Class A Motorhome Stability

[DLane]

I recently returned from my maiden (2 month) trip to Florida in our new 39' 2007 Newmar Ventanna DP (we are the first owners). The coach was great, but there were times when keeping it in its lane required my full concentration. In complete calm winds and no truck traffic the coach tracks down the road quite well, but when there is any wind (especially when variable in speed) and when some large trucks pass, the coach has a tendancy to wander from side to side. In addition, the coach seems to bounce up and down and rock side to side quite a bit when going over certain road bumps or depressions, yet it can be harsh on some bumps.

I have weighed the coach and set tire pressure accordingly, I have had the chassis checked and bolts torqed where called for, I have had the alignment checked (especially caster) and ride heights checked and all were set properly. So, after reading a good article in the May issue of Motorhome Magazine about shock absorbers and their affect on ride quality and coach stability on the road, I talked to Spartan and have made an appointment to have the suspension (including the shocks) checked out under warranty at an authorized service center.

The coach supposedly has Bilstein shocks, which were one of the top shocks in the MHM review mentioned above. However, my shocks don't look like the ones used in the MH review. I suspect any shock manufacturer makes more than one model of shock so it is possible the the ones MHM tested are different than mine.

I have been considering adding a steering stabilizer like SteerSafe to the front end, but have to decide whether to have it installed when I have the coach in for the warranty check of the suspension.
Everyone I have talked to indicates that SteerSafe makes a noticable difference in coach tracking/stability. Part of my dilemma is that the Camping World where I am taking the coach is around 40 miles away and it will take a week or two for Camping World to get the SteerSafe after ordering it (they don't stock the model I need). So, if I don't have it ordered in advance and installed when I have the coach in for the warranty checkup, I will have to return a second time.

So how can any of you help? You can provide your thoughts on the shocks and road stability issues in general as well as on various steering stabilizers for diesel pushers. My coach has a solid front axle and doesn't have a front anti-sway bar. I believe there are several sway bar alternatives, but they may be more costly than other options and I obviously want to keep the cost down. BTW, one thing I like about the SteerSafe is that it has the added benefit of keeeping the coach going straight ahead even if a front tire blows.
Thanks for any thoughts you provide.

[beaverjim]

dlane, have you looked into a blue ox tru center system? its quite a step up from other steering stabilizer systems. you have the ability to change your center as you drive for varying conditions also if you your concern is to keep tracking strait in the event if tire failure the tru center system has much more centering pressure than other fixed systems. we have had the howard system on mh since new and love it! unfortunatly they are no longer in business so the next option would be the tru center system. jim

[Gary RVRoamer]

I personally don't recommend the Steer Safe or Safe-T-Plus stabilizers - I think you are going to be disappointed. But if you want one, why not order ti from CW for home delivery and then make an install appointment when you have it in hand?

Part of your problem is expectation. You are driving a large vehicle with a lot of "sail" area and winds are going to push on it some. It also has a high center of gravity and a lot of weight, so it is not going to handle like a sports car or even a nimble sedan. Relax, look well down the road instead of right in front and steer majestically rather than abruptly.

Different shocks might take some of the bounce out, but a pro would have to drive it to tell you for sure. Generally, if the coach bounces once and steadies right out, the shock has done its job. Nothing is going to eliminate the first bounce on a pothole or RR track.

For pitch and roll a stronger antisway bar might help.

[Bob (WA0MQE)]

You mentioned you weighed the coach, did you weigh each wheel individually and adjust the tire pressures accordingly? If not, maybe you are overweight on one or more corners enough to cause some problems.

[Rocket Heart]

You have a great coach and if this is your first trip you may be doing the same thing most of us new owners have a tendency to do - over steer. Try driving with just your hands - not your arms - it is supposed to make you not over-correct. If it were me I'd give yourself some time.

[GaryKD]

Hi DLane,
If your coach has Comfort Drive, do not install a steering stabilizer. It will defeat what Comfort Drive is doing for you.

Let's separate the problem you described from the view this is a steering problem.

From the OP, my conclusion is the steering is fine (no wandering). The problem is the coach being pushed sideways or following uneven pavement undulations.
My coach did the same thing, to a level I was not comfortable with. My coach is pre-Comfort Drive so I did install a steering stabilizer (the Cadillac of stabilizers, the Howard Precision Steering System). It helped some, but not enough for me. My assumption is your coach has a track bar, installed from the factory. Check it out to be sure.

The bottom line is the two items that helped to almost eliminate the problem are:

1. an anti sway bar in the rear. CW sells one by Roadmaster. This is the old IPD company. Consider this for your coach.

2. Motion Control Units (air bag restrictors). They can be purchased from Super Steer at http://supersteersuperstop.com/uncat...ontrol-unit-2/

Both of the above mentioned items almost eliminated the problem mentioned in your OP. The bottom line is I finally figured out that when the coach body is pushed in any direction the steering will try to follow the weight shift. That's a lot of weight and mass moving in a direction other than straight ahead. If one can stop/reduce the weight shift, the coach will track straight and require less driver input.

Once these products were installed, I became a happy camper with my coach's performance when moving on down the road.

[two gone rvn]

Gary, how much were the supersteers? thanks
George

[RVDude]

Sounds like more time behind the wheel might be what is needed.

In 2007 Comfort Steer was only in MA and EX I think.

Adding after-market stuff and then going to Spartan will get you legitimate finger pointing. It won't be clear what is doing what to what effect. Keep it stock, keep it all in the Spartan family when you go to Spartan. Then go play.

HWH now makes an active air suspension system that might be what you are looking for. Tracking seems not be the concern, it's stability from that rolling sail.
HWH Active Air Suspension Control Systems

["007"]

George, give this a try should get you a answer.
Welcome to irv2.

[GaryKD]

Hi George,
Welcome to iRV2. The Super Steer Motion Control units for my coach were about $775. I needed adapters for the rear bags. That increased the price a bit. For pictures, go to http://www.irv2.com/photopost/showphoto.php?photo=10503 The photo shows the left rear. The adapters are on each end of the restrictors. The photos to the left and right of this photo show a different angle of the right and left restrictors. I do not have photos of the front (forgot to take them). They are smaller than the rear restrictors.

[GaryKD]

To comment on RVDude's post. He is correct in that one should allow the manufacturer to "make it right" first. I spent a considerable amount of time and $s to try this route. In my situation all I got was everything was within specs. This is when I took charge and began adding the after market devices. I added them one at a time and put some miles on them before deciding if anything else would be necessary. The bottom line is that after over $10K of total expense, I now have a coach that handles great in all kinds of driving conditions. I am very comfortable with the coach.

Editorial:
My coach had a wandering and weight shift problem. When Spartan techs drive my coach they can not believe how well it rides and behaves. This is especially true on the two lane roads they use to test drive coaches in the Charlotte area. I always turn off the Howard system and let them drive the coach. Then I turn on the Howard system and have them take the same route. They now know why I was dissatisfied with the coach as it was delivered. Unfortunately, they remain steadfast in that the chassis is within specs.

[smlranger]

If you decide you want to install a steering stablizer, I also vote for the Blue Ox Tru Center. It is a wonderful device. Also, the Supersteer Motion Contol Valves work very well and is probably the best modification to my Freightliner I have made.

[wcombs34]

I just replaced the Shocks on my 02 Bounder it only has 30K on it. Wow what a difference it made. The ones that were on it was junk I put the Bilstein on no more rolling and bottom out. I do have steer safe installed no wondering tracks good.

[azloafer]

My dealer recommends SteerSafe and Koni Schocks. He says Bilstein Shocks are a little too stiff. I have an appointment to get them put on ASAP.