Body sway

[dsaugstad]

I have a 40ft. National motor home and would some info on stopping the body sway when going out drive ways. I am looking for info on Road King shocks as if they would eliminate the sway or if there is some other way to help this problem.

[TerryDix]

Originally Posted by dsaugstad

I have a 40ft. National motor home and would some info on stopping the body sway when going out drive ways. I am looking for info on Road King shocks as if they would eliminate the sway or if there is some other way to help this problem.

Motion control units would probably solve this problem

[johnandcaren]

Probably more than one solution.
Last year our new 39 ft Gulf Stream had bad suspension issues, even though it was new. Now, it is a gas Workhorse chassis with leaf springs and not an air suspension which I assume is significant.

Anyway:

First thing was shock research. I've heard of Road King but don't have information. However, everyone on this forum who used Koni FSD shocks swears by them. Go to the chassis forums and search on Koni and see the results.

They were so much heavier duty than the Bilsteins it was surprising. And the difference was more than I hoped for. We moved from uncomfortable to more relaxed while driving. The sway is still more than it should be, to be corrected with a sway bar next year. But the improvement was sufficient to relax and enjoy the ride. Just got back from Savannah GA to Virginia - 625 miles each way, and no problems.

Good luck.

[Wayne M]

I think your key words here are "going out driveways." I have always had that problem in whatever I was driving. I found out that by slowing down to under 1 mph at least keeps everything in place. I just hate it when i forget that. There is a lot of torque on the frame when the wheels are uneven at the driveway angles at some locations. I can get the front end out at a square angle, but the rear is sometimes impossible to do, so that is when i slow way way down.

[Pusherman]

If it's an air-bag equipped chassis, then the answer is Motion Contol Units by Super Steer. Stops the 'Wal-Mart Wobble'.

When crossing a driveway or other divider, air from the air bags move from one side to the next, enhancing the sway effect. These MCU's are essentially air valves which significantly reduces the air flow between the air bags, stopping the 'wobble'.

[Gary RVRoamer]

I don't think any shock absorber can do much for the pitch & roll you get on a driveway entrance. If it is a leaf spring suspension, adding rear air bags might help stabilize it a bit. If air suspension, the motion control upgrade is said to be excellent for this sort of problem.

[GaryKD]

Hi dsaugstad,
Welcome to iRV2. Does your coach have an air bag suspension? If it does, consider:

1. Supper Steer Motion Control Units - Truck Suspension Parts and SUV Suspension Parts Henderson's used to have a nice educational write-up on these, but I can not longer find it. You'll need to know the size (OD) of the air lines going into the air bags. The size of the line could be different between the front and read bags.

2. Anti sway bar for the front and back. Consider the largest that will fit. I have the road master bar on the rear of my coach. There are several brands to choose from. CW carries the Road Master bar. Go to Roadmaster Inc - Roadmaster Suspension Solutions Anti-Sway Bars - Sway Control - Camping World and read about it.

I have both these products on my coach. They work as advertised and I would make the same purchase again.

[dons2346]

My friend installed Road Kings on his Tradewinds and it made a huge difference. The RK is an excellent shock, much better than the FSD. Also cost a few bucks more.

[Easyrider]

I don't think the shock absorbers will help much with what you are trying to control. Shock absorbers are more for the "shock" experienced going over a bumpy road. To help with the "sway" you are experiencing going out driveways I would try heavy duty antisway bars. Your motorhome will still lean when going over uneven surfaces but the sway bars will limit the amount of "whiplash" you experience with the motorhome rocking side to side as you exit the driveway.

[RVThere]

Second the suggestions for Super Steer MCU's. You can install them yourself in less than an hour and they make a huge difference. I put them in my rig about a year ago and my bro-in-law put them in his rig recently and agrees they make all the difference in the world.

[1ciderdog]

Just before Christmas I installed Koni shocks and the Super Steer Motion Control Units on my motorhome. The overall handling was drastically improved and the Walmart wobble significantly reduced. Rather than roll back and forth it will roll a bit but not continue to roll like it used to. The motion control units were extremely easy to install. You cut an air line push the cut ends of the air line into the ends of the motion control unit and that's it - except for adding a wire tie or two if you want. (The instructions say the cuts must be clean with no ragged edges).

[bdpreece]

The super steer motion controls are what you need although a little on the spendy side. I had an old diesel mechanic tell me that he could do the same thing by taking some solid stock and drilling it out to half the size of the air lines then threading it into the air bags and hooking up the air line. He said all this did was slow the air flow in and out of the bags so naturally it would take longer to dump air. Never got around to trying it before getting rid of my National Tropi Cal.

[1ciderdog]

Brian - I expect your "old diesel mechanic" was correct. I could blow through the motion controls but the front were a different size from the rear. It would probably take a good amount of experimentation to get the right size reduction holes.

[bdpreece]

The guy said to go half the size of the present lines and that he had done many that way with good results. I believe my lines were 1/2 and 3/8 or 3/8 & 1/4 inside diameter I don't remember now.