This is a highway-only car with 138K miles. I’ve changed the oil at 10K intervals. Went to get a change today and the mechanic made a big push about dirty oil and wanted to “flush it out.” I’m sure you guys have dealt with this before but I haven’t been paying attention. Is a flush really necessary?
Only the mechanic really knows. He may have seen some sludge or something this time. If you haven’t put additives in your oil I don’t know why it would need flushed with that many miles, but I didn’t see what came out of it.
Was this a dealership, independent, or a quickie lube type place?
Take a look at the area under the oil filler cap. May need a flashlight and mirror - or remove the valve cover. Any deposits there? Thin baked-on black is OK. Anything thick or jelly-like is a cause for concern. I question what a “flush” will do, however. If the oil drain holes are getting filled, for example, pipe cleaners or the like are the way to go.
Miles or KM? Synthetic or conventional oil?
Doesn’t Hyundai specify 7500 miles max for this car?
Doesn’t this have a GDI engine? Those add more soot to the oil.
10K mile changes might indeed have left your engine dirty.
I wouldn’t flush. Just do a couple short changes, like 3000 miles.
I have a 2017 Tucson with GDI, and I will be changing with synth oil every 5000 miles.
You are right to be skeptical. I had a chain shop one time recommend this procedure on a seeming whim; I didn’t do it, and it wasn’t needed. But your car could well need this done; especially if your engine sports variable valve timing and you’ve gone the full 10K miles before oil and filter changes. That’s too many miles imo. Remember that all car manufacturers have a conflict of interest: they want you to be satisfied with your current car, but they are also in business to sell new cars. The longer you are satisfied with your current car, the longer they have to wait for you to buy another new one. The same is true of repair shops, especially chain shops. They’ve invested in an oil flushing machine and if it just sits there unused, it isn’t generating any revenue. That’s another conflict of interest.
The only way to know for sure is to have your engine evaluated by an independent mechanic who has a lot of experience w/Hyundais and no particular reason to recommend an un-needed oil flushing procedure. Ask friends & relatives who they use for car repair, and from that list choose an inde shop with Hyundai experience.
Of course if you can clearly see a significant amount of oil sludge looking through the oil fill cap into the valve area, this definitely requires the evaluation of a specialist. Ask them to remove the valve cover for a better look if necessary.