auto polarity reversing relay

Hello all. I was doing an internet search for this information and came across this board. All I can say is HOLY $#!T I can't believe the wealth of info here!! I looked through the topics but couldn't find any info on what I am looking for so here I am. I am looking for a relay that will have a 12v positive input, but that will automatically switch between 12v positive and 12v negative output. Let me explain the application as well just in case someone might have a better suggestion. I have a customer that is installing a hydraulic ram on his dump truck. It has a 12' throw on it and he is going to use it to control the gate lock on the dump body. The problem is... the ram is activated by 12v but it requires reversing the polarity to extend or retract it. (A+ with to 12v+ and ground wire to 12V- will extend the ram. A+ wire to 12v- and ground wire to 12v+ will retract the ram. The customer has a Touch Tek VI control box that he purchased from AW Direct out of Berlin, Ct. (www.awdirect.com) The box has a soft touch control pad with a remote mount relay box. (AW Part # TK6) One switch has a timed relay which is intended for use with a gun lock but he wants to be able to wire it up to the ram control so that it isn't on constantly. Essentially, what I am looking for is a relay that will automatically switch polarity once the switch box relay times out. I called Granger and a couple of other companies but have been told "Good Luck" in a nice way. Any help with this problem would be greatly appreciated. Thanks to all who have taken the time to read this. Chuck P Pike County Communications Matamoras, PA 9845)699-9361

See if this thread on reverse voltage for boat is something like what you're looking for- you may need to add some more to it if you're controlling it with just one line, and if you need it to time out on the retract mode also.