Heavy duty shocks on light duty vehicle?

chevrolet
uplander

#1

Hi there. I’m worrying to ask a question about an Opel Zafira. I’ve put the Uplander as my vehicle because it’s the closest to the Zafira (which is GM/Chevy in Europe).

My question is this: is it reasonable and would it help to install heavy duty shocks on a regular, light duty vehicle? You see, I’m an American but live in a Balkan country, with lots of pot holes, speed bumps and generally bad roads. I’d like to save my car some wear and tear and this is one idea. I know, I could have bought a 4x4 but that wasn’t an option for me.

So I’m wondering if anyone has any insight.

Thank you!


#2

I’ve had the same thought on this issue, and the first assumption I made is that doing what you propose would lead to a very stiff ride. The relative light weight of your vehicle compared to the truck or jeep the shocks or struts were designed for would mean all the other suspension and drivetrain components would take more force from every pothole impact.

In the end, I opted to find struts for my car that come with a lifetime warranty on parts, because I don’t enjoy a stiff ride.


#3

This stiffer shocks is going to transfer to the rest of the vehicle. The problem is - if the vehicle is medium to light duty then the places the struts/shocks connect to may take a lot more punishment then they were designed for.


#4

“Heavy Duty” is a sales pitch. Are you comparing the bore diameters of similar models or booster springs or nitrogen pressurized vs non pressurized.

http://www.lcool.org/technical/shock_absorbers/shock_absorbers.html

And there is a great deal more technical drivel available on the www re shock/strut engineering.


#5

I would use high quality shocks, not heavy duty ones. Koni, Bilstein, Sachs, KYB, Tokico would be on my list.


#6

Thanks everyone. You’ve told me things I wouldn’t have thought about. I’ll check into the high quality shocks and make sure I’ve got what’ll last longest on these roads.


#7

My guess is that the “heavy duty” term for shocks means they would (supposedly) have a longer useful life, handle more bumps for a longer period of time before failing, not a different performance when going over a bump. Heavy duty springs would probably perform differently over a bump, but doesn’t seem likely for shocks. Heavy Duty shocks may still make sense in an area where the roads are really rough, b/c they’ll last longer. Do decide depends what price premium they incur.


#8

The ‘heavy duty’ shocks I’ve seen have much harsher damping. I put a set on our family’s car, ruined the ride. “Heavy duty” and “high quality” are two very different things.

edit - you’re right, many HD shocks will last longer. But you may wish they didn’t!


#9

My knowledge of living in Europe is admittedly dated . . .

But I believe “lifetime warranty” is not legally permitted over there

That said, I agree with you and most of the others . . . stick with regular shocks. This van doesn’t need HD suspension components

I’ll partially differ with @texases . . . I recommend against Tokico. My experience has been they make for a stiff ride, and they have a very short lifespan. Sachs and KYB are good choices, in my opinion


#10

I’m inclined to agree. The shocks are there to absorb the energy from the impacts and isolate them from the body to the extend practicable. My admittedly limited experience with heavy duty shocks is that they ride stiffer… meaning they transfer more of the energy from the bumps throughout the vehicle rather than isolating it from the body. Think of shocks as “sacrificial”. They wear out from the bumps so that the vehicle doesn’t have to.


#11

In earlier days, I would put firmer shocks on my cars than the original equipment type. My reasoning was that the springs were probably worn from age and the firmer made up for that. I also preferred a firmer ride to the overly soft willowy ride of the cars I owned in the 1960s and 1970s. I also thought that the firmer shocks improved the handling. This was particularly true on the 1965 Rambler Classic that I once owned.


#12

Wouldn’t it have been better to buy a shock with helper springs? Most companies had that as an option.


#13

I don’t know that shocks with helper springs would have been much different as far as ride is concerned than stiffer heavy duty shocks. I did put helper springs on rear shocks when my brother and I owned a small 12 foot runabout boat and we.loaded (or possibly overloaded) the boat and car with camping supplies. I also had a 1954 Buick that had lever action shocks in the rear. To firm up the ride, I put air bladders inside the rear coil springs and inflated them.
In.the vehicles I have owned since the 1970s, I think the manufacturers have designed better suspensions and shocks or struts to give a better balance between handling and ride. However, I still prefer the firm seats and ride of our 2003 Toyota 4Runner. We can make the trip of 375 miles to visit our son and at the end of the trip I don’t feel tired or stiff. I have made trips of the same distance in softer riding vehicles and I am worn out and stiff after the drive.


#14

Shocks need to be matched to the spring rate in order to not adversely impact handling. The shock helps to keep the tires in contact with the road surface by damping the spring rate. It’s somewhat less critical on leaf spring designs because the interaction between the leaves produces some inherent damping all by themselves. Coil springs are much more reactive. There is a fair amount of latitude before you start having a significant impact but if you over-dampen you risk having the tires skip over bumps rather than follow the contours and this can lead to serious handling issues. Somebody already pointed it out but “heavy duty” doesn’t mean “more robust design with the same performance characteristics”. You’re better off buying a higher quality shock designed for your application than to second guess the designers and substitute in one with different performance characteristics…


#15

I know that some shocks can be adjusted to several different levels of damping, without having to remove them from the car. The KYB’s I used on my Miata have 3 or 4 choices, set with a knob. If I was buying shocks for the situation you laid out I’d try to find adjustable ones.


#16

Those adjustments usually control preload, aka spring tension. On something as large as a car, it’s a fine tune adjustment you might not even perceive. I see them frequently on motorcycles, on the rear wheel.


#17

Not for cars:

http://www.jegs.com/i/KYB/575/741021/10002/-1?CAWELAID=1710915948&CAGPSPN=pla&CAAGID=15769068431&CATCI=pla-176568835991&CATARGETID=230006180003463682&cadevice=c&gclid=EAIaIQobChMI1ui5_JnG1wIVxSOBCh1r9wgKEAQYBSABEgIjR_D_BwE


#18

KYB says the adjustment controls the damping, according to the website https://www.kyb.com/products/agx/
That’s one of the reasons I bought them.