There are two options for running Auto-Rx in your 1.8t motor. In light of the fact that your VW service folks have identified sludge as a likely cause of the knocking I am going to suggest running the Fast Track cleaning option. For maximum effectiveness I am suggesting that you run Shell Rotella T, in the 15W40 weight and viscosity. This is the proper weight and viscosity for your motor. Rotella T6 is a group III oil, and is actually designed for diesel motor applications. Which means that it is designed to handle high heat, as well as having a robust dispersant package to help Auto-Rx suspend dissolved deposits.
As part of a fresh oil fill, with a new filter installed, use the entire contents of 2 full bottles of Auto-Rx. Then operate the vehicle as you normally would for 1500 to 2000 miles maximum. Then change out the filter and replace the oil with fresh Rotella T oil only and run this oil change interval out to 3000 miles, maximum as your rinse phase of the application. Then I highly recommend that you run what we call the maintenance dose. The maintenance dose is running ¼ of a bottle, 3 fluid ounces with each oil change. This will help continue the cleansing of the motors internals. You would get 4 maintenance dose out of a single bottle of Auto-Rx.
The sludging issues on these motors is pretty well documented. And it has a lot to do with what VW says is the proper oil change interval, and what it really should be based on driving habits. VW claims a 7500 mile oil change interval. In my estimation that is way to long for these turbo charged motors. After cleansing with Auto-Rx and running a few maintenance doses, 5000 miles would be the maximum mileage I would run a top tier synthetic oil in one of these motors. And that would be if the miles were easy highway miles and accumulated over a short period of time. If you drive in primarily short trip or city stop and go type traffic, then 4000 miles would be my maximum oil change recommendation after cleansing with Auto-Rx.
In summation, run the Fast Track Auto-Rx application with Rotella T6, 5w40. That is both the oil change with ARX installed, and the rinse phase, which is just an oil change interval with no new Auto-Rx added. Then go back to a full synthetic motor oil such as Mobil 1 and use the maintenance dose included for the next 4 oil change intervals, keeping in mind my oil change intervals noted above.
Rich
-- Edited by Frank on Monday 4th of November 2013 03:05:25 PM
