I have a 2002 Dodge intrepid that had the oil light flickering at low idle when the engine was hot. I brought it to a mechanic who replaced the switch but the light kept coming on. The mechanic then added an "engine flush" and told me to "cross my fingers" that it works because the 2.7l engine in my car is prone to developing oil sludge.
Now that I have done a little research, I realize that I may have risked additional problems with the quick fix of an engine flush, but assuming that my problem has been fixed temporarily, what is the best course of treatment in the future? Most of the posts I've seen suggest using only synthetic oil in the 2.7l and that will "CUT DOWN" on future accumulation of oil sludge but Auto-Rx recommends not using synethic oil with its product. I would like to use Auto-Rx at least once a year to break down the sludge that has accumpulated and I would also like to use synthetic oil to reduce the amount of sludge that will inevitably be formed in my engine.
Please go to www.auto-rx.com and print out application for heavy sludge. Than go to FAQ and there you will get answer to why no synthetic oil. Whie your reading this post scroll up and read about sludge here on the forum.
For vehicles under 100,000 miles and in good condition a Group III synthetic oil is acceptable for use with Auto-Rx®. Group III synthetic oils include Pennzoil Platinum, Castrol Syntec, and Valvoline Synpower
If you feel that your engine has a significant amount of build up I would recommend doing two treatments. For the short duration oil changes (2,500 clean & 3,000 rinse) conventional oil is just the most economical way to go.
After that there is no need to do an annual ARX cleaning. If you follow up your treatments with an ARX maintenance dose when doing oil changes you should be fine. Use the oil of your choice.
Remember to change out your PCV valve on a regular basis.