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Motor Oil and Filter change intervals...help!

I am so confused about how often to change the oil and filter on my 2009 Hyundai Sonata. It is a V6 and I am getting so many different answers to this question that I don’t know which one to believe. Even the car dealerships don’t agree on the right interval. The manual says under normal conditions, whatever that is, that the recommended mileage/time interval is 7500 miles or 6 months. The dealer says I should do it at 5000 miles or 6 months and then there is the old school theory of every 3000 miles or 3 months. I do use Quaker State Synthetic Blend oil. I only put about 4000 miles every six months and have been tempted just to change my motor oil once a year since I use a synthetic blend and have such low mileage. Is the time interval that crucial? Even though I have only 14000 miles on the car in 2 entire years, it seems a waste to change my oil even at 6 months. It looks like new…meaning the color is the same as when it was changed…the light honey color.

Please help me with this confusion. I would like to know both the mileage and time interval recommendations using a synthetic blend motor oil. Thanks!

Dave

4000 miles every six months is probably severe since most is probably city driving.

You can change once a year. But every 6 months is probably the best and it’s NOT going to break the bank. Even if you take it to the dealer to do the oil change you’re talking about $40 difference. Is $40 going to kill the bank. If it is then you really don’t need a car.

For you the dealer and the manual agree - every 6 months. That’s what I would do.

The guys that wrote the owners’ manual took their information directly from the original design package. They’re the ultimate authority. All other opinions are not from the designers. I always suggest using the “severe use” schedule because oil is cheap and engines are expensive.

5000 or 6 months is my vote

The oil on the dipstick might appear to be a light honey color, but when it is drained it looks BLACK.

If you plan to keep the car for a long time, change the oil every 6 months. I’d change out the filter once per year.

Like the dealer said, 5000 miles is a good number and next owner of your car will thank you greatly for taking such good care of your car for him…

Oil changes are comparatively cheap compared to engine rebuilds…

If you want to do the best you can to take care of your Sonata, change the oil every six months even if you don’t go 4,000 miles. I put less than 6,000 per year on my 2002 Toyota Tundra and change the oil every six months. I figure it’s cheap insurance.

Change it every 6 months and switch to mineral oil. When Hyundai says 7500 miles or 6 months, they mean whichever comes first. There is no need to spend the money for a synthetic blend or synthetic oil unless Hyundai specifically requires it. I doubt that there is any synthetic requirement for your car.

I also have a car that’s not driven much except on longer trips. I don’t worry about the time the oil has been in the crankcase, I change it strictly by mileage every 3K miles and it’s still only averaging an oil change once every 1.5 years. If most of your driving is city/short trips I think you’d probably be safe with anywhere between 3-5K miles, but if it were mine and most driving were city/short trips I’d probably go in the 3-4K mile range. I’d rather spend a few extra dollars on oil and filters than to have sludge problems or damage from contaminated oil. If you really want to get technical when you do an oil change take a sample and send it in for analysis. I think an analysis costs about $20-$30, but will give you an indication of how much life is left in the oil or whether it’s been in for too long. I’ve never done an analysis, but I’ve heard Blackstone Labs is one of the best in this field.

I have no problem with the 5k miles or 6 months recommendation with one exception. That would be if the miles that you drive are accrued a few at a time; 3 here, 6 there, and so on with the car never or seldom seeing extended highway trips. In a case like that you should go with 3k miles or 3 months.

Keep in mind that eyeballing oil on a stick does not reveal very much, many other factors such as environment also factor in, and the use of synthetic oil does not mean it will be less prone to contamination than mineral oil.

If you do a net search about oil sludge problems you may see blame placed elsewhere but it all boils down to one thing; failure to change the oil on a regular enough basis.

The car makers can, and frequently do, make bogus recommendations about maintenance. You can blame some of this on their technical departments and some on the marketing departments; or both.

Yeah I would go 5000 or 6 months but you don’t need synthetic. Isn’t this under warranty though? You will have to follow the owners manual if it is.

Oil diluted with raw fuel or moisture will not look darkened.

I drive ~4000 miles a year.
My Owner’s Manual says change oil every 5000 miles or 6 months.
So I change the (conventional) oil every 6 months.

I think the every 6 months or every 4000 miles idea sounds like a plan.

Friedo82, Bing, I agree ! 5000k Anytime woukd be ok in my book too.

While in powertrain warranty follow manual with time or miles whichever comes first.

Out of warranty do what you are comfortable with which seems once per year.

Your car has a 100,000 mile, 10 year powertrain warranty, if you go over 6 months, you void the warranty. Synthetic or synthetic blends don’t extend the 6 month time or mileage change intervals for warranty purposes.

You drive a low number of miles per year, that put’s the car in the “severe” maintenance category. What is the manual recommendation for severe service?

Uncle turbo, MikeinNH and others…forgive me for disagreeing! It would be boring if we all agreed all the time, but I am struggling to see why light use is " severe" maintenance. If the car sat for a long period, perhaps. It seems the car is getting almost regular but light use. It’s not indicated by OP that use includes any heavy stop and go, short trips, mountainous terrain, dust conditions or trailer towing.

Using public transportation during the week and more car use on the weekends is becoming a norm for many and may not necessarily be heavy use. With that reasoning and with so little snow this year, I would have to change the oil in my tractor, snow blower etc. this spring in addition to last fall. That ain’t going to happen. I have equipment that lasts 40 years as well as friend with antique cars for 60 plus that get their oil changed no more then once a year, if that, with motors in excellent condition. Are we getting into the oil change fetish ? Somehow, we think cars are like people and need to be exercised more often and changing the oil takes care of all our co dependent feelings about car maintenance.

I would be more concerned with moisture accumulation, how stored, gas turnover and rusting in the rust belt. It seems that washing a little more often and keeping it out of the sun would be of more benefit longevity wise. Every 5000 or yearly and six months only if under warranty is more then enough in this situation IMO; and keep track of the local varmint activity. I would love to have a car like this on my shopping list of used cars if in the market. The petroleum industry loves this idea of more frequent, unnecessary oil changes. The environment doesn’t.