Review on 🔌 Autolite Iridium XP XP5363-4PK Spark Plug Set, Pack of 4 by Bubba Ott

After about 70,000 miles on my Mustang GT I noticed a slight decrease in fuel economy and the need to downshift from 6th gear earlier than usual at lower speeds . Replaced factory spark plugs at 75,000. These new ones brought engine performance and fuel economy back to what I was expecting. During installation I applied a light coat of anti-seize to the threads, although the factory ones came off easily. I've also used them on an F-150 with about 80,000 miles with the same excellent results with improved idle, power and gas mileage. I have used Autolite spark plugs in various vehicles for decades and they continue to be a high quality product.