Just got my 75 home and want to get started on the chassis.

It needs springs f/r in a bad way. Found some fronts online for $140.00, havn't looked for the rears yet. Would it be better to have the rear rearched or just replace them? Any recommendations for shock replacement?

Got to do fuel lines and breaks also so this is just the start of my list.

more later

John

quote:

Originally posted by John C.:
It needs springs f/r in a bad way. Found some fronts online for $140.00,

That is a pretty good price if they are the ones that don't need air bags. Be sure to buy the ones that match your loaded front axle weight.

quote:

Haven't looked for the rears yet. Would it be better to have the rear rearched or just replace them?

Both rearching and replacing give you (or the shop) only one chance to get it right. And then things go downhill from there, as the springs sag again.

There are two more ways to correct a sagging rear. Both air bags and helpers are adjustable, which allows for the inevitable sag and any changes in load. I use both Air Lift bags and Hellwig adjustable helpers in the rear. If I were to go with just one, I would use the Hellwig helpers. If you want to use Air Lift bags, contact me for more info before buying.

quote:

Any recommendations for shock replacement?

I am a very happy Bilstein user on a number of vehicles. If yours has a steering stabilizer, replace it with a Bilstein, too. If it doesn't, get the parts to put one on. They make a big difference.

John, If you do a search under "springs" and "Air bags" you will have hours of reading to do on the subject.

I replaced my front springs with Henderson's coil springs that are designed for the weight you have on the front axle. That eliminates the airbags for the front. Henderson's also sells everything else you need, like shocks, rear airbags, steering stabilizers, bell cranks, etc. They are top notch.
Jim

After a small amount of research I think I am going with replacement front springs and a AirLift 5000 set up for the rear.

$140 for the front
$220 for the rear

John

quote:

Originally posted by John C.:
After a small amount of research I think I am going with a AirLift 5000 set up for the rear.

John

I wouldn't advise buying the Air Lift bags unless they will allow a return if it doesn't fit well. It the springs have too much sag, the Air Lift cannot lift enough to prevent the inboard triangular ribs on the lower brackets from rubbing the bags and causing a leak. The ribs can be radiused and polished to mitigate this somewhat.

Pictures later.

There is nothing in their info, but somebody there has a minimum compressed height figure for the bag.

This may not be an issue for you, since your Barth is pretty short and light, but it is something to be aware of going in, so you don't learn about it the hard way.

And if you buy stock replacement springs for the front, you'll also have to buy new air bags. My springs from SuperSteer(Henderson's), cost $375 and I'll never have to worry about air bags being the right pressure or them leaking, and the cost of installing SuperSteer springs is the same for installing stock springs. They also provide a much firmer ride and good road feel compared with the spring/airbag set up.

Bill,

I will keep that in mind and wait for the pics. I saw a 20lb min airpressure figure for some bags, these said min 5lbs.

Jim,

The springs that are there now don't have bags in them now. I will check and see if the ones I am looking at require bags.

thanks for the info

John

If you use Air Lift bags on your rear suspension, there is a potential problem. If your leaf springs are weak, as are most P30 springs, the bags could belly out and lay down on the reinforcing ribs of the lower mount.

I have cut away, radiused and polished the top edges of the offending ribs to prevent contact with the new bags.

If the bags still rub, you will need to replace or rearch the leaf springs or use helper springs.



Here is a picture of the Air Lift lower bag bracket. You can see the radiusing and polishing to the two inboard ribs. This provides a little more clearance to lessen the chance of any bag hangover rubbing on the rib.

Also, the bracket should be tilted so that any bag hangover is equal fore and aft under load and pressure.

As far as the front goes, I'm with Jim on the Henderson springs.

John, since the ones you're replacing didn't have air bags, I would suggest that you do this:
--take your Barth to some place where you can weigh the front and rear axle independently.
--load up your Barth with everything you would normally have when you're traveling, including gas and water.
--when you weigh it, make sure there are people in both the driver's and passengers seats
--also make sure your tires are inflated to the manufacturers reccomendation for the weight you have on the axles

After all this, the front coil springs should be rated to handle the weight of the front axle you determined at the weigh station.
In my case, the front axle weight I normally have is 5060#. The springs I bought from SuperSteer are rated at 5000# to 5300#. SuperSteer has them for all axle weights. In your case, it seems possible that you may have had airbags at one time and someone took them out rather than replace them when they started to leak. If so, you should be able to see the lines to the air bags that were used to put air in them. If they're not there, it is also possible that someone replaced the springs with ones that were not strong enough in the first place.
Either way, just make sure the springs you buy are rated for the weight you put on them
Relative to the rear springs, Bill has given you all of what you need. Again, in my case, I added an extra leaf to keep the air helpers off the plate. Bill likes the Hellwig approach and if I were doing it over again, I would us Hellwig with the air bags. Lots of adjustment possibilities there.
This may all seem a little to much, but without getting your frame level, which the new springs/airbags will help you do, you really can't do the right adjustment on the caster when doing your front end alignment
One final note. Your axles have a "gross axle weight rating". Make sure you are not exceeding that number. No amount of spring/airbag work will cure that. If a GAWR is 5000#, it means 5000#. There might be a little bit of wiggle room but just a little. I've seen coaches with a GAWR of 10000# carrying 13000#. That's a disaster waiting to happen.

Jim,

I found one airline in the front, so at some point it did have bags.

I understand about GVW, I have a place close that I can weigh it and see where it is.

Rite now I have about 1/2" clearance between the rubber bumper and stop, so I am really low.

On the Henderson springs, does the weight on the front change that much? I guess what I am asking is that with no air bags you have no adjustment. Has that been a problem?

One more problem in the mix.

Our plan is to get our coach to the point of where we can use it this fall and into next summer. After that we plan on some major remodel throughout. I can weigh it now and see where it's at, but I imagine that after the remodel things will change. Henderson gives a 500lb range 4400-4900lbs. I would expect this would be where it is after the remodel, but it's only a guess. I need to do something now before we put allot of miles on it because it is sitting so low and I know it bottomed out on the test drive.

In the long run I think the Henderson's would be a better solution, but don't know exactly which ones to get and once I get a set I will have to stay there.

Please let me know your thoughts

thanks
John

The main reason Chevy had the spring/airbag set up was that they sold this chassis to a lot of different motorhome manufacturers and never knew how much weight was going to be put on the front axle. At least that's what I've been told. I don't believe it. But the GAWR is the GAWR. The data tag you posted says, I think, 4880# for the front axle. Again, weigh it first and see what you've got. I doubt that the remodeling will affect the front axle that much. But on a short wheelbase, it might depending on what you might want to do and where it is. But let's say that your current GAWR is 4400#. The SuperSteer springs rated from 4400# to 4900# would do the trick and you won't want to go over 4900# anyway. Before I talked to Air Lift about replacing the front bags, they told me that the most new bags would do would be to raise the front end about 1" and that was a full inflation of 100# and that would be a harsh ride. My point is that air bags don't do much to offset poor springs. I bet that you have the original springs in that puppy. Your 1/2" measurement should be closer to 3". I completely agree--get this suspension fixed before you do any long distance driving.

quote:

Originally posted by John C.:
Rite now I have about 1/2" clearance between the rubber bumper and stop, so I am really low.

You should have 1 3/4 to 2 1/2 inches on a bump stop that hasn't been too beat up. With your situation, your bump stop might be be a little flattened.

My scanner hates me today, so I can't send the factory ride height charts, but I think they are on the Barth CD, which you should buy anyway. It has a wealth of information, and is worth twice the price to any Barth owner.

quote:

On the Henderson springs, does the weight on the front change that much? I guess what I am asking is that with no air bags you have no adjustment. Has that been a problem?

Not for me.

quote:

Originally posted by John C.:
One more problem in the mix.

Our plan is to get our coach to the point of where we can use it this fall and into next summer. After that we plan on some major remodel throughout. I can weigh it now and see where it's at, but I imagine that after the remodel things will change. Henderson gives a 500lb range 4400-4900lbs. I would expect this would be where it is after the remodel, but it's only a guess. I need to do something now before we put allot of miles on it because it is sitting so low and I know it bottomed out on the test drive.

In the long run I think the Henderson's would be a better solution, but don't know exactly which ones to get and once I get a set I will have to stay there.

Four ways to go:

1. Buy air bags and you will be OK until you are ready to buy Henderson springs. When you buy the Hendersons, you will have no use for the bags, but the price you paid allowed you to positively buy the correct Hendersons when the remodeling was done.

2. Buy air bags and you will be OK for ever and ever, (but not as good as with Hendersons.) BTW, air bags do fail.

3. Buy Henderson springs now based on an estimate of what you think the post remodeling weight will be.

4. Continue the way you are. I hate to say it, but more P30s than you realize are like that.


Option 1 (buying air bags now and Hendersons later) is a sure thing, but the most expensive. You decide if it is worth it to you.

Option 2 (using air bags forever) is OK, and the most cost effective of the first three.

Option 3 (buying springs now)is dependant on how well you see the future. Things like how well you estimate the weight change of your remodel job and your battery choices, ammo storage, etc.

Option 4 is the only one I would not recommend. The others all work, and are a choice only you can make.

Bill,

Thanks for breaking it down like that. Kinda the options I had thought about also, but it helps allot to see them in black and white.

Think this will be my plan

1. get it weighed just to see where it's at now.
2. get the hendersons and be done with it.
3. for the back start off with the Hellwig adj springs, then the airbags if that don't work.

Looks like the remodel will happen earlier than we planned. Was in the process of dropping the propane tank so I could clean it up and have it checked for leaks, but broke one of the hanging bolts. The bolts go through the floor and two of them are under the shower.

I knew when I purchased this we where thinking remodel, so now I guess it's going to happen sooner than later. We needed to go through every system anyway.

John