Installing Monotube Shocks Increases Ride Height?

[mechtech2]

What you guys are seeing is after the car is on a lift, the ride height will be a bit higher after installing low pressure gas shocks. But this is anytime a car is on a lift.
And some erroneously attribute this to the shocks.

 

[martinq]

Originally Posted By: mechtech2
And some erroneously attribute this to the shocks.

There is the suspension/tire bind that happens when dropping the car back on the ground. This goes away once you roll or dirve the car and let is settle. Some extra spring can be gained from new suspension bushings especially if they are tightened before the suspension is loaded.

But what we're talking about here is adding spring-force to the car from a gas-charged damper. This will always increase the ride-height even if is negligible. Same happens when you add air to your tires. +1 psi will give you lift.

 

[martinq]

Originally Posted By: UG_Passat
the replacement.. is a monotube, which is a high pressure design. It does take more effort to compress them.

Twin-tube or mono-tube design should not affect the amount of rod-force if the gas pressure is the same. Mono-tubes do tend to run much higher pressure though.

 

[The Critic]

Originally Posted By: martinq
Originally Posted By: UG_Passat
the replacement.. is a monotube, which is a high pressure design. It does take more effort to compress them.

Twin-tube or mono-tube design should not affect the amount of rod-force if the gas pressure is the same. Mono-tubes do tend to run much higher pressure though.


So by that logic, when I replaced the blown twin-tube struts in the front, I should see an increase in the ride height.

 

[martinq]

Originally Posted By: The Critic
So by that logic, when I replaced the blown twin-tube struts in the front, I should see an increase in the ride height.

If the new struts are gas-charged and the old ones were not (or have lost it) then there will be a change. Should you see it? Don't know but it should be measurable with the right equipment.

Before you install the new struts, try to measure their spring-force on a bathroom scale (or similar). Compress the strut part-way and hold it steady on the scale. Both struts should give similar values. You'll need to weight them and subtract the value of course.

 

[The Critic]

Update: I installed the new KYB Excel-G struts on the front axle. The ride height did go up a bit, but not a lot.

The rear is still a bit higher than most Previas I see on the road. Here is a picture:

 

[martinq]

Thanks for the pic and the update. How did the rod-pressure on the front struts compare to the rear. Similar?

I gotta say that there are NO Previas that look anything close to that up here (if you could find one). As ugly as they are, this one's a beaut!

 

[The Critic]

Originally Posted By: martinq
Thanks for the pic and the update. How did the rod-pressure on the front struts compare to the rear. Similar?

I gotta say that there are NO Previas that look anything close to that up here (if you could find one). As ugly as they are, this one's a beaut!


The new front struts are fairly soft and the rods can easily be compressed. The rear shocks required putting all of my body weight onto the shock, and even then, I was barely able to fully compress it. After break-in, the rears ride fairly taught while the front is a bit softer than I expected. Overall, the van rides/steers/handles great....it's just the ride height that is a slight concern.

 

[martinq]

Originally Posted By: The Critic
Overall, the van rides/steers/handles great....it's just the ride height that is a slight concern.

By the look of it you've increased the payload capacity.