The Techron I used was from Costco sold in the 6 pack. The bottle says safe to use every 1000 miles. As a teenager I worked at a chevron station and the owner told me that the premium gas had 3X the Techron as the other two grades. I never fill up at Chevron so I thought adding some Techron would keep the system clean. After receiving the UOA I informed Blackstone of the Techron use and they recommended not using any this OCI, so after 8K miles I will send in another sample and see if anything changes. Another variable is E85, I did mix 4 gallons of E85 in my tank 5 different fill-ups during the sampled OCI.