Manage My Unlimited Wash Club Account (Silverstar)

This form is only for customers in Sioux Falls or Sioux CIty. If you are a customer in another market, please visit and navigate to your specific store on the map.

By checking this box, you are providing your electronic signature and express written consent to receive SMS marketing text messages from Mammoth Holdings, LLC and/or its agents or vendors, and you confirm that you are the customary user of any phone number you submit. Text messages may be sent using an automated dialing system. Your consent is not a condition of purchasing any goods or services and may be revoked at any time by responding STOP to any SMS text messages you receive. Message and data rates may apply. Additionally, you agree to our Terms of Use and Privacy Policy located at and consent to our collection of certain location, usage, and related information. Standard state sales tax may be billed in addition to the item total depending on the location of the car wash you select.