Handling issues

There is a draw-back to excessive CCC margin. The ride will be exceptionally harsh. Considering it's a house with contents, less harsh is better. There is a delicate balance between quality of ride and excess CCC with no real formula to follow.

Empty is 10,702. max with tow is 19,050. Diff is 8,348. Even if I towed it's max of 5,000 that still leaves 3,348.

If it was a Chevy chassis, empty would be 10,550. max would be 17,550, Diff is 7,050. max towed would be 3,500 so I'd have 3,550 left.

You still have to worry about each axle weight and there's no way I'd have room for even close to that much weight distributed over each axle but it's there. Some I looked at were well under 2,000 pounds left when pulling something. A few people, gas and water can equal almost that.

The plan was find something under 27' with no slides with a 450 chassis then weight and handling should not be an issue. Did not want to be driving something that was at or near it's max capacity all the time.

... additional 8,348 pounds ...

Your coach may have a lot of NCC, but I find that figure hard to believe. Coach's empty weight would have to be around 6,000 pounds. Or am I missing something?

Tire pressure is important but when looking at models for our purchase last year I always compared the base weight with the gross combined weight rating. There were quite a few that after adding the weight of a couple of people, a full tank of fuel, and a tank of water they could barely carry a dozen eggs.

Weight was one of the reasons we decided on no slides and going with the E450 chassis. My 27Q will carry an additional 8,348 pounds of fuel, water, people, toad, and junk. I doubt I will ever come close to that. We tow a trailer with two Harleys and a canoe so thats around 2,000 pounds (towed weight). Still leaves me with over 6,000 pounds for us and everything else.

It's a 2006 (2005 chassis) and I have absolutely no issues with handling at any speed and it's all original equipment.

Looking at some of the longer models I'm sure the wheelbase on many is too short. Some look like you could jump on the rear bed and make the front wheels come off the ground.

Vach wrote:
On the highway it tracked straight as long as there were no bumps, cracks or grooves. Very rough ride. Not teeth rattling but rough. Rocked and rolled around corners. My wife can drive my truck pulling our tailor but don't see her driving something like that.

First, I'm not buying into the idea that manufacturer's have their head up their tail pipes when they specify a chassis. TODAY!!! They choose some thing that will carry the weight and the suspension is designed with that in mind by the chassis manufacturer. Coach builders generally specify a long list of OEM suspension options.

OK.... Let's take a gradual approach. What you are describing... rough transitions over bumps, cracks or grooves and generally a rough ride may relate to the tire pressures. There's an 'old school' herring that assumes that more is better (up to the pressure on the tire's side). That's often not the case. There is a placard on the driver's side door or frame that specifies tire pressures. That pressure is for the FULL RATED GROSS VEHICLE WEIGHT. So, it may be too much pressure for a lightly loaded vehicle. Lowering the pressure by a couple of pounds will soften the ride appreciably because you are getting some side wall flexing in the tire. Now folks are going to jump in here and start talking about low pressures and blow outs. That's only true if the tire is extremely under inflated. What's really going on here is you set the pressure a couple LBs lower than the data plate. (It would helpful to know the actual weight but not so necessary.) As the tire heats up it will increase in pressure about 1 LB / 10 degrees F. The idea is to find just the right pressure to give you a smoother ride while more closely approximating the pressure actually required for the weight of the vehicle.

Next, rocking and rolling around corners. Very typical of a heavy vehicle with a high center of gravity... like most coaches. So, go slowly around corners or through those road situations that cause the rocking and rolling. Before you jack around with all kinds of suspension upgrades, shocks, roll bars, sway bars, etc.. go back to step one above. If the tire pressures are too great for the weight, you lose the compliance and shock absorbing ability in the tire. And, yes! The tire is part of the suspension. If they are a little less stiff, they will begin to absorb and dampen some of the forces earlier that are creating the sway. Sort of like extra shocks... of big rubber airbags, if you will. You will never eliminate it... and you don't want to... but you can reduce the swinging moments by letting the tires do some work.

Just a couple thoughts...

I feel that most handling issues are a result of what the motor home builder has done to the cab and chassis and not because of what the base vehicle builder has done. I don't believe the van builder is putting out a vehicle that as it comes from the factory, can't safely carry the maximum load it was designed for.
The MH builders try to put as much as they can into these rolling houses. Whether they're putting too long a box on too short a wheelbase, or screwing up the weight distribution of all the goodies,the lousy handling is their fault, not the cab builder's.
In my case I've had 3 class Cs. I currently have a 1997 Coachmen E350 24'er and a 2014 Itasca E450 32 1/2'er. They both handle quite well and no changes over stock were needed to get that good ride. My worst riding class C was a 1995 22' Four winds on a Chevrolet cab and chassis. It tracked OK, but it really leaned while taking corners, even when new. I also should mention that the 5.7L engine was barely adequate for that small MH, while the V10s in the other two provide more than enough power.

Vach wrote:
Sorry to sound rather negative, but I just reread some of these posts. It sounds like another way of saying some of what these posts say is that it's common for manufacturers of small motorhomes to sell RV's that are not comfortable, perhaps even safe, to drive without requiring several thousands of dollars of "upgrades". No wonder I'm having a hard time finding something I really like.

I surely understand your feelings over this. I too feel the same about it. I still scratch my head as to why the NTSB continues to allow motor homes on the road without these simple upgrades implemented as a requirement. The chassis manufactures are installing stabilizer bars, shocks and steering dampers already. They are simply insufficient for the application. For example, the four shocks, the steering damper, and front stabilizer bar for an E450 cut-away chassis are the same ones installed on an E250 van. Just install heavy duty parts and all will be greatly improved. It wouldn't cost but a few dollars more to the chassis manufactures.

I think the substandard parts assume the cut-away chassis will be a box truck being driven around most often empty or with a light load. They don't take into account that for RV applications, a fully featured heavy house, people and contents are always on the chassis when being driven. They also don't consider the poor weight distribution from the house, modifications often made to the wheel base, and various rear overhang extentions. Each motor home has it's own characteristics because of that. Because of variations in dimensions, wheel base, and weight distribution, the chassis manufacture could never come up with the "Ideal" chassis. They'd be changing out springs & spacers, shocks and such for each particular RV design and model. But they can surely install some heavy duty suspension parts to positively impact every motor home in handling which translates to a safer rig that stays within the lines, reduced driver fatigue, and will brake in shorter distances. With the wheels firmly planted on the street, braking distance is naturally improved.

There is a simple and affordable means to make motor homes notably safer to drive, but the NTSB, chassis manufactures, and RV manufactures close their eyes to it. It's left up to us which isn't the decision I agree with.

As for us, we did invest in the heavy duty suspension upgrades and it did make all the difference in the world with our particular rig.

Don't give up just yet as I said before keep looking and try to find what you want or like on a Chevy Chassis, you will not have to spend a lot of $$$ on upgrades to make it comfortable to drive or ride in.

Mine rides great and drives great and I haven't spent a cent on the suspension.
Good Luck

Sorry to sound rather negative, but I just reread some of these posts. It sounds like another way of saying some of what these posts say is that it's common for manufacturers of small motorhomes to sell RV's that are not comfortable, perhaps even safe, to drive without requiring several thousands of dollars of "upgrades". No wonder I'm having a hard time finding something I really like.

Vach wrote:
On the highway it tracked straight as long as there were no bumps, cracks or grooves. Very rough ride. Not teeth rattling but rough. Rocked and rolled around corners.

Vach,

You describe a very common scenario across many different brand motor homes. The suspension upgrades we all talk about takes care of everything except the rough ride. There is no easy/low cost cure for a rough ride.