How bounce is too much bounce?

[Jason Worman]

Hi everybody,

We are currently enjoying a trip up the Oregon coast and are in St. Helens for a graduation party. Driving up Highway 101 a bit rough. Noticed in spots especially dips and rough patches coach bouncex a bit, is this normal? Also when crossing rough patches of road coach would bang on front and rear end. Does this indicate we need new shocks? Otherwise on straight stretches coach just moves along smoothly. Going home tomorrow down I-5, will be interesting to compare the difference in ride.

Thank you


Jason

[Carl Boger]

Not knowing your coach it is difficult to say what is normal for it.  It does sound like you may have some items that are starting to wear some.  This could be your shocks, tires, airbags, and strut bar bushings assuming it has all of these items.  I don't believe it should be bottoming out front and back over small dips at normal speeds.  Anything rubber under the chassis will wear and should have at sometime been replaced on your coach.  You really need to inspect each piece to see if it is performing as intended.   

[Chuck Jackson]

My coach was porpoising (bouncing) on large dips (I40 east between needles and hwy 95 - the exit for Lake Havasu). I knew that it was the shocks so I replaced the front shocks and the porpoising is gone. I plan to replace the rears now also.

If everything is in good working order, I'd be willing to bet you need shocks but like Carl said, you need to have it inspected to be sure.

[Scott Ramsey]

We ran that same stretch a couple of weeks ago and a little bounce on bumps such as those doesn't seem out of line so long as the coach recovers with out more oscillations.  The banging on the other hand doesn't sound right to me. We have Koni shocks all around and have been happy with them on our 03 Monterey.

[Keith Moffett]

Here is the 10 cent version of my 2 cents.
Yes shocks wear out but since they are so spendy it doesn't hurt to tune up the air system first. 
Make sure frequent bumps and turns are not using more air than your compressor can provide.  I recall on another thread here something was said about a filter on the intake for the compressor being dirty and blocking air flow.  Air leaks or bad air bags can also weaken the air ride.  There are check valves you can put on air bags that limit the air used on each bump.  Gerald can tell you the name I believe.
Our Patriot used to be great on the first couple bumps but Wa hwy 18 would be one long stay in a bouncy house.  That said sometimes shocks are the final word.

[Joel Ashley]

As others here and I’ve previously advised numerous times Jason, I’d definitely call Henderson’s in Grants Pass and see if they can fit you in, although this is their busy time of year.  At least have them do one of their on-highway assessments.  8 new Koni’s installed were around 2 grand in 2015.  That and Henderson’s own little Super Steer Motion Control valve’s all around made a pleasant difference in the up/down and sideways “bounces” we used to get on some roads even when the coach was brand new.

No, this alteration isn’t cheap to do, but to us the difference in road response and wind/passing truck reaction was worth it.  White knuckles... a vague memory afterward.  I had a Safe-T-Plus on our old Pace Arrow in 1985, and after scary reminder videos online and stories here, I had Henderson’s put one on Monty Rae too.  That no doubt also contributes to the handling improvement.  Still, crossing really rough road patches requires a prudent speed adjustment.

https://www.hendersonslineup.com/

Joel

[Jason Worman]

Thank you to everybody. Our rig is the 1991 Contessa built on the Gillig chasis. I pulled out the original manual with different suspension trouble points and without a whole lot of records plan to take the rig in for a complete inspection of the front and rear end. I did notice that while driving air bag pressure seems to stay very consistent at 125-130 psi. I do hear the air deflate/reflate on hills, after dips, rough going and such. Does not loose much air when parked.

Jason