Owners of these 1.8T motors are common customers here at Auto-RX. Unfortunately many have run closer to 8000-9000 mile oil change intervals and have oil circulation issues, such as blocked drain holes in the head and clogged oil pick up screens. You are smart running 5000 mile maximum OCI's.
For best results, I would suggest running your cleaning application with a group III oil, such as Pennsoil Platenum or Castrol Syntec, just to name a couple. Group IV(PAO based) oils have esters added to the base to couple additives into the PAO base. It is best to run Auto-Rx with an oil that does not contain any significant level of coupling esters, therefore we recommend group III for engine cleaning.
Are your wear numbers creeping up across the board? Or just soft metal bearing/bushing wear? Any fuel dilution issues?
We have found in virtually every case that by running the maintenance dose, which is merely an addition of 3 fluid ounces with each oil change, we can lower wear rates. This is used after the initial cleaning and rinse. The maintenance dose can be run with any oil, group III or IV. What you may not know is that the cleaning esters in Auto-Rx are excellent lubricants in their own right. Beyond its cleaning ability ARX will improve oil film strength, increase the extreme pressure capability of the oil, prevent any type of corrosion, acts like an acid scavernger.
Anything that I didn't address, please reply back.
