SugarHillCTD wrote:
Bill,
Our Chevy has just over 20,000 miles on it and the OEM shocks are not doing what they should be. There are some situations where we get too much side to side movement, not necessarily sway.
I think that the loads we put in the bed of our trucks just overwhelm the shocks. Most of us have increased spring capacity so OEM shocks are unable to control this greater energy- that isn't what the engineers designed for. They were looking to control their designed load while hitting a $ point.
On a previous truck I changed to Rancho 9000 shocks front and rear. Big difference in handling with the TC loaded.
BUT
As you can imagine our salty winter roads were very hard on the adjustable shock. In a couple years when I traded the truck in the adjuster was rusted solid.
New shocks are planned for next spring, but they won't be OEM or externally adjustable.
John
I am far from an expert, but it seems to me that this is using a shock for a role for which it is not designed by stiffening the valving rather than installing larger shocks with the proper valving to get the control required.
I am not saying that tighter valving isn't going to resist movement better, but it's also going to increase the amount of heat that needs to be dissipated. Without a larger surface area to get rid of the heat, more oil (by using a reservoir shock, which would give the oil more time to cool), or a larger diameter shock that has more surface area, no matter how well the shock performs when cold, the increased control only lasts until the oil is too hot and thin to perform as it should.
From reading on here, it seems that the shock manufacturers have a marketing problem. Rancho's RS9000 is a popular shock for many applications and its dial isn't a solution for properly sized and valved shocks for the application.
Those who are willing to spend big dollars on shocks would probably be far better off with a larger diameter, monotube, reservoir shock that was properly valved for both the heavy loads we carry and the type of springs that your vehicle uses. I am not an engineer but I know enough about the dynamics of suspension design to be skeptical that the unique application for which we use our trucks suggests that a shock more specifically suited for what we're doing would be a better match. This also means that the valving would be different based on not only the spring rate but also whether our trucks are equipped with coil or leaf springs, the load, the terrain, and the speed at which we expect peak performance.
If side to side control is desired, my intuition also suggests that stiffer (aka, shorter or more likely, larger diameter) sway bars would be a far superior upgrade to simply installing a stiffer shock that would slow the deflection we seek to control. Using a shock to essentially raise the spring rate by providing more resistance to motion is a band-aid. Stiffer springs would sacrifice ride quality for the up and down motion of the suspension rather than controlling articulation, which is what sway bars are used for.
Shocks aren't magic. They are there to control motion of the springs in a specific direction. Will stiffer shocks reduce roll? Sure. But why sacrifice ride quality for some increased suspension stiffness?
If shocks really could provide the type of roll control many here claim to use them for, stiffer springs would probably achieve the same result more effectively.
It may very well be that the market isn't producing a stiff enough sway bar and thus a stiffer shock is the best-available solution, but if we really want peak performance, the proper spring rate for the weight, controlled by the proper diameter sway bar, and damped by the proper shock rather than the stiffest one, would probably provide the best performance.
The proper shocks are probably quite a bit more expensive than the stiffest band-aid, but they are also revalve-able and rebuildable and would stay with us for a long time.
These are just the random thoughts of someone with some experience but no hyper technical knowledge of that which is required. Consult someone who can put numbers to this analysis and I suspect your money would be much better spent. And those people and products ARE out there--we just need to seek them out. Off-road racing has really improved the range of products available in this area, but these products are not well marketed so you will have to seek them out rather than just buy something that bolts on.
