A few weeks ago i had my x in for an alignment and the tech said that my rear shocks were installed upside down. After initially installing my lift (Calmini came with shocks) I thought i had a rough ride in the rear but attributed it to the new stiffer shocks. After the tech told me they were upside down I reinstalled them, yes myself, right side up and now have a much better ride. When I first installed the shocks i was told that it didn't matter which way they were installed but apparently it does matter. Am I the only village idiot?

It depends on the shock manufacturer. I spoke with someone regarding Bilsteins and they said that they were ok to mount either way.
I dont think that works for Ranchos though, which is what Calmini uses in their lift, right?

Pro Comp 3000's aka (Rancho & Calmini) may be mounted either way according to the ProComp Technical help desk .... I had 4 Wheel Parts in , Charlotte,NC call while I was there to verify.

...hope this helps.

The only drawback I see is those pretty blue boots catching water and mud. Makes no sense which way they are mounted... all they do is absorb shock???

Wonder what Steve has to say about this?

The procomp shocks cannot be mounted either way. I had them on my old truck and installed the the wrong way and it road like crapola. I fliped them around and it was much smoother. Most shocks mount boots up.

Then tech support gave out incorrect info.....there are no boots to collect any debris , so we're ok on that issue.

From what I recall if they're the monotube style they can be mounted either way, the other type cannot.

Brent

Why did you call Pro Comp for a CALMINI shock ? Pro Comp doesn't make shocks, they source them from Tenneco like just about everyone else. Each are made to the specs of the company.

I bought Pro Comp 3000 series shocks from 4 Wheel Parts Retail Store....not Calmini shocks, not Rancho shocks.

(However the Rancho's and PC's are the same length both opened and closed) PC's are also listed for the Rancho lift kit as an alternative shock and happened to be about $7 cheaper for each one then the Rancho 5000's.

I mentioned Calmini because 01Salsa referenced them to Rancho's......

I wasn't sure if it was ok to mount this series of shocks inverted and thought the safe thing to do would be to ask. 4WP wasn't 100% sure either , so they called while I was there. Tech support @ Pro Comp told us it was ok to mount them either way. This may not be correct information but it's what I got when I asked and at least I tried to do a little research...oh well.



Namaste.....

Thanks for clarifying that.

A monotube & most cellular gas shocks can be mounted upside down. You would do that if you wanted to reverse the absorption of the spring load from the lower mount to the top mount(frame). Many hard core off roaders do this to have the frame, which is a stronger point, to absorb the upsring movement of the suspension.

Thanks,

The reason i was given to mount the shocks the other way is because when they are upside down the oil that is in the shock settles around the piston end and causes premature failure. It also causes the rough ride because the piston doesn't have anything to compress against. Even if they are gas shocks they still have some oil in them to lubricate which doesn't happen when all of the oil is settled at the lower end and has a chance to leak out. Either way, my ride is 100% better.

You do realize that what you said makes no sense. A shock dampens (slows/controls) the movement by restricting how fast the axle can move relative to the frame. The reactionary force is the same on both mounts, they are either being forced toward each other by the shock absorber (when the suspension extends) or being forced apart (when the suspension compresses). The force on either pivot is the same value, just an opposite direction.

Just remember what Newton said: For every action there is an equal and opposite reaction. The force will be the same at both mounts, regardless of how you install the shock.

Could you clarify what you mean, I'm not sure I'm following you. If the force is the same, what difference does it make which mount is stronger? Either way you mount it, each mount will be subjected to exactly the same amount of force, right?

So what does the path of least resistance have to do with anything? Either way the shock is mounted the weaker mount should break first.

Um, yes it does. A shock is an oscillation damper, and controls movement based on the viscosity of the oil in it, and the design and quantity of the fluid orifices in the piston, it is not just a friction device like you claim.

This is like the 5th suspension related thing you've been talking gibberish about lately, and I'd really like to know where you're getting all of your false information.

It's not false information Ian. You were wrong about the IFS arms, ball joints and what creates front end lift. So it's not gibberish. If you don't believe me I suggest you talk to a suspension specialist. No need to have a fight over this. You just need to be educated a little.

As for the shock, cut it in half and lo and behold you'll see it is actually a piston with valving in the piston head for oil to flow or flow ports in the inner shock body. There is an excellent layman's discussion of how the shock absorber works on Ontario Trail blazers 4x4 club. They go into all the various kinds of shocks. I suggest it worthwhile reading.

I'm giving information to people as questions are being asked, just like everyone else here. I also have a copy of the service manual. I used to be an apprentice mechanic before I found I could make more money sitting behind a desk, so I'm just sharing my experience.

Thanks,

I was not wrong about the suspension lift, you were and everyone agreed (except you).

I'm also correct about how shocks work, and you just verified that in your second paragraph, which contradicts what you said earlier.

Seriously, stop handing out shitty advice here, go to NOR to do it.

They have broken lower shock mounts because they crash into rocks, it has nothing to do with how the shock is mounted.

I'm gonna beat the living crap out of both of you if you don't stop bickering! :rolleyes:

And being a Credit Analyst makes you one ?

I think you only read the 5th paragraph of this page . I suggest you read the rest of it.

It also clears up something from months ago about gas charged shocks increasing spring rate, which no one believed either.

BIBXTERRA,
Over all you come across as a moron. Please quit trying to discuss things you don't understand. Here are some selected quotes:

Basic physics says this is not true. The force of the shock acts on both mounts equally.

This statement makes no sense to me. What would you know about hard core offroading? The frame already absorbs forces from the suspension since the suspension is attached to the frame. The primary reasons to invert a shock are for clearance issues and protecting the shock from damage. If you dent a monotube shock, it's needs to be replaced.

Shock absorbers are spring dampers, they constrict the motion of the system to damp out oscillations between the unsprung mass (tires, axles, etc.) and the sprung mass (frame, body, etc). If it didn't control the axle's movement it wouldn't be doing its job. I don't understand the rest of your statement except to say you continue to reinforce to me that you are an idiot. Every application has different needs. A VW Bug and an F-350 have very different damping requirements. A "standard shock" picked by an engineer for an application is adequate for 99% of the population that does not do anything close to approaching the performance limits of their vehicles. Please leave the engineering to those of us that actually understand it.

Both shock mounts use the same diameter shaft to mount the shock. I don't see how one 5/8" shaft can be weaker than another 5/8" shaft when they are both the same dimensions and material. If they weren't the same this topic wouldn't exist because you couldn't flip the shocks. Under normal use these will last for the life on the vehicle. Offroading the rear lower mounts are susceptible to catching rocks. Force does not follow the path of least resistance. It follows the paths dictated by the kinematics of the system.

Up till now the discussion has been about the rear shock mounts. You start to lose and switch to the front, classic blow hard idiot behavior. The front failure is a fatigue failure of the lower strap mount. I have the same failure. It looks like stress fractures cause by not heat treating the part after welding on the strap for the shock. Ian and I are using Bilsteins with higher damping than the stock shocks. This puts higher shock loads on the mounts and promotes the fatigue failure. It's not comparable to the rear system you have been talking about up to this point.

It's pretty apparent to me you have no grasp of basic physics or engineering concepts. Please leave it to those of us who do. For a layman, I've found Ian to be right more often than wrong. He started breaking parts well before there were alternatives. Since you have only been here a year, you probably have no idea that there was a time when there were no steering kits, idler arm braces or lift kits for the Xterra. It was through sites like this that the aftermarket parts manufacturers started paying attention to us and started making parts to beef up our trucks.

Back to the original question: Monotube and cellur-gas or foam shocks usually can be mounted either way. The gas and the fluid are physically separated within the shock and can not mix internally. Inverting the shock doesn't cause problems. The basic twin-tube design has an up and down. Since it uses an oil sump for the working fluid with gas above the liquid, inverting it allows the gas and fluid to swap places. Then you get air into the working chamber and damping goes bye, bye.