Join Date: May 2009
Location: east coast
Car: OBW H6 VDC, Tribeca, XT6
Feedback Score: 1 reviews
The alignment question first:
If marked properly, it doesn't loose alignment, and you don't need to get one. The only reason not to mark it and install it like it was, is to upsell you. It's like a grown adult not knowing how to make toast.
I attached a picture of a 2015 Subaru Factory Service Manual. It's been the same since 1990 Legacy's, this is super routine and widely known - Step 2 says to mark the alignment, and the installation sections says to line those back up (to retain alignment).
The FSM says to "inspect" alignment - it's not required but at the discretion of the tech. Doing it in your case is quite accurately, asinine. Of all the reasons Subaru would make it discretionary, it's situations like yours.
You're not replacing old, tired components, you're not replacing in pairs/all 4, nor has that new vehicle experienced any strut induced geometry change (ride height) due to the components being replaced. And you're only replacing one and it'll be show room ride height. So again we're back to the beginning where there's no material reason to do this due to one mount/spring.
The FSM says to only do this if the alignment is done. So you're needing this only due to alignment, which you shouldn't need anyway.
Ignore it for now - get the strut work done and juggle that alignment stuff however you want.
If it needs to be done - you'll know it. But you won't, so it won't matter.
Those systems have no interaction with the strut mount and spring, they see no input, data, or signals from them. those are isolated mechanical components that can not impact those systems outside of ride height changes...which you didn't experience and if you did you're putting it back to stock anyway. You might as well get an alignment and reset all these systems every time you change from summer cloth to winter rubber floor mats due to the weight differences. As said, asinine is an accurate word here.
Same here - those systems don't "see" those components, so aside from ride height changes (which you didn't experience and will go back to stock anyway), there's nothing that could require this.
I haven't had to calibrate or work on ones this new, but given the same exact things with ABS, SRS, VDC when they first came out - it was the same thing. "what happens, does that calibration need done, how do you cycle the ABS, reset the SRS, VDC... and in every case the systems, for all their intrinsic complexity, have very limited extrinsic interactions that should be obvious like in your case.
H6 OBW VDC, H6 OB Sedan, Tribeca, Lifted XT6