Outer Limits 4x4 Board

Just a very general question with no specific model/parts...

I want to fit some fully sealed, zero gas, 100% oil shocks upside down.

(so the metal stem is at the top of the shock mount and the oil res is at wheel side)


Other than the added weight to the moveable wheel, is there any sort of no-nos about shocks? Gas,foam or oil?

Of the regular type shocks, the only ones you can run upside down are the remote cannisters and the monotube type ones. If you run the oil shock upside down the valves will partly run through air instead of oil.

If the shocks are pressurised (i.e. self extend with a decent amount of force when off the vehicle) then they're probably high pressure gas with a seperator piston and run fine upside down.

If they don't self-return, then no they can't run upside down as the internal air pocket will stop the foot valve from working.

I think we need specific shock info.

Generally, no. Edelbrock shocks, OME LTR's, and Bilsteins can go in upside down.

running shocks upside down can root their valving too. The Australian Rancho distributor used to (may still?) suggest upside down mounting RS9000's to get the fitment right, but I've had 9000's dyno'ed upside down and the valving is whack- compression valving dissapears.

Steve.

i ran Rancho's upside down to protect the adjustment nut thingy, they were fine.

They were fine as in they didn't leak or they were fine as in they valving was correct?

They do "work" in that they dont leak upside down.

They definitely no not valve properly upside down. I've got the dyno sheets to prove it. Basically, compression valving vanished. (They also did strange stuff as they changed direction - all the valving vanished altogether, as though the piston was running in air. Dad ran his 9000's upside down in his 80 series (front) for a while and that was borne out in the vehicles behaviour.

In a buggy or leaf sprung car, they might be ok, but there's no way they are working the way Rancho intended.

Steve.

Even just by cycling them by hand while upside down you can see how the valving is stuffed up.

Gwagensteve wrote:all the valving vanished altogether, as though the piston was running in air.

Funny that.

Well, it'd be the foot valve running in air, but I thought that was getting a bit technical to explain.

Steve.

Gwagensteve wrote:Well, it'd be the foot valve running in air, but I thought that was getting a bit technical to explain.

Steve.

Depending on the oil fill, if the foot valve is running in air the rest of the oil can just move with the main piston instead of through it.
Hence no damping until you either froth the oil or get enough shaft movement to get oil back to the foot valve.

lolergram wrote:I want to fit some fully sealed, zero gas, 100% oil shocks upside down.

(so the metal stem is at the top of the shock mount and the oil res is at wheel side)

To me this suggests the reservoir is at the bottom and the exposed shaft is at the top, which is the correct way of fitting them.

Gwagensteve wrote:They were fine as in they didn't leak or they were fine as in they valving was correct?

They do "work" in that they dont leak upside down.

They definitely no not valve properly upside down. I've got the dyno sheets to prove it. Basically, compression valving vanished. (They also did strange stuff as they changed direction - all the valving vanished altogether, as though the piston was running in air. Dad ran his 9000's upside down in his 80 series (front) for a while and that was borne out in the vehicles behaviour.

In a buggy or leaf sprung car, they might be ok, but there's no way they are working the way Rancho intended.

Steve.

In my Sierra i have shocks which are a bit too stiff, could i flip them and they would be softer? Dodgy fix i know, but could it work?

And to the other people who fix shocks upside down, doesn't the dust guard fill with crap??

Mike

No,

Its typically Bilstein etc that get used upside down, and you can get concertina boots for them.