air suspension

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Robert D. Grant

Post by Robert D. Grant »

Ann,

I am an "Easterner" but have traveled some {twice) in the Rockies and found out right away that anything over about a 7% grade is to be avoided at all costs (even if you have to drive a great extra distance to get where you are going). Perhaps, due to where you live, you can't avoid these steep declines. If that is the case, you have my sympathy and prayers.

Bob
SteveS

Super Springs

Post by SteveS »

Ann P,

What Super Springs model did you have installed? I see that there are two listed for the E450 chassis.

Also, has anyone tried Airlifts Lock-N-liftss?

http://www.airliftcompany.com/Lock-N-Lift.html


Steve
Ann P

air suspension

Post by Ann P »

My notes from Robert Henderson, when I asked him for a description, says the Super Springs are "leaf spring overloads with rollers on the end" . I don't have a catalog number but you could call or email him.

He emailed me before that he's a distributor for Super Springs, which can be ordered from Hendersons Super Steer sales: 888-898-3281x313. They will sell direct to BF owners and give a 10% discount. Or, they can ship to a dealer and provide tech support. Really best to contact them for more details. My costs were $750.

All I knows is that I just love 'em...
User avatar
whemme
Posts: 2110
Joined: Mon Aug 15, 2005 8:05 pm

Re: air suspension

Post by whemme »

Ann P wrote:I've had the coach weighed at each axle several times, and need 80 psi in the rear, 55 up front . I usually keep the airbags around 60-65 ..
Are you sure you need to run 80 psi in your LT225/75R16 load range E rear dual tires. Because if you do, at 80psi, your tires at that pressure are rated to carry a load of 2470 lbs each for a total rear axle load of 9880 lbs. The Dana 80 rear axle in a E450 chassis is rated to carry a total load of 9450 lbs. So if your running 80 psi in your rear tires based on what weight you determined by scale measurement was actually being carried on your rear axle, you are over loading that Dana 80 rear axle by approximately 430 lbs.

In comparison, my 2002 BF 26' RSB coach on a E450 chassis weighs 9220 on its rear axle axle. It has the same Dana 80 rear axle. Each of my 4 rear tires have to support a weight of 2305 lbs and at that weight the required inflation pressure I use is 73 psi.

Here is a direct link to a tire inflation graph that makes it easy to determine the amount of air pressure required in one of these tire based on the actual weight it is carrying: http://www.bornfreervclub.org/bulletin_ ... gr_106.pdf

What I find puzzling is how you lighter weight 24' RB coach has a rear axle load of approximately 9880 lbs whereas my 2' longer (and should be heavier coach) weighs about 660 lbs less on the rear axle?
Bill Hemme - Spencer, Iowa
E-mail: whemme@earthlink.net
2002 Born Free (Ford E-450 V10) 26' RSB
2016 VW Golf GTI - toad
Ann P

air suspension

Post by Ann P »

Well Bill Hemme Honey..."what I find puzzling" is why you think my 24 RB is on a 350 chassis. :) It's right here at the Rally, on a Ford E-450. My rear GAWR is 9500 and my last "weigh-in" was 8875lbs. Front was just 3,350 lbs., where the GAWR is 5000. The psi recommendations came from the experts at RVSEF and another outfit. I'm just a gal trying to keep her axles underweight and properly inflated. But if I keep eating all this food here, I'll be overweight real soon.
User avatar
whemme
Posts: 2110
Joined: Mon Aug 15, 2005 8:05 pm

Post by whemme »

You are correct, I forgot to notice that your 24' RB coach was a newer 2008 model and on that year and later, the rear axle rating was increased from 9450 to 9500 lbs as you say. My post above did refer to your chassis as being an E450.

Based on your 8875 lb scaled rear axle weight, you certainly don't need to run 80 psi in your rear duals. That weight is more in line with what I would except for a 24' BF coach. It does not hurt that you are inflated to 80 psi except for a harsher than necessary ride. According to the inflation graph I referred to, you could reduce your rear inflation pressures to 70 psi which would be completely safe and within the tires specs and would result in a noticeably softer ride.

I assume that your coach is equipped with Michelin LTX tires. The following is a link to a copy of Michelin's inflation charts for their various sizes of RV tires: http://www.bornfreervclub.org/bulletin_ ... on_199.pdf

Actually, this chart applies to listed size tires no matter who the manufacturer is because these inflation specs are dictated by the DOT for all manufacturers.

If you look on this chart for the size LT225/75/R16 E tire, at an inflation pressure of 70 psi, a pair of rear duals will safely support a weight of 4440 lbs for a total rear axle load of 8880 lbs. That is almost exactly what your rear axle weight is, so if you wanted to, you could safely reduce your rear pressures from 80 psi to 70 psi and improve your ride quality.

You said; The psi recommendations came from the experts at RVSEF and another outfit. I am not sure why these sources would recommend a tire pressure higher than necessary.

Since you are at the Leap'n Lions National Rally, come to George Boley's technical seminar Saturday afternoon to discuss and hear other opinions on this matter.
Bill Hemme - Spencer, Iowa
E-mail: whemme@earthlink.net
2002 Born Free (Ford E-450 V10) 26' RSB
2016 VW Golf GTI - toad
Robert D. Grant

Post by Robert D. Grant »

Ann,

In order to "close the loop" on this topic, it would be interesting to hear if you tried lowering the tire pressure and/or air bag pressure (60 to 65 sounds excessive to me under normal load conditions) and what result this had on ride comfort.

Bob
SteveS

super springs & airlift

Post by SteveS »

Ann,

Were you able to keep the air springs (airlift) when you added the super springs?

Steve
mquade
Posts: 16
Joined: Mon Sep 17, 2007 6:17 pm

Ride Quality on BFT

Post by mquade »

Well, I have to chime in here with our experience. We have a 2008 BFT with a 2008 E450 Ford Chassis. Ed told us we were about the first or second party to pick one up. Previously we had a 2004 27" Coachhouse.

Our Coachhouse bottomed out going over significant bumps such as bridges, etc. Our BFT does not. Stock from the factory, it rode significantly better, meaning no bottoming out. Since then, we added front and rear Sway Bars from Camping World and they have eliminated enough sway that sometimes a Semi Truck comes up upon us and we don't feel it, or only enough to barely know its going by. It's very smooth riding and handling now.

However, we've only had the BFT on roads West of the Mississippi.

Also, our air bags are at about 35psi. If we put them at 50, the ride becomes a bit harsher. Bottom line, hard to believe we could make it any better, maybe incrementally only. Miles
bill crommett

ride

Post by bill crommett »

Miles : how do you get your BFT from Madison to the other side of the Mississippi river ?
mquade
Posts: 16
Joined: Mon Sep 17, 2007 6:17 pm

Ride

Post by mquade »

Sorry, should have explained. We live in Madison, WI. It's a 2 hour dr. SW to the Mississippi River (cross into Iowa), then West from there.
Trisha

Post by Trisha »

I find the ride to be somewhat rough in my 2005 26' RB. I have the Koni's and the anti-sway bars installed. That helped with stability so much I was dumfounded. But that's because I was driving with 50mph side winds for a day. Exhausting. Now semi-trucks can sneak up next to me and I see them in my mirror before I realize they're there, and I don't feel them pass.

I run my airbags at around 45. I run my tires at 80 (rear) because the rear-bath model runs heavy in back, even empty. Not overweight, just darned close to the axle rating, even with empty tanks and very little in the cupboards. Born free admitted it was why they didn't put ceramic/china stools and sinks in the 26' RB, because they had a hard time not becoming too heavy in back.

That's what they told me. Your mileage may vary.

I try to run with the least amount of "stuff" i'm going to need, empty tanks, etc. and then I like to keep the pressure as low as possible. I35 North of the twin cities in MN with give nearly any road anywhere a run for the money for potholes and cracks. That and I35 for about 25 miles near Faribault north of Cabellas. Both northbound and southbound.

Fun days. They said Alaska roads are bad, but I found the roads within a mile of my home in MN to be worse, in many cases. Couldn't really say why. Unallottments, maybe.

I'd love to find a way to eliminate the "bottoming out" rough ride, because my refrig. cooling coils have broken already. So has an LP line, my stove (which I nearly have to disassemble and carry in various cupboards or I can't stand the noise, and seams have separated which caused some spectacular leading from the wheel wells, which cost BF a lot of $ to replace after the Alaska trip.

I'm pretty sure it's not universal, but some of us aren't just whining. Ask George Boley. He was there the day the frig broke.

I truly wish I could make this stuff up. With all the stuff I've done to this rig, I'll never get my investment back...but it's got everythign except the more-ryde. If it helps, do it. If your ride is too rough, don't let anyone tell you it ain't. My teeth rattlin' , door that nearly falls out and lake under the sink are convincing enough, if driving with all that ammonia wasn't (thank goodness the thing snapped on top, not the bottom. Much less ammonia that way). Still hard on the lungs in any case.

I got one of the noisy ones, I guess. And I have weighed it, nearly every time I go out. So it isn't that I'm running my tires too high. I wish I could lower them. But not on this coach.

I still love my BF. Don't get me wrong. I'm just saying....

Oh, and there are some 16% downgrades going into one of those Alaska towns, in the southwest. Starts with an S and I am drawing a "404-file not found" in the brain right now.

Start like the trucks. Low gear (or lower) at the top. Slow. Let the tranny keep you from going too fast, as much as possible. Patience is a virtue. I didn't care much for the "million dollar highway" in Colorado while sleeting. Just saying.

Good luck and smooth sailing folks.
SteveS

My solution to improving handling and clearance

Post by SteveS »

We got a 2008 24 RB demo model this spring. In May we took a trip to northern Colorado (from New Mexico). The trip included highways, state roads and several mountain passes. After this trip I had the following items installed on our RV:

Bilstien Shocks
Safe T Plus Steering control
Roadmaster Suspension Solutions Anti-Sway Bar (rear)

In June we repeated the trip. The change in handling was remarkable. Several times we passed semi's on two lane roads and felt nothing. The driving was much more relaxing. From an engineering point of view it would have been better to add these one at a time to determine the difference each one makes, but I didn't have that much time.

On the trip we did utilize the rear drag rollers more that I would have liked. This week I had the Super Springs added (as suggested by Ann). I gained between 2.5 and 3 inches of clearance in the rear with the airbags at 45 psi.

Can't wait for the next trip!!

Steve
Trisha

Post by Trisha »

The Alaska town is Skagway. I'm almost certain they said it was a 16% grade. Really, other than boat, no other way to get there.

Can't get from the East Coast to the West Coast without mountains. Nearly all the way, but California or the other west coast states would be a problem. Mountains all the way along.

The Sierras in California are far steeper grade than the Rockies (at least on the main highways.) That's why there are so few east-west interstates through there, and Cajon Pass is a nail biter most days with unpredictable cross winds and pretty steep drops.

On places like that, I LOVE my Koni shocks and my IPD (bought by Roadmaster) anti sway bars. Just wouldn't even want to drive that stretch without them again.

There are some places, if you want to go, you just have to deal with mountain passes. Anything you can do to help with handling and stability is worth it for those trips. If you stay on mainly flat land, not so necessary but wind is more of a factor in the midwest/central plains.

I love the rolling hills (mountains?) of the east coast, they are fun. But slope is slope (the old rise/run thing). I'm pretty sure the laws of physics apply the same way given the same conditions no matter where you are.

I'd love to see a set of those shocks.

Gotta go make dinner...
Ann P

Air suspension

Post by Ann P »

Hello folks...I wanted to get back on the Forum but my laptop computer met with an early demise while in Custer,SD, after leaving the Iowa Rally. So I've been using public libraries along the way. Have a time limit, so here's a quickie post: The Super Springs are great, am so thrilled to not be scraping the coach bottom anymore...my bike rack is happy too. Have changed the air springs inflation to 35 now.

I had my first RV tire puncture this week. Found a good tire store in Spearfish ,SD to properly pull off the wheel cover from the dually and patch the inside tire. When I previously had air added in Rapid City at a Wal Mart, the guy dropped the valve stem into the liner on a front tire. He pulled the cover off, and used a rubber mallet to beat it back on...with me yelling, No No! He said he knew all about tires and covers, blah blah. Now I have a big dent on the cover, thanks a lot.

Gotta go. Fun to read the Forum again. Nice meeting you folks in Iowa too, and the BF staff. They installed a new carpet in my coach, and some other things but sadly did not line up the dinette quite right. So now the pantry door bumps it- that's another story. The factory guys and gals seemed very dedicated and competent. Sure wish they weren't so far away ...and it was so hot and humid in Iowa. Colorado gals and dogs aren't used to that!
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