got 1125,000 miles, never had an engine oil flush. has anyone had a bad experience doing this?

 

Your question may come down to personal preference/opinion but my stance has always been that an engine flush is a bad idea on high-mileage vehicles. Reason is, that sludge you are removing often time is the only thing coating and protecting old worn out seals and gaskets. I've heard numerous stories of people getting their engine flushed only to experience oil leaks shortly after. My 2.3L ranger has never had a flush of any kind, now has 208,000 miles, and still runs great with NO leaks. Again though, that's my opinoin, and I too would be interested to hear what other more experienced folks think.

 

You can think that sludge in there is protecting the engine if you want. If it makes you feel warm and fuzzy inside to belive that, go right ahead.

Lets get to the facts.

•Sludge is bad. It does not protect or seal you engine. You don't want sludge.
•If you have sludge, you might have bigger problems to worry about. Use a slow gentle cleaning additive and switch to a higher quality oil.
•The life of the gaskets has a lot to do with the maintenance history and quality of the oil. Low quality oils tend to contaminate faster. This causes the anti-oxidation additives in the oil to break down and when they do, any rubber seals the oil comes in contact with start to dry and harden. Again, use a higher quality oil.
•Get the engine up to full operating temperature. If most of your driving involves trips that are less than 30 minutes long, the oil tends to break down and contaminate faster. If your regular driving does not give adequate time to heat up, plan on taking a long drive for at least an hour about once a month. It helps "boil" off the volatiles that get in your oil, and not only helps protect and condition the seals, it helps the whole motor last longer.

A good aditive if you are concerned about sludge is a product called AutoRX. It is a slow acting detergent additive you put in the oil. It will slowly clean away any sludge and help condition the seals. You then drain the oil to get rid of the contaminants that it dissolved. Other products like Seafoam and BG44K are too fast acting in my opinion, detergents and solvents in such high concentrations can compromise lubrication, and can dislodge sludge and allow it to get trapped in passageways. I have never experienced this, but I have heard of people having bad experiences with things like lifter wear and ticking noises after using a strong cleaner in the oil.

The oils I use are so good at cleaning the engine, for me it would be pointless to even consider adding anything extra to the oil to clean the engine.