When my hood wouldn't stay up, only one lift was bad, but I changed both anyway. If you take one off, most auto parts stores can match them. Just make sure to prop the hood up with something so that it won't come crashing down on you fingers... Ron
I took mine off and went to parts store...it was fun since no number match. Finally seleced a pair which had everything "eye ball" the same. Length of overall unit and stroke travel most important. Wish I could remember what vehicle final selection was for...but...! The ones I now have have a little more pressure to them, but work great.
So, I bought a new lift shock when I first got the car last fall and the hood stayed open a lot as the car sat in garage for about 4 months while I sorted out a tranny swap, then head gasket replacement. Noticed the hood started falling a lot, thought maybe I wore out the new one leaving hood open so much. I was able to warranty the shock, but the replacement is hit or miss. Sometimes it'll hold while I check fluids, run to operating temp etc, (I was chasing an oil leak most recently) Sometimes, I open the hood and as soon as I let go it begins to fall. Seems the one shock design is the flaw anyway - has anyone discovered a good solution other than the broom handle or vice grips on the strut rod? I considered fabricating mounts for a second shock, but before I go that far, I'd like to hear any better ideas!