Stupid shock question
 

I just got a new set of REAR shock similar to the pic below. Does it matter which way you mount them ? Does the rubber bushing thing go at the top or bottom, does it matter ?

http://www.racecardynamics.com/images/zincshocks.gif

The shock boot (the black springy looking part) can go at either end. Rear shocks can be mounted either direction.

thats what i thought, thanks man !

I would think that the boot("springy black thing") would be better on top because if part of the shock were wacked it might be better to hit the chamber not the arm, and it looks better in my opinion. But you can do it either way.

what series shocks did you buy?

It depends on the type of shock.
conventional shocks are mounted boot up.
high pressure gas shocks are normally mounted boot down.

It just depends on what shock you buy.. there should be install instructions
on the manufacturer website.

Yeah my Edelbrock shocks go boot down. It has a giant arrow on them to make sure you do it right.

I know the physics of it is that the lighter part, the boot side, is lighter, thus when needing quick travel moments it can do it quicker than if the chamber side was on the bottom being traveled. I know it's a heavy duty truck ordeal, so i'm not sure if it would make a difference.
On my mountain bike along with dirtbikes the boot is at the bottom because of the weight, but they are alot lighter than truck parts.
As others have said, go with what the shock manufacturer/specific shock recommends for mounting.

^ yep, thats a good way to put it why longtravel is mouted chamber up

yea it depends on the type of shock most of the time, and however the manu. designs it to work best, but yea with some its really no biggie

normal shocks go boot up and only work that way...
high pressure shocks can/usually go boot down.

you cant just mount it whatever way... it has to be right :)

I don't think they came with instructions, they are bilstein 5100's I think.

althought they're front's... my Bilstein's (same series) are mounted boot down... Camburg put 'em that way so I assume that's correct. Dunno if it matters for the rear or not...

where did you buy them from?

I got mine in the RCD kit from national tire and wheel.

I'm almost sure those go boot down.. they are high pressure gas

I was convinced that they go boot down so I really didn't think about it any more. But since I am doing a 31 spline swap I thought I might as well double check since I have to unbolt the shocks from the rear anyway. I called bilstein and they said on all bilstein shocks they get mounted so you can read the bilstein logo right side up.

Which translates into BOOT DOWN.


Edit: While I was on Bilsteins website looking for their phone number I had a thought. The long travel shocks with the reservoirs on top like bilsteins 7100's are pretty much mounted boot down even though they don't really have a boot. Body up boot down whatever you want to call it. When I realized that mounting mine boot down seems less weird. My shocks are basically a shorter version of the 7100's and minus the reservoirs.

My boots on all 4 are up for my HD Bilsteins.

The front shocks have to install like that because the nut pin is at the top.
As for the rears, the writing on them is right side up when installed boot up.

What series bilsteins do you have in the rear ?

Thats weird that mine go down and yours go up and they are both bilsteins. But like the lady on the phone said with the bilsteins as long as the writing is right side up they are on right.

Edit: I was looking around and I saw a front pair of bilsteins that went boot down with the nut thing on the top. Crazy germans.

Q: Can shock absorbers be mounted upside down (rod end down) and still function properly?
A. Most modern shock absorbers utilize a twin (dual) tube construction; in order to work properly the inner of the two tubes (working chamber) should stay completely filled with oil. The outer (reserve) tube contains an oil reserve along with air or a pressurized gas. If the unit is mounted inverted (rod side down), the air or gas in the outer chamber can enter the inner working chamber, resulting in poor damping performance. Therefore, twin tube shock absorbers should not be mounted upside down (or on their side), with the exception of specially designed units that incorporate a gas cell, or cellular gas material, designed to keep the gas retained in the outer reserve tube.