New Bus Ride on the Cheap (new Shocks)

NEW SHOCKS: I just replaced all the shocks on the bus and what a difference. I put KONI 90-2572 Heavy duty bus shocks on the front. @ $144.20 ea. I bought six Monroe HD gas shocks for the rear ( $34.00 ea. from Prevost. Four on drivers and two on the tag. Checked out the front end alignment and did not need much adjustment there. Took a quarter turn tighter on the steering box adjustment. ( be careful here, not ever more than one half turn). WaaaaLaaaa a new bus ride. I wish I had done it sooner, what a difference. The horizontal steering shock was bad and leaking. I will order one and replace it when it comes in. This item is not critical, but prevost says it helps tighten up the steering. The shocks are a little tough to get at. Best to pull off the wheels for access on the back especially the tags and have anti sieze on hand for sliding them on.
Good Luck and Smooth Riding

Harry,
Nothing better than new parts on a bus, and then feeling the difference. I getting ready to pull off my front wheels to change the air bags (oh man here comes another HOW TO:) Would I use the same shocks - maybe Jon could step in here.

Also what is anti sieze and where do I get some.

MM

Mango: Anti sieze can be bought in a can at any auto parts store. The fit on the Monroe shocks sliding over the bolt is tight. Coat the inside and the bolt and have a rubber hammer handy to pound them on with. Use the Koni's or the best you can find on the front. The price for the Monroe's at Prevost was great. Have fun on the bags, did they start leaking?

Harry,
I took Jon's advice and started checking the base of my bags, and found this, the next HOW TO:.

Attachment 479

Mike

Since Mike is pulling the wheels to replace the air bags, if it makes shock replacement easier now might be the time to do it.

BTW, Mike is lucky because the leaks in the air bag base are not easily found.

Jon,

Would the same shocks KONI 90-2572 that Harry used, work on mine?
I think you're right might as well tackle the whole 9 yards at one time.

Thanks

MM

Damnit Mike! Would you please stay the heck out from under your coach. Your driving us crazy finding new stuff to work on. Was one or both bags leaking? Did both sides drop together? I'm still trying to find why my front end goes down after a while. Get back to me when you can. Be sure and order the steering dampner when you order the shocks from Prevost.

Harry,
I live to drive you crazy. Everytime I go under the bus it's like an Easter Egg Hunt.

Only the front drivers side bag was leaking, but am going to replace both front ones. I have the leans, but rear only - figure that out.

I think this may have some affect on the rear.

Attachment 480

Air is leaking out of the little red top above the coil, this manifold is located in the steering bay. It's not much air, but if you pinch the red top w/ your fingers you can hear it. The number 4 from the bottom, which is leaking, feeds the rear Norgren valves. Prevost sells a rebuild kit for $34 part # 641928 for the valve. The top mounted coil cost $29 part #641929 ea.

Attachment 481
Coil piece

Mike

Mike,

I think the question about shocks has to be directed to Prevost. If I were to guess they would be different because of the different front axle weights, but maybe that does not matter.

Mike; I was not able to get Koni for the rears, they look a lot heavier than the OEM from Prevost. The numbers Koni gives as follows:
Koni Front 90-2572 OEM # Front 630236 You need two.
Koni Rear and Tag 90-2573 OEM # 630234 You need six
Prevosts offered Medium Hydraulic (blue) Heavy duty Gas type (yellow) I think they are both Monroe. I did not ask Prevost for front shocks because i had previously purchased KONI and had them on hand. I chose the gas shocks for the rear, they come already bushed. The blue ones require added bushings to be ordered with them.
Jon; They have mickey mouse set up on the steering dampner shock, kinda like an add on for motor homes. When I quized Prevost, they recomend replacing it with one exactly like the leaky one I have to help in the laterial steering.
The front shocks have two complete locations to put them. You could have two sets under there. Prevost mumbled something about maybe there are aplications that need four. I put the one pair back in the original location. I guess if was headed to Alaska I would add the other pair.

KONI : http//proamtdw.com/page15edx4.htm

I should have mentioned previously about the second set of shocks.

In the early to mid nineties when some converters were greatly exceeding the front axle weight limits Prevost made some changes that could be applied to all coaches.

One of the things they did was add a second set of front shocks. The principle behind this was not only to add more resistance to rebound so the heavy front end did not jounce, but also to resist allowing the coach to bottom on the front suspension after hitting a bump.

At about the same time they changed the front airbag size on production coaches, but also offered a retrofit larger airbag called "big Bertha". The larger airbag not only addressed the bottoming issue that was helped by the second set of shocks, but on some of the overweight coaches it was almost impossible to raise the front end, and the larger front bags overcame that problem as well.

I think if you are satisfied with the ride and have not had any trouble with your coach bottoming on the suspension then stay with whatever shock set up is on the coach. If it only has two shocks and you add the second set the ride might become too harsh.