Rough Ride - Suspension Issue?

[DennisM]

We purchased a 2003 Rear Side Bed last August. Last year I had kept the tire pressure at 65 front, 80 rear in keeping with the numbers inside the gas fill door. Needless to say, we had a very rough ride last year.

In a conversation with Kim at the factory on another topic earlier this year, he directed me to the Service Frequently Asked Question #5 on tire pressure. To my chagrin, those numbers are the maximum tire pressures, not the recommended tire pressures.

For our most recent trip to the east coast, I lowered the pressures to 57/72. While the ride did improve, it is still jarring at times when we hit a stretch of rough interstate. I find that we slow down to 60 mph to avoid the bone rattles. I am struck my the fact that I don't see the 16 wheelers slowing down over the same stretches. Nor to I see the 40 foot RV's slow. They keep whizzing past us.

Do we have a suspension problem? Is our tire pressure still too high? I would appreciate hearing from others who have owned both a Born Free on the 450 Ford bed as well as a 40 footer comparing the two rides.

Many thanks

Dennis Belcher

[Mel Wilbur]

Dennis, as for the 18 wheelers some of which are hauling up to 20 tons and many of the drivers are sitting on air suspensions seats they just do not feel the bumps that we do. Also many of the 40' coaches have air bag suspension and some weigh in the 40,000-45,000 pound range with long wheelbases so they also do not feel the bumps. We have had those coaches in the past and there is no way one can compare the difference in ride quality. I guess it would be like comparing a 2007 Cadillac with the ride of a 1959 VW Beetle.

You may want to try adjusting the PSI of you helper air bags. Although all coaches are not the same I have found that our coach rides and handles the best with 40psi in them. Also depending on the mileage you may want to consider changing the shocks. Unfortunately you will never get the ride quality of a 40' air suspension coach but the E-450 chassis can definately be improved with patience and of course dollars.

If you check the weight charts regarding tire pressures you may want to consider more air in your rear tires.

[hrgermany]

I have a 1995 BF 26 RSB wiht low milage.I carry 65# airpressure in the front and 80# airpressure in the rear.I also have air bags in the rear carring 50# airpressure and Billstein shocks.I carry max pressure,because
I am sure the rig is a little overweight,but the ride exceptable.First thing I would do have the front end checked.

Hans Rueckert
1995 BF 26 RSB

[Roger H]

Dennis, I have to second Mel's comments about the tire pressures and load ratings. Here is a link to the Michelin truck tire load and inflation table: http://www.michelintruck.com/michelintr ... tables.jsp

It's good info to have around.

Roger

[DennisM]

Our coach is a 2003 with 30,000 miles on it. Would shocks go bad with this kind of mileage?

Second thought is which is more effective in improving the ride, lowering the tire pressure within the range posted by the factory, or decreasing the pressure in the air shocks?


Thanks

Dennis Belcher

[DennisM]

I have read thru the posts about tire pressure. Quite frankly I find it hard to follow and make common sense of. The answer on the FAQ, however, seems to me to be pretty clear. It says:

What is the proper tire inflation for my unit?

Vehicles manufactured by Dodgen Industries, Inc. are carefully designed and built to insure that the actual Gross Vehicle Weight (GVW) and the Gross Axle Weight (GAW) of completed vehicles are lower than the Gross Vehicle Weight Rating (GVWR) and the Gross Axle Weight Rating (GAWR) established by the chassis manufacturer.

Since the actual vehicle weights are lower than the maximum vehicle and axle ratings established by the chassis manufacturer, the tire pressure standard used by Dodgen Industries, Inc. for completed vehicles is also lower than the maximum tire pressures established by the chassis and tire manufacturers. The following chart depicts the tire pressure standards that are applicable to vehicles manufactured by Dodgen Industries, Inc.:

Standard psi Maximum psi
Ford E-350/450
Front 50 65
Rear 70 80
Chevrolet Kodiak
Front 75 95
Rear 80 95

The owner of a vehicle manufactured by Dodgen Industries, Inc. is responsible for determining the optimal tire pressure to use for their vehicle dependent on the cargo weight and driving conditions under which they operate the vehicle. Overloading or under inflating tires can have negative effects including; rapid tire wear, tire failure, reduced handling capability, and dangerous on-road breakdown. The tire pressure standards cited above were selected as safe and reasonable baselines from which each owner will be able to make adjustment dependent on their particular needs.

These ranges seem pretty clear to me. I want to be sensible and safe, yet I am more concerned about a more comfortable ride than I am longer tire life.

Is the bottom line that the ride will always be bone jarring on rough roads - or is it a correctable condition.

Thanks much

Dennis Belcher[/quote]

[whemme]

Dennis,

To determine the proper tire pressures to run in all of your tires, you really need to weigh each of the four corners of your Born Free coach. Weigh it with full fuel, full fresh water tank, all persons aboard that you normally travel with, all clothes, dishes, tools, and etc aboard.

Then you can refer to a prior posting of mine on this site with the direct link provided below:

http://www.bornfreervclub.org/bulletin_ ... .php?t=394

You then can inflate each of your tires with the exact pressure needed in each position - no more, no less. Any air pressure more than is required just contributes to a rougher ride.

As an example, in my 2002 BF 26' RSB, I run 60 psi in the left front, 55 psi in the right front and 73 psi in both sides rear duals.

[Roger H]

Dennis,

One other thought is that the "bone jarring" is relative. While my Born Free occasionally is harsh over a rough bump, the ride in general is much softer than the ride of the Excursion I just sold. The Excursion was just at 7,000 lb curb weight, and my Born Free just over 10,000. The Excursion was on a 3/4 ton chassis and the Born Free on a heavy one-ton, of course. I think that our coach's ride is signficantly more pleasant than that of the Excursion, and that was one of the reasons we bought it. That said, it IS still a heavy one-ton truck with duals and truck suspension, and a relatively short wheelbase. Although the ride is pleasant, it will never ride like a luxury car.

Roger

[grross]

Roger...review ronpurdum's post of Oct. 14. Ford suspension specialist will explain the springs on a 350/450 were designed for trucks not motorhomes. Schocks and airpressure will help; but not solve the basic problem. Some ambulance conversion companies change the original springs from the standard leafs springs to parabolic springs to solve the harsh ride associated with the rear axle. Good luck with your search for a solution.

[DennisM]

I wanted to finish off this thread concerning a rough ride.
As we started to pack up for our July trip, on a whim I took all four tire gauges that I owned and tested them by measuring the same tank of air. Here are the results: 28 lbs, 22 lbs, 26 lbs, 30 lbs. That's a swing of 36% high to low.

Short form of the answer to the rough ride issue was that I was using the gauge that read 22lbs to measure the pressure in the air shocks. So when I thought I had 55 lbs in the air shocks, I really had more like 75 lbs. It's no surprise that the coach went down the road like a brick!

Resolution was to go to a tire store and check my gauges against theirs. I threw out the low reading gauges and set the front pressure to 52, rear 70 and the air shocks to 40.

Ride definitely improved. Coach still rides like a truck, but it's OK.

Moral is to be careful about your air gauges. Get a good one and check it's calibration.
Thanks for all your responses.

Dennis

[purdum]

I have a 2004 26RSB which also gave a harsh ride to the point of breaking lower cabinets. After playing with various air bag and tire pressures I tried to have Mor-Ryde install a rubber suspension system. To make a long story short, they could not install a full Mor-Ryde system but suggested "Poly Springs and Bilstein Comfort shocks". I had them installed and am very pleased with the ride. Cost was around $1300. I now run with 70 lbs in the rear, 60 in the front and 20 in the air bags. Very smooth ride and 46,000 miles and stiil not much wear on the tires.

[DennisM]

Ron;
Who installed the upgrade to the suspension system for you?

Thanks

Dennis

[purdum]

Mor-Ryde. I had stopped at Mor-Ryde and a "saleman" checked and said he could install the complete rubber Mor-Ryde system. We made an appointment two weeks hence and I returned to PA. Went back to Mor-Ryde for the appointment and was told by the Service Manager that they "COULD NOT" intsall the complete system. After unscrewing me from the ceiling and discussing the ride with "Mike" the service manager, it was found that they install the Poly springs on a vehicle as part of the complete Mor-Ryde system. So I have half of the system but as I said, works very well combined with Bilstein Comfort shocks. Someone on this site awhile back said they had a tank moved and had the whole system installed and were pleased with it. If dealing with Mor-Ryde, talk to the service manager!!!!

[grross]

After reading Ron's 1st posting on this subject I contacted the service mgr at moryde who was most helpful. He quoted me a price to purchase the parabolic springs and install them. Upon returning to PA for the summer I decided to check with a local truck spring co. in allentown. I just returned fron Stengel Bros who installed the springs. Ron was right!! It changed the harsh ride substantially. I went over the worst roads I could find and went as fast as I could. Excellant results and I didn't have to spend the $$ to drive to Indiana. Ron thanks for the suggestion.

[bill crommett]

Dennis: Remember that low inflation of tires produces a softer ride, but it also causes more heat in the tires, and heat is the very basis for tire destruction. My philosophy is that even with a harsh ride on the road, it is still smoother than the ditch or a culvert.