Strut lower seat required?

[JCrump]

My car came with coilovers already installed which need replacing. I have no need for adjustability and have heard that swift spec r springs offer comparable if not better performance anyways, so I went with them along with bilstein b6 struts. My question is this: do I need to install the lower rubber spring seat that sits between the strut and the spring? I saw one video saying to take it off of your oem struts and put it on your new ones, but then another one where the dude didn't install any at all on his koni yellows.
I was able to find what seem to be replacement oem ones online, part # CV1Z-5414-A, but it only says it's for the front-left strut. Are they identical between the front left and right? My springs got here today and I don't feel like waiting for these if it's just something for a slight decrease in nvh or something like that.

 

[Jabbit]

Can you post a screenshot of exactly what you need? I have a full stock suspension setup if needed.

 

[JCrump]

Can you post a screenshot of exactly what you need? I have a full stock suspension setup if needed.

This black rubber piece that his thumb is on is what I'm referring to. That'd be much appreciated if it's a necessary component

 

[Jabbit]

This black rubber piece that his thumb is on is what I'm referring to. That'd be much appreciated if it's a necessary component

Not sure what that is but I'll check my stock struts/springs and see if it's on there and in good condition.

 

[Intuit]

I don't see why it wouldn't be installed. It may play a role in helping to prevent abrasion damage to the paint. Paint is *extremely* important on a spring.

 

[TyphoonFiST]

That's the lower spring isolator* yes I would replace them with the Spec r springs also.

Sent from my SM-N975U1 using Tapatalk

 

[JCrump]

Not sure what that is but I'll check my stock struts/springs and see if it's on there and in good condition.

I actually went ahead and ordered a pair with overnight shipping. I appreciate the offer though. Thanks for the help y'all

 

[TyphoonFiST]

See if deactivating the Hill start assist and driving it for a bit. Then stop and reactivate it to see if it helps remedy the issue. This can be done in the Sync menu on the touch screen*