, while I have never seen a bus with the SS setup. Lets get a little closer to what we have, think bus for example, when and where did you see the last Greyhound or charter bus running the SS setup? and what was the reaction of the driver to it ?
Seems that would be a tad closer to what we as coach users would be interested in, not some slow over weight poor handling bulky company truck. Our coaches have very little in common with a truck, handling, ride or power.
FWIW
Dave M
David,
The front wheels are different from the back, and usually the insides are different from the outside rears. The few owners I know that carry spare tires carry them unmounted for that reason.
I got on the bus nuts web forum, the general opinion for bus/coach, Prevost offers the SS on their largest chassis, one guy got one, hated it, so changed over to the duals, claims the handling was extreme bad with the ss setup. Also says to stay clear of the 365 tires unless you are very heavy on front axle as they tend to float.
Big tires are not always the answer, the tire size for what the coach was designed for works best
FWIW
Dave M
Just another thought. Any conversion from duel rear wheels to SS may require some additional changes. SS tires run about 10 percent greater circumference as they are a bit taller. That can affect ride height and level setting. It will alter your speedometer. The rear brakes may be another issue. The SOB with the SS has drum brakes in the rear. Some roads which have heavy truck traffic can have wear patterns or grooves in the pavement. The SS tires tend to "hunt" on either side of the grooves and this can be a handling issue. The outboard airbag mounts on Foretravels leave little room for larger tires. Checking that the SS tire when mounted still clears the air bag mount is essential.
We just got back from visiting family in Lincoln, NE, about 350 miles from here. I didn't count them, but I paid attention to the semis that we saw. I saw only one that had super singles on both the truck and trailer. Several had them on the trailer, but the vast majority were traditional tandem duals on both truck and trailer. The ones that had the super singles did appear to be pretty new trailers, although I had no real way of knowing the age of the trailer (or the truck, for that matter). I was more concerned that those big rigs stayed in their own lanes (one seemed to be having some difficulty with that Saturday).
Good trip, no problems, ate too much. No back to work.
There are many issues concerning the single tire on class 8 trucks, mainly around the wheel bearings, (small end), off set rim settings, the old axle width or now they offer a wider axle to help eliminate the bearing failure issue.
Also read where Freightliner changed their policy, do not offer the single wheel option on their tractors at present.
Everything is subject to change, so keep ears up.
Dave M
I probably should have also said that I didn't see a single MH with them. Of course, I didn't see many coaches out on the road then, either. I guess most people got where they were going long before we left home and stayed there until after we had to be back at work.
Three years until retirement!
Personal experience. We(our family) ran the super wide single from...I think...early 70's in an 18' Class C ford/rebuilt engine, modified trany/ etc. etc. etc., towing a 23.5' Chris Craft stern drive from NY to Fl every year. later a 24.5' Aquasport with 200HP outboard over the same route until 1988.
15 years of white knuckled driving. No problems ...other then heart wear.
I drove and sold a few all wheel steering Oshkosh chassis coaches. Crab steering, super single rears. What fun.
Sold one to a missionary to rural Mexico that thanked me as the coach would do switchbacks on mountain roads.
Bob