Welcome to 2CarPros, and welcome to the wonderful world of aftermarket parts. The new parts may "fit" just fine on paper but then in the real world they don't work or are rated wrong. In this case it's possible that is the problem and they are not rated correctly, or one may be defective. Normally it takes both working to support the load, if one is bad, the load drops.
The old ones are the same way, it's possible that one leaked enough that it was on the verge of failure and simply disturbing it by allowing the ram to go to full extension or laying it down was enough to finish the job.
OEM are not the only choice for parts but there are many times they are the best choice.
In this case it looks like the OEM parts are around $25.00 each from Subaru, they show
Parts #57259AJ03A Left and #57259AJ02A Right. If you wish to look online, parts. Subaru. Com will show you local dealer and pricing on parts.
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Sunday, May 19th, 2019 AT 6:49 PM