Simple question. I drive a 1999 (A4) Jetta GL, automatic, with 85,000 miles. It gets regular maintenance, blah blah blah. Between oil changes, when I add the occasional quart, should it be 10W 30, 40, 50? I live in New Jersey – average humidity, no extreme temperatures. Lots of highway driving. …
No web site, no mechanic, no know-it-all brother can give me a straight answer.
Who does your oil changes? They might be a good source.
I’d say the same kind of oil the oil change place puts in is a good bet regardless of what kind of car it is. If the windshield sticker doesn’t say, if you still have the invoice from your last change, it should indicate what grade they used.
Does your car have an owner’s manual? What did it say?
I wouldn’t mix weights…Find out what they put in during the change &use that. What if they put in synethetic oil & you put in regular oil?
OK. I’ll bite.
What happens?
Not much, in either case. While you lose the advantages of synthetic oil if you mix Dino oil in it, it wont hurt anything really.
Everybody DIES!
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The answer will be on the fill cover of your engine. It will also be on a metal plate between the hood of your car, and the frame. This metal plate will be riveted on. It will also be in your manual.
Use Castrol Syntec oil, and I’m guessing it will tell you to put in 5w30 oil
I would think 5w30 would be good for New Jersey b/c it’s viscosity is more suited for colder temperatures.
Hey, great stuff. Thank you. I’ll check for the metal plate, Scylla.
The driver’s manual contains NO mention of oil grade. (Plenty of warnings to fasten the seatbelts, though. Plenty of warnings to apply the emergency brake when parked.) When I get the oil changed, I’ve seen a variety of grades on the service order. I’ve been told it varies with the time of year, the mileage on the engine, and the mechanic’s ‘‘preference.’’ Sigh. Dad shuffles off to that great garage in the sky and takes all these secrets with him.