Suspension Improvements - Best Order

[S1njin]

So what is the consensus best order of suspension improvements on a E450 motorhome?

My guess:
Proper tire pressure
Front end alignment
Rear Sway
Front Sway
Shocks
Steering Stabilizer
Rear Track Bar

Am i close?

[OFDPOS]

pnichols wrote:
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OFDPOS wrote:
If those were the OEM shocks, any of the new Bilstein's , Monroe, Koni's shocks would have helped with the slam/pounding.

Scratching my head and thinking about it ... what you say doesn't seem to add up physics-wise.

Most Class C owners think they need the single action heavy duty (which pretty much means "all the time stff") Bilstein, Monroe, or standard Koni shocks for good control. "Good control" usually meaning control of sway, leaning, wind-push swaying, and front-to-back rocking. Stiff shocks is what's needed for these situations.

For the rapid motions resulting from roadway cracks and potholes it seems to make sense that the last thing needed would be shock stiffness added to leaf spring stiffness. If this is true, the high frequency mode of the Koni FSD shocks (not Koni's standard shocks) .... which as I understand results in momentary reduced damping ... is what's needed. In other words "no shock at all" is what's needed on the rapidly occuring ("high frequency motion") edges of cracks and potholes.

Like you I replaced old worn out shocks with new shocks. Like you I noticed an instant change for the good.
You put on the koni's FSD's , I put on the Bilstein's not once but twice on older MH's and noticed the instant change for the better.

Now reading comments like yours a few post up and others, I bought into the koni's FSD's being the mighty best invention since sliced bread.

Boy was I wrong ! The front end dives on every dip in the road what Whizbang seems to be getting confused with swaying.

Here is a blog about porpoising and you can feel good because it talks about the koni's FSD shock. 😉

http://blog.goodsam.com/porpoising-what-it-is-and-how-to-stop-it

Like another post I said the Koni's helped with the slam over the bridge joints and major cracks in the road.
BUT so did the Bilstein's and had I gone with them I'd have close to $300 in my pocket.
The place where I had my alignment done stated how the koni's were designed to work as you described...Rebound BUT I'll take a front end NOT diving down every time I hit a dip in the road over the uneasy feeling of the knoi's .. They sell both the Bilstein's and Koni's But I think they were a little bias, the co-owner was wearing a jacket with a koni patch on it... lol

I'll leave the koni's on the rear, but I see in the near future swapping the konis FSD's out for Bilstein's in the front..

[pnichols]

javascript:;

OFDPOS wrote:
If those were the OEM shocks, any of the new Bilstein's , Monroe, Koni's shocks would have helped with the slam/pounding.

Scratching my head and thinking about it ... what you say doesn't seem to add up physics-wise.

Most Class C owners think they need the single action heavy duty (which pretty much means "all the time stff") Bilstein, Monroe, or standard Koni shocks for good control. "Good control" usually meaning control of sway, leaning, wind-push swaying, and front-to-back rocking. Stiff shocks is what's needed for these situations.

For the rapid motions resulting from roadway cracks and potholes it seems to make sense that the last thing needed would be shock stiffness added to leaf spring stiffness. If this is true, the high frequency mode of the Koni FSD shocks (not Koni's standard shocks) .... which as I understand results in momentary reduced damping ... is what's needed. In other words "no shock at all" is what's needed on the rapidly occuring ("high frequency motion") edges of cracks and potholes.

[ron_dittmer]

whizbang,

I side with everyone else, kindly and respectfully disagreeing with you. The floatie-boatie handling that resembles a drunken sailor is a dangerous driving condition. It is a poor decision to prioritize a softer ride over stability and control.

I would not be typing here right now if not for the handling improvements I had done with our rig. Me and my wife would instead be dead. We almost lost our lives on a winding canyon byway during a hard brake-slamming situation done while in a sharp turn at a misjudged speed that was way too fast. The suspension improvements kept all 4 corners firmly planted on the pavement for the brakes and tires to do their job. If I was setup as you, our motor home and tow vehicle and us inside, would have tumbled hundreds of feet down into the canyon.

You will never convince me otherwise because I drove our rig both ways, before and after the suspension upgrades. Done right, the porpoising issue is less than you make it out to be. A rig unmodified does porpoise too, but is masked by all the other movements. Better to go a little up/down rather than swaying and wandering about all over the road along with a little up/down. Not just for all the reasons mentioned already, but also for passenger comfort and driver fatigue. People who suffer from car sickness appreciate the upgrades most.

Being in Washington state, maybe you travel short distances to your favorite destinations and therefore don't experience difficult driving conditions to it's fullest. We travel across the Great Plains and far beyond on each of our trips which places us in all kinds of driving conditions.

And so...there I said my peace. 🙂 Happy Greek Easter!

[j-d]

One of our OP's has long taken the position that stock Ford shocks aren't bad if new or nearly new. It was for that reason I installed the new ones Quigley sent me with my front "axle kit."

[S1njin]

I did ask the truck / suspension shop I’m taking it to if it was worth looking at the shocks while they were working on the alignment. They told me if the shocks are new leave it alone - not worth doing anything w/ them yet.

I appreciated that as I would have forked over the cash if they told me the shocks were garbage. I’m sure the upgraded shocks are better, but the shop told me the stock ones aren’t terrible - especially when new.

I always appreciate a shop when it could take my money but does not.

[whizbang]

Our 24 footer lacks a rear sway bar. And I'm going to leave it that way.

I've owned a number of Rv's since 2001. Yes, a rear sway bar will reduce sway. I concede that point. A stiff sway bar also contributes to porpoising. I will take the sway.

My point is simply this: One can over stiffen a suspension. Stiffer is not always better.

[ron_dittmer]

Just FYI to you people who own a 2007 or older E350 chassis. Ford did not install a rear stabilizer bar. If you have one, it was installed by either the RV manufacture, an RV dealership, or a previous owner. Speaking from experience, getting a heavy duty rear stabilizer bar truly does wonders when you had nothing in back to begin with. So if you don't have any kind of rear stabilizer bar, bump a heavy duty rear stabilizer bar much higher in that pecking order list.

[OFDPOS]

pnichols wrote:
I have absolute proof that the Koni FSD shocks on the rear of our 24 foot E450 Class C are doing something: With the stock shocks back there a latch on our shower door (in the very back) would always disengage after a few miles from the pounding when traveling on our torn up freeways and highways. With the Koni FSD shocks in the rear this now NEVER happens due to their high frequency operating mode.

Of course my experience is with a small Class C that way underloads the rear leaf springs of an E450. I haven't tried the Koni FSD shocks on the front yet, and I'm real curious as to how they will do with the coil springs.

Also, side-to-side roll control has not been affected with the Koni FSD shocks in the rear - it's still excellent due to the underloaded E450 chassis with the stock front and rear torsion bars and with the Koni FSD shocks operating in their low frequency stiff mode during rolling motions.

If those were the OEM shocks, any of the new Bilstein's , Monroe, Koni's shocks would have helped with the slam/pounding. 😉

Heck I can say the same thing about the Bilstein's I replaced on my 2 older MH's I had. Same scenario before replacing the shocks would get the slam/pounding driving over bridge expansion joints or even cracks in the road, once I replaced them with the Bilstein's no more harsh slam...
No more porpoising going through dips unlike what I still get with these koni's ....

[S1njin]

Mine isn’t a much longer rig at 27’ - it has 2800 pounds of CCC available on it.

[pnichols]

I have absolute proof that the Koni FSD shocks on the rear of our 24 foot E450 Class C are doing something: With the stock shocks back there a latch on our shower door (in the very back) would always disengage after a few miles from the pounding when traveling on our torn up freeways and highways. With the Koni FSD shocks in the rear this now NEVER happens due to their high frequency operating mode.

Of course my experience is with a small Class C that way underloads the rear leaf springs of an E450. I haven't tried the Koni FSD shocks on the front yet, and I'm real curious as to how they will do with the coil springs.

Also, side-to-side roll control has not been affected with the Koni FSD shocks in the rear - it's still excellent due to the underloaded E450 chassis with the stock front and rear torsion bars and with the Koni FSD shocks operating in their low frequency stiff mode during rolling motions.

[oldusedbear]

I have a 2001 Coachouse - - 23 footer on an E450 chassis. It rode like a skateboard on cobblestones.

I completely removed the rear leaf spring suspension, and replaced it with a Reyco Granning air suspension. Big improvement but still not what I wanted. Replaced all four shocks with Konis. This was before they had the newer FSD shocks. Still not the ride I was looking for. Had all four shocks revalved at Koni - - spendy, and still not happy.
By that time, the FSD shocks had become available so I replaced all four with them. Pretty decent ride now I think.

More info available for anyone interested.

oldusedbear

[j-d]

X many many! Racers talk about how too much or too little roll stiffness front or rear will cause over or understeer.
Understand the rock crawler perspective too and see them uncouple sway bars sometimes.
The rest of we RVers are just trying to keep it between the lines, clean side up dirty side down so to speak.
And, especially if chassis is Ford, "Sway in the Rear Makes the Front to Steer."

[OFDPOS]

whizbang wrote:
OP.

Delete the sway bars and track bar and your original list is right on.

I am not a fan of sway bars. A little articulation is a good thing. Ask any 4 wheeler. Seriously, if you over stiffen your suspension, you will experience porpoising at highway speeds.

Uhm I like most would kindly disagree with your comment.

We are not out 4 wheeling , rock crawling with our MH's.

We are trying to keep our MH's between the lines , fighting cross winds, trucks passing and pushing us .
Going around corners and not swaying or pulling out of parking lots at angles so we don't drag the tail end yet NOT swaying back and forth doing that etc.

Anti Sway Bars and Trac Bars are not going to cause you to porpoise at highway speed. Bad/worn/wrong type shocks on the other hand will definitely lead to porpoising tho through dips ..

[whizbang]

OP.

Delete the sway bars and track bar and your original list is right on.

I am not a fan of sway bars. A little articulation is a good thing. Ask any 4 wheeler. Seriously, if you over stiffen your suspension, you will experience porpoising at highway speeds.

[S1njin]

You’re right I already have tracking numbers for both bars.