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Old 08-01-2021, 07:21 PM   #1
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Sumo or new shocks

Which reduces the jolting more at stiff bumps on a W22 Chassis, Sumo Springs or new Bilstein or Koni shocks?
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Old 08-01-2021, 07:33 PM   #2
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I think Sumo “springs” are likely to provide more relief from jarring. Technically, shock absorbers is a misnomer because their primary job is to reduce the frequency of rebounds, and not absorbing “shocks” from road defects. Worn out shocks allow the bouncing up and down to continue longer than do new ones.
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Old 08-01-2021, 08:33 PM   #3
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When I installed the sumos on our Ford chassis, I definitely noticed less jarring going over things like expansion joints and less side to side sway. I also gained about an inch of ride height.

When installed the Koni FSD’s I immediately noticed a more compliant ride in every respect. Shocks won’t help with things like sway, but the ride over every road surface was dramatically improved.
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Old 08-02-2021, 03:36 AM   #4
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If you don't know the age or condition of the shock absorbers you should change them before doing any other suspension work. Shock absorbers are maintenance items. Gadgets to improve ride and handling cannot compensate for worn shocks.

I put Bilstein shocks on mine and I am satisfied with them. Other prefer Koni shocks. Pick your poison but do the shocks first then decide if you need anything else.
2003 34' Georgetown on W20 Workhorse Chassis. UltraRV power mods. Front Sumo Springs, Rear P32 Sumo Springs, UltraRV Track Bar.
1998 Jeep Toad.
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Old 08-02-2021, 06:46 AM   #5
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I put Sumos on the front, after switching out the original Bilsteins with Konis. The ride difference with the Konis was immediate and I felt it softened the ride. Not sure the Sumos improved the ride that much, but they were easy to install and relatively inexpensive so I gave them a try.

However, neither will remove the jarring input from a bridge abutment.
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Old 08-02-2021, 08:10 AM   #6
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We have the Sumo's on our front end and as stated earlier they help a lot with the swaying from side to side but normally only come into play on a jarring incident that exceeds the shocks ability to absorb (could be due to a shock that is worn out). We replaced our Bilstein's recently with new Bilstein's and the responsiveness of the new shocks were improved over the old shocks that had over 50,000 miles of abuse. The biggest impact on our jarring was not new shock or Sumo's but was reducing our tire pressure closer to the minimum PSI for our axle weights plus 5 pounds for my own piece of mind (prefer a firm sidewall to reduce tire overheating).
2007 Newmar Baystar; 3201; miniature schnauzers and labradoodle. SumoSprings Front; Safe-T-Plus;2016 Fiat 500; Roadmaster Falcon 2;Demco SBS DUO Braking System;TST 507;Bilstein shocks; Garmin RV 785
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Old 08-02-2021, 10:36 AM   #7
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I guess that would depend on how bad your old shocks are. If they're leaking they need ti be replaced. I replaced my original shocks with Bilsteins. Can't say I noticed much difference, perhaps a little less sway, but my original shocks only had 14k miles on them (but were 15 years old) and may have been perfectly fine. The Sumos did soften the bridge transitions for me.
2004 National Dolphin LX 6320, W-22, 8.1, Allison 1000, Front/rear "Trac" Bars & Anti-sway Bars, Sumo Springs, Roadmaster Reflex Steering Stabilizer, 2005 PT Cruiser Toad
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Old 08-02-2021, 10:44 AM   #8
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Thanks all. We have 55,000 miles on what I believe are the original shocks. I'll do the shocks first and the see if the sumos are needed.
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Old 08-03-2021, 08:37 PM   #9
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Actually not so, 'good shocks' can have diff valving for compression (hits) vs rebound but ALL shocks 'dampen' the action of the springing in BOTH directions.

Some 'good' shocks have both preload and some can have pre-load adjusted as well as how hard or easy the 'valves' will open to allow more oil/fluid inside to flow.

** a 'closed' valve does not allow oil/fluid to flow and causes 'harshness' or restricted movement of suspension - thus valving is the most important aspect of the typ simple mh shock, open valve obviously allows fluid flow but also can have multiple orifices for fluid to flow and valving can open them in a progressive manner - so valving can be fairly complex just in itself.

They can also have rebound tuning as well, but a PURPOSE designed shock will be 'tuned' in both compression and rebound for the 'loads & speed' of compression and rebound of the mechanical parts of suspension.

So a 'good' tuned shock both 'smooths' compression AND rebound and 'should' make for a better and smoother ride - but essentially they are to absorb the harshness of an uncompensated mechanical spring which has ZERO dampening generally.

Check out either racing shocks or just off shelf off road motorcycles for the sophistication that shocks can have, it is a science all in itself !

PLUS, you CAN buy shocks with aux springs so they can have an even greater effect on suspension tuning, but simple Bilstein and Kona shocks, it is up to the 'engineering' (if any) of the engineers/tuners, but do not expect too much and NO tuning at all.

Just to give info, shocks from OTHER uses (from a catalog) can be used on mh, but you must know the total max and min lengths of travel, as well as springing amounts & weight of vehicle involved - just so to NOT destroy or hurt things if trying for some tunable shocks - non trivial stuff - but could be very rewarding - and we have just been talking about simple UP&DOWN suspension movements, no dynamics of side-to-side, etc !!
Originally Posted by edgray View Post
I think Sumo “springs” are likely to provide more relief from jarring. Technically, shock absorbers is a misnomer because their primary job is to reduce the frequency of rebounds, and not absorbing “shocks” from road defects. Worn out shocks allow the bouncing up and down to continue longer than do new ones.
2007 WhineyBagels W24 54k mi Allison 2100mh
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