So now I'm confused. Are people talking about removing leafs and substituting air bags to make up the difference in capacity (while giving some adjustability) or are people talking about swapping to a totally linked and bagged setup?
Just running fewer leafs with bags wouldn't be hard to do at all (relatively speaking), but I have to wonder just how much of a difference it would make. If you remove leafs you will lose ride height. To gain this ride height back you would have to add pressure to the air bags equal to the load the removed leafsprings were carrying. You would have the same spring rate essentially and the same ride. I think it would be slightly better, however, bucause you would have reduced friction anyway.
Now if you're talking about fabbing up links and air ride for a bus, have at it. That's where I draw the line. I built the front and rear suspensions under my truck in the garage. I can handle something Toyota sized, but a bus and I would just get too nervous.
I think blocks would be a BAAAADDDDD idea in a bus. You could, however, go the zero-rate add-a-leaf method so popular with the offroad crowd. Basically you need to take one or two of those leafs you removed and lop them off so that they are only as long as your spring perches. Make sure you bolt them back in with the centerpin and tighten the u-bolts back up if they are brand new and have only had the initial torquing. If you've had them for a while and have already retorqued the u-bolts like you should after about 500 miles it's time for a new set of bolts.
if you lost an 1/2 inch of ride heigth a square piece of steel 1/2 thick and a drill press wil do the trick. just take the spring mount with the four wholes for the ubolts as a guide mark whole drill. put spacer in put ubolts through and retorque instant ride heigth adjustment.
What type of 'bounce' does your bus have? Is it like the springs are stiff and the suspension doesn't like to move. Or is the bounce because they are soft and the back-end keeps going up and down after you go over a bump? I'm assuming it's the first but want to make sure we are all thinking of the same type of 'bounce'.
Both of the above methods for raising your bus back up would probably work (although I've never heard of using the u-bolts to center a lift block). Using cut-off leaf springs (or a steel plate) and bolt them in the pack would probably be the safest. Typically lift blocks aren't bolted to the pack, they look like this:
I've seen light-duty trucks with lift blocks from the factory, I haven't seen any on medium duty.
How bad is it over the rear axle? If the ride is pretty good there then there may not be much more you can do for the ride in the back because of how the overhang magnifies even the smallest bumps. I've never ridden in the back of my bus (heck I've never ridden anywhere but in the drivers seat!) but even with my 5000lb Scout in the back I think it can get rough back there. I've had to repair some things back there because of that. I ride a fairly new rear-engine air-ride coach bus to work and the back row (only a couple feet behind the rear axle) on that is more 'lively' then the other areas of the bus.
removing leves and installing spacers is the most cost effective fix, if ride is the priority air ride is the way to go, look for an air suspension at the salvage yard to swap in, or remove all but the 2 main leafs used to locate the axle and maintain pinion angle, add spacers to regain ride height and then add airbags to carry the weight. Firestone industrial online publishes their design and engineering data that you can use to make a system or call the local independant truck parts house and have someone help you choose a bag that will carry the required weight, fit the available space and is a popular,readily available and econemical choice, ie; what bag do they sell the most of, it's probably the cheapest and easiest to find if you ever need a replacement. the bags can be plumbed to an onboard air system with a self leveling valve assy, oryoucould set them up like air shocks and just add air to adjust ride height and load.don't forget a good set of shocks to control the spring action
hey guys im not a bus expert but i know a bit about trucks [similar ] let me toss a few things out there ive learned first hand first the spring carry the weight the shocks control the bounce if the springs are too heavy more bounce but has any one tried making a dual actually 4 shock set up like they do on 4x4s probably easier than fabing whole air bag set up dont get me wrong air bags are better but at what effort and cost they also make adjustable shocks for heavy trucks you have to look for them but they are out the one other thing that goes against all theory and what most will tell you is i know first hand several people who have put gas shocks on there highway tractors and they ride like tanks it doesnt make sense but i know it happens i know i guy who went and bought oil shock and paid again to change them and then we get to unsprung weight how about aluminum wheels if possible wheel stud length type of hubs could be double benefit how about 24.5 aluminum wheels with tall rubber about 7% diference 3 to 4 mph over 22.5 just a thought to help with gearing food for thought
Instead of starting a new thread, I've decided to revive this old one and try to add to it's usefulness.
Anyhow, I would like to remove a leaf spring. My bus is mostly built and won't have much more weight added inside of it. As it is right now, it takes considerable force to flex those rear springs. If I hit a speed bump over 10kph all the loose stuff in the back is airborne. The ride up front is fine, but I can hear things slamming away in the back going down the highway as well. I figure I'll do one and see how it works.. If another is needed I'll be a pro and it should only take a couple hours to remove.
Here are some pictures.. It's very difficult to get a good shot without pulling the wheels off.
Don't worry folks.. That's not ALL rust. The entire underside is also coated in red New Mexican dust. I plan on cutting the u-bolts and replacing them, BTW.
I'm thinking of removing the 2nd or 3rd leaf from the top (whichever one isn't connecting the pack to the frame). Does that make sense, or should I remove one from more in the middle? Any input from suspension gurus is appreciated.