I can't find short enough shocks with the right ends in the right positions, in the right length, (.5" to .625" loop top, 3/8" stem on the bottom) that would work right side up, can they be mounted upside down? Should they be mounted upside down? And, does anybody have a cross reference for Monroe #555003, I want to find some other options for the front. Thanks, P.S. If I can find my camera, I'll do some tech later on this week on Steering column floor mounts.
I would call napa or where ever and give them that number, they should be able to cross reference that number
The valving is different in the shocks that are mounted upside down. As already stated some of the circle track units are made that way to save unsprung weight. Frank
that's not true at all fab. shocks only work in two ways. compression and rebound. there is no way for the shock to distinguish right side up or upside down. it only knows I'm being squished, or I'm being pulled apart. oil filled shocks cannot be mounted upside down. gas shocks can. if the shock has a dust cover on it I would not mount it upside down because it will fill the dust cover with water and destroy the shock.
In the southern hemisphere yes....only kidding. Physically maybe, technically no. Unless they were designed to be mounted that way don't do it. Safety is no accident.....
Actually, to be completly accurate only shocks designed to be run upsidedown can be run that way. Even gas shocks. I do know Bilstien shocks can be run that way as well as higher end Koni shocks. Most mono-tube shocks can be run upside down or horizontal. The problem is with inexpensive twin tube shocks, they have an air pocket whether they gas charged or just oil. The compression valve is usually located seperatley at the bottom of the shock bathed in oil. If the shock is run upsidedown, the air pocket will be around the compression valve and render it useless because little or no oil will go through it. http://auto.howstuffworks.com/car-suspension2.htm
I also believe that most shocks have valving that have different rebound rates up\down and will damage the valves if not in the correct position, most shocks, as revkev6 writes, have dust covers also. A good parts house can look up specs and\or get in touch with a mfg to find the right selection. We have had good luck with O'Reilly Auto Parts and they like and support Rodders.... Bill j.
Here is what Monroe says: 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.
Take a cheapo street shock,and check the stiffness by manually compressing and extending it. Check it right side up,and upside down. You will find it is stiffer when it is right side up. Gas filled race shocks can be mounted in any position. I ran Carrera coil overs upside down,and horizontal, on a race car 20 years ago.No problems.
As I've stated in a previous thread, if you mount your twin tube shock upside down, it will develop a "dead spot" with no resistance in the last inch or so of extension travel.
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