Auto RX works best at full, normal operating temperature. Product works under flow and temperature. With that said, maximum cleaning potential is achieve running the motor continuously over time, highway miles are great. However that is not to say that the product won't work under short driving intervals. It will just take longer. I too, have run a full dose of ARX for 3000 miles. However, I did it after two cleanings and a visual inspection that the motor was spotless. ARX did not wear out over 3000 miles. I did several filter changes and inspections over the 3000 mile run. Just follow the ARX.com web site for applications and you'll do just fine.