I was having a conversation with a tire/suspension shop and the fellow says the spring is really the "shock" absorber and the shock controls the oscillation/frequency of the "shock". Ok...maybe I get it...maybe. The reason for the discussion is on my 49 Chevy pick up, V/8. TH350/AC, etc, with an aftermarket A-arm front suspension and lowered rear leaf springs, the truck rides too harsh. I have 325lb springs in front with cheap gas shocks and TCI 2" lowered truck leaf springs with non gas shocks in the rear. Freeway driving and long swoopy curves...no problem - hit a bump in the road and I have to go back and pick up my dental fillings. Adding weight does help some in the rear but this is a non-load hauling truck...just a hot rod. I want the ride of a Cadillac - a nice ride not a pro touring type thing....c'mon you know what I mean. My tires are 235 60 15 front and 275 60 15 rear. So, does shocks get me there or springs? Or the right combination of both AND how does one figure it out? Thnx
Whats the shop mantra? "If you can't dassle them with brilliance...baffle them with bullshit?" I think the "expert" is an expert on setting toe-in...not suspension theory.
Try a good quality gas shock in the rear. If that does not fix it, experiment with removing a leaf or two. Shock absorbers dissipate unwanted excess kinetic energy (movement) in the suspension, by turning it into heat, via the friction of passing a perforated disc through oil. The gas help keep the oil from foaming. It does sound like your rear shocks are not up to the task, and possibly that your rear springs are a bit too stiff. Think soft spring, stiff shock.
Spring hold the car up, shocks and tires stop the bouncing. If there is too much spring, it can induce bouncing. If the tires have too much air, it can induce bouncing.
If not for the friction in the spring leaves and shackles, your truck would bounce for hours after one bump if it did not have shock absorbers. Shock absorbers resist movement, especially fast movement, and so quickly cause the suspension to stop moving after you hit a bump. Spring friction alone does not stop the bouncing quickly enough. Have you tried a careful test drive with the shocks disconnected? Should tell you if it is the springs or shocks that need rethinking. Also make sure your suspension is not bottoming out.
A quick and easy test for the shocks: find a short road that gives you the ride that you are unhappy with and drive it, then remove the shocks and drive it again. If the ride is up to your standards, change the shocks, if not, then the springs are also too stiff. Sounds to me that you have a combo of too stiff a shock and too stiff of springs. As jrblack30 states, springs hold up the weight and the shocks control the movement.
Spring- absords road shock Damper ("shock absorbers")- slows spring. Shocks should actually be called dampers, but we call them shocks.
rpu28 That is what we will do this weekend. Just a quick ride around the block... "Think soft spring, stiff shock"...will take under advisement....
Google conversion says 325lbs is 0.1625 tons. If thats right the coils are way too soft. My guess is that 2 ton coils with adequatley paired shocks will make it ride ways better. As for the rear, if weight helps stiffer shocks will work. BTW, your expert sucks. LOL It would be fun if i was goin to give advice on engine tuning to the same guy he gives advice on suspension....Epic fail, hahaha
It is possible that the springs are just too stiff for the shocks to handle, but otherwise fine, so try the shocks first.
Yeah, just noticed the 325in-lb. The front springs might be too soft for this application. Something closer to 450in-lb. to 500in-lb. would likely be better.
This is a Mustang II "type" suspension. I started with 400 lbs and had to take my head out of the ceiling after a bump. Went to 275 - too low and too soft. Actually couldn't drive it due to fender/tire clearance. Went to 325 and better of all three but still want a better ride.
Buy adjustable dampers. You can adjust how fast or slow the rebound and compression will be. But a LOT more money.
It sounds like you are on the right track, the leaf springs might be too stiff. Have you checked the bump stops, if you are bottoming out onto the bumpstops, this will in fact act as a much stiffer spring and give you the same effect. I would check that first.
That's essentially correct. Springs hold the car up and soak up bumps and shocks, dampeners as they were correctly labeled earlier, control the spring, both oscillation and rate of spring movement. That is why shocks are WAY more important than springs when chasing ride quality. 325 is pretty close to where you want to be. I ran 275s in my AD truck and they were perfect for me. How much air pressure in your tires? Try 30 psi
So the problem is not the coils being too soft? thats odd. I'd get cylinders and accumulators and chock the coils out the window Might seem like a joke now but i guarantee you it will actually ride like a caddy like you were sayin earlier.
Based on the fact you said adding weight helps, I would suspect your spring rate is to much plus, you're either bottoming out your suspension or the shocks are bottoming out. You can get a softer ride by taking a leaf out since your leaves were designed to haul a quarter or half ton, if they're the stock leaves. Check the travel of your shocks too.
But then again, on modern veichles they have coils that are ridicolously soft, and tuff shocks. So maybe your problem is more on the shocks side thsatn on the coils. IOf the coil is very soft the wheel will move a lot when hittin road inperfections, so if you have a soft shock you'll keep bouncing, while a very stiff one will stop the rebound givin you the ride you want. Hope this makes sense.
Softest springs to get the job done . Which is hold the car up and balanced. Stiffest shocks that you can stand . To control the perfectly balanced bouncy spring. I'd say 90% of the time you're going to be happy with that ride quality on the street. Springs are a cushion, shocks are cushion control
Harsh ride is usually defined when over springing the vehicle, meaning that the spring chosen is stiffer than required. The front spring should be slightly stiffer than the rear for comfortable ride. Ride can also be adjusted with tire air pressure too but the first step is to determine if your hard ride is bottoming out the suspension or just too stiff. On a rough road just bottoming out the shocks from incorrect installation can produce a rough ride. To do this easiest is to check the shock travel first, If you have covered shocks go to the hardware store and purchase a length of foam insulation used for water pipes about 2" ID. You are going to use portions of this as a shock travel indicator sleeve. Cut the foam tube into 4- 2" wide donuts to wrap around the lower body of your shocks. Clip over the lower body and wrap with tape or a zip tie so that it is snug on all 4 corners and move the foam donut up until it strikes the shield. Take the vehicle for a quick cruise over the roads you are having an issue with and then look at the travel of the suspension as it displaced on the foam donuts. They will move to indicate the maximum travel you have gone thru. If you travel is less than 2" and your shocks have not bottomed out you are sprung too stiff. If your shocks do not have dust shields you can do the same check by wrapping a zip tie around the exposed shaft to determine the travel. Tell me what you get and we will go from there.
I had the same problem with my '41 Ford fordor. Removed a leaf and got rid of the gas shocks. Too much shock and the rear will pick up on bumps. Also too much sway bar in the rear will make the rear jump, especially on one wheel bumps. It took me years to figure out how to soften the ride on my '41. The above solved it for me.
Rear sway bar...hmmmmmmm...yes I have one and I thought this may contribute to this issue as well. I'll have them disconnect it and see what happens. I will figure this out and when I do, I'll keep it to myself.
I have KYB Gas-a-just shocks on the rear of my daily 52 chevy 1/2 ton truck, for many years. These are a combination of hydraulic and nitrogen gas shocks. Easy and gentle cushion under light load, but gets increasingly firmer with heavier loads or movements. I also removed the smallest leaf of the springs and have 2" lowering blocks. Rides smooth around town, firmer on the freeways and can handle rough dirt roads, regardless if I am fully loaded, partially or have an empty bed. They adjust to anything and were cheap, too.
Like 31 Vicky sez......... Springs are a Cushion, Shocks are cushion control ! Now, If it were A Ford.............. The Springs would be in The SEATS ! Have A Great Day.
check your travel like dick explained but taking out leaves as others have suggested it's always the best way if you take out too many you end up with spring wrap causing the rear to hop on acceleration and braking some times it's better to shorten the leaves in the rear half to soften it and keep the frt stiff.
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