Piston Slap: See the USA in Your K-I-A?

Phil writes:

Hello Sajeev,

I have a question related to maintenance on a 2011 Kia Optima SX Turbo. It currently has 45k miles, and I have owned it for only 4 months (had 20k when I took ownership of it). As you can see, it is driven a whole lot, almost exclusively on the great interstates of the Southeastern US of A. I average 5-6k per month. I am an outside sales rep. and drive from SC to MS and everywhere in between weekly.

My question is this:

Should I follow standard maintenance routines, such as every 5k oil changes and manufacturer’s recommended filter, plug and fluid changes; or can I extend these intervals. If so, how much can these intervals be safely extended? I plan to keep the car for about 3 years or 200k miles if it continues to run as well as it has. Are there any tips to keep the car in top shape mechanically?

Sajeev answers:

The gray area in these situations might as well be the entire discussion: Black and White analysis goes out the window! Some salient points, no matter the vehicle:

• You can kinda, sorta judge oil condition yourself because worn out oil has a different look (not golden), feel in your fingertips (sinks into your fingerprints) and smell (like a BBQ gone bad).
• Turbocharged cars demand more from their motor oil.
• Turbocharged cars with marginal oiling systems (and cooling?) break oil down faster than similar systems. (see VW/Audi engine sludging)
• Many wear items are indifferent to the frequency of driving and driving conditions (highway, vs. city) so you cannot significantly deviate from their service intervals.

In the case of a Turbocharged FWD family sedan with limited real estate for intercoolers/oil coolers/etc, I default to the worst case scenario: a sludge magnet like an older Audi. Stick with 5k oil changes, unless you spend the money for an oil analysis to see exactly how (or at what rate) your driving style breaks down oil. Switching to a full synthetic extends the life of the motor and possibly the service cycle…but I ain’t committin’ to nothin‘ without an oil analysis.

What about other non-engine oil items? Filters, coolant, spark plugs, should be replaced at the same intervals, unless you switch to a K&N air filter…which actually makes sense in your case! The only wildcard for me is the transmission fluid: one person putting that kinda time on the Interstate drastically alleviates stress on your ATF. If three years is all you need, you may never need to change the transmission fluid. BUT…since we aren’t in the business of abusing cars here…assuming there’s no dipstick to check, odds are servicing every 100k-150k is more than adequate.

I hope you enjoy this machine, as the Optima Turbo is on my short list of super cool machines for the average person. I’d love to own one someday, but perhaps you should visit Steve Lang in ATL when you are ready to sell. He’ll make you the best deal when it’s “Hammer Time.”

Send your queries to sajeev@thetruthaboutcars.com. Spare no details and ask for a speedy resolution if you’re in a hurry…but be realistic, and use your make/model specific forums instead of TTAC for more timely advice.