Rubber on rear springs

[altheflip]

Hey guys just installed Eibach springs on the rear of my '07 tahoe. I noticed that the stock springs had blue rubber wrapped on the coils. Do I need to transfer them to the new springs? Did my research and saw a couple of them with and without the rubber. Any suggestion would be greatly appreciated.

 

[Fyrcaptain]

I believe those ars for sound isolation....

 

[iwaslowr]

If you are referring to the rubber that is covering a few of the coils on the stock springs... I left that alone when installing my Bell Tech kit, but did retain the upper and lower isolators (for now).