Oil Change Interval

cleaver

Veteran Member
Joined
May 8, 2006
Location
Berwick, Nova Scotia
TDI
None - did own '01 and '02 Jetta TDI
Hello all,


Why does car manufacturer's require oil changes based on time. I understand a 5,000/10,000/25,000 mileage oil change but why would you need an oil change every 12 months if you only drive half the required mileage?

Does oil go bad once its opened? If you do an oil change and then store the car for 5 years without driving it, do you need to do another oil change before you drive it? why or why not?
 

oilhammer

Certified Volkswagen Nut & Vendor
Joined
Dec 11, 2001
Location
outside St Louis (where it's safe)
TDI
There are just too many to list....
I think they assume you are maybe doing shorter trips, which can be more detrimental to the lubricants. Some newer cars however take this into consideration, and use a sophisticated algorithm to determine when service is required.

My Sprinter, which does NOT have the flexible interval minder (ASSYST), and just has a fixed 20,000 mile or 24 month, recently had its service reminder come on. I do not even have 10k miles on it quite yet, but it is 24 months out of the factory. Since 95% of its driven miles have been cruising down the highway, I am not all that concerned about the time. But the onboard system in mine does not keep track of that sort of thing. The ASSYST equipped ones do. Similar to many GM vehicles.

We have some GM fleet vehicles that do lots of highway driving, piled on pretty quickly, that will come in here for service at 5k miles (because that is what the dumbass fleet management people want :rolleyes: ) and they will still show 65% remaining oil service life, and on the non-turbo portinjected ones, the oil will generally still look fine and still be within the operational range. Of course, that crappy little 1.4L turbo they have will be 2 quarts low and full of black burnt tar water after 5k miles.

But in the end, they are probably just wanting to be sure the hood actually gets opened (where applicable) and the oil gets checked. You'd be surprised how many people cannot do that. I check the oil of every car that comes through our door (save for the few EVs) and you'd be shocked how many are low. EVERY Subaru that comes in here is low... no matter if they are due for service or not. And we service a fleet of those turds that are all 2015+, and they cannot go more than about 2500 miles before the oil level is below the operational range on the dipstick. They've already blown up a few.

FWIW, I have quite a few cars, and I still go by miles no matter what. The only exception will be the Sprinter, as I will change its factory fill at 10k miles instead of 20k, which will have it likely around 27 months from its build date. If I were driving it more I'd go the full 20k. I change my F150's oil every 5k miles, which can be about once every year or so, as I do not drive it all that much.

I would say just keep an eye on the oil level and use your best judgement. If you rarely drive a car, but when you do it is just a short trip, you may want to change it more frequently. We are seeing more of an oil dilution problem with DI gassers like we did back with carburetted engines, especially in cold weather and short trips.
 

cleaver

Veteran Member
Joined
May 8, 2006
Location
Berwick, Nova Scotia
TDI
None - did own '01 and '02 Jetta TDI
Thanks for the response. It was a more philosophical question than anything at my workplace. My two vehicles (Jeep/Hyundai) get more km than most vehicles out there. My Sonata '11 drinks oil like I drink rye, but it still runs great. (about a quart every 1500 miles if driven hard, a quart every 2500 miles if eco driven) - which reminds me that I have to go add a quart.
 

oilhammer

Certified Volkswagen Nut & Vendor
Joined
Dec 11, 2001
Location
outside St Louis (where it's safe)
TDI
There are just too many to list....
Your Sonata has Hyundai's version of the World Engine, and they love to blow up... usually because they are run without oil due to the consumption issue, but not always. We get them in here with rods falling off for no good reason.

A lot of those were under a warranty extension, but they didn't really "fix" anything. The Sonata/Optima is the worst, but we'll see it on the Santa Fe/Sorento and others as well.

Really sucks, because the car is decent enough. Drive nice, roomy, etc. My cousin has a Forte that is on engine #3 and it has not even hit 100k miles.

The newer version of that engine has a bunch of revisions, but one of the "improvements" is they made the VVT actuator gear electric controlled oil driven complexity. And oil seeps into the electric part and fails, and results in a wallet emptying affair to fix. I forget when they went to that, but it was recent, maybe 2015+.

But google recall campaign 132, as we've sent a lot of the blown up HMC cars to the dealer for a free engine on their dime. Even if it is still running, they will inspect it and see if the rods are going to fall off.

The extension is number TXX3, different checks, and covers more years.

May be different for Canada, but probably not.
 

cleaver

Veteran Member
Joined
May 8, 2006
Location
Berwick, Nova Scotia
TDI
None - did own '01 and '02 Jetta TDI
thanks for the info.

I like the Sonata but the oil consumption has me a little worried as well as the recall. The car drives well for what it is. Took a trip to Missouri (Elsberry) and back to pick up a new puppy this spring and had to add oil almost every night... (1100km a day, 7300km in a week).

any ideas on reducing oil consumption or why its consuming so much oil - it just started about a year ago.
 
Last edited:

oilhammer

Certified Volkswagen Nut & Vendor
Joined
Dec 11, 2001
Location
outside St Louis (where it's safe)
TDI
There are just too many to list....
They really do not disclose much info to be honest. I would seriously contact your local dealer and see what they have to say. They may replace the engine for you.
 
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