Every 5000 miles-ish.
Were I in your shoes, I would change the oil before I left.
It has one quality that may justify its (seasonal) use: viscosity at very low temperatures (say, -20F and below). When it’s that cold, an engine with synthetic oil will be much easier to start.
It truly depends on what kind of car you have and what kind of driving conditions it is under.
Older model or newer?
High performance or economy car?
City or highway driving?
Ever drive on dusty dirt trails?
Do you spend a lot of time idling?
Even how much you start your engine and how hot it runs will be a factor.
My dad is a mechanic and I have been around cars my whole life. I currently work for a dealership. In older model cars 3000 miles is a good guideline. In newer models, the service interval is longer. My current car’s recommended interval is 5000 miles, but it also has an oil change sensor that monitors my driving habits and conditions. My light might not come on till 8000 miles. I still get my oil changed between 3-5000 miles.
I’ve seen what happens to engines when the owner neglects to perform routine preventative maintenance. It is much cheaper to change your oil regularly than to replace an engine or a car. Pretty much across all brands, if you take care of your car, it will take care of you.
Might I add that if you do not follow your manufacturer’s service interval guidelines and you have a repair issue that should be covered under warranty, you will likely have trouble getting your warranty honored.
I’ve read used oil analyses from cars run on the high side of 20,000 miles on a single oil change with quality oils. Some of these analyses did in fact look much like what a 5,000 mile change would look like with a different oil… the difference being that the additive levels were trending towards depletion.
Actually, on a “iron/copper/aluminum wear particles per 1000 miles” basis, most of the high-mileage changes averaged out better than the 3000 mile changes; apparently for the first 700 miles or so on new oil your car experiences exaggerated wear due to the additives in the oil not being heat activated or something.
Incidentally, since the OP is planning a road trip with older oil in, he should bring a couple of quarts for top-off. It is quite possible that the extended drive will “refine out” some substances currently in his oil and result in his fluid level dropping by a quart or so during the first half-day of the trip.
The first part of your post, wherein you advise home-mixing of synthetic blend motor oils is misguided. You are likely to wind up throwing off the carefully engineered balance of the oil as much as you enhance it when you do that. There are a half-dozen common theories of additive formulation, any one of which may be in use in your conventional motor oil and synthetic motor oi, intended to be balanced carefully to match the needs of the base oill. It is possible, actually probable, that you’ll wind up diluting the active additive in one oil while introducing a sub-therapeutic dosage of a second additive to the overall mix.
I’m not saying that mixing brands with top-off fluids is evil, but you aren’t doing yourself any favors intentionally mixing oils.
Some oils rely on additive doping while others rely more heavily on expensive base oils, and trying to second-guess professional tribologists is an amusing hobby but not likely a terribly effective one.
Incidentally, if I were to look at a given line of road-vehicle oils, I’d likely find that, let’s say, Exxon-Mobil has 5-7 different theories of formulation in play:
- Conventional 5W20 usually gets a unique formula.
- Conventional 5W30 through 10W40 gets a second formula.
- Straight 30 weight and 15W40 get a third [diesel-oriented] formula.
- Synthetic 5W20 gets a fourth formula.
- Synthetic 5W30, 10W30 and 0W40 get a 5th formula, oriented towards gas engines.
- Synthetic 5W40 gets a 6th diesel-oriented formula.
etc…
Notice I didn’t touch on their synthetic blends, or the Esso/Exxon Canadian 0W30 and 0W40 blends, the aviation oils and their series of marine diesel oils.
Bottom line, fill it up if it’s low with anything suitable, but if it uses oil, buy an extra quart at oil change time for top-off.
If you’re buying oil that doesn’t suit your needs, don’t dope it! Buy the right one to begin with.
Oh yeah, and regarding the second part, with the exception of temps below -25 F or so, cars that mandate synthetic oil in the owner’s manual and turbo-charged gas engine cars that SHOULD have mandated synthetic, you’re dead-on right. Waste of money and all.
I change mine about twice as long as the jiffy-quik-lube tells me. If they say return in 3000 miles, I’ll be in at 5-6k.
Of course, as it turns out, my car gets totaled every 5 years by another driver. So balls to proper car care.
I add 4,500 to the sticker on the windshield…
So, around 7,500 or so.
2002 Hyundai Elantra, thrashed to within an inch of its life since the day the odometer crossed 5k and I decided it was officially broken in.
I try to to go 6,000 miles at most between changes, but I’ve gone as many as 11,000. And I NEVER use synthetic (The one time I did, my fuel efficiency dropped noticeably, and kickdown took longer- the latter might be my imagination).
Consumer reports did a test a while back. They took 20 new NYC taxicabs. They changed the oil on 10 of them every 5000 miles, on the other 10, every 10,000 miles. At the end of 100,000 miles, they tore down the engines. Even under a microscope, no differences were apparent. Jiffy Lube is definitely lying to you when they claim 3000 miles.
In my 2005 Mini Cooper, the odometer tells me when it needs to go it. When I start the car it gives me the mileage left until the next service appointment. It adjusts itself depending on how it is driven, but it was ~10,000 miles to the first change, and my next isn’t until ~25,000 miles.
Once every 6 months. I drop the car off twice a year for a service and a grease and oil change. So probably about 8,000 miles.
As for the Consumer Reports test surely they are kidding if they think the wear and tear on an average car has anything to do with the wear and tear on a NYC taxi cab. I recall in high school one of my friends bought a cab with nearly 250,000 miles on it, and because it was running all day most days it was in far better condition than the average car driven by a suburban mom that did little 5 or 10 minute drives.
Yes, the wear and tear on a NYC taxi cab would be worse than an average car. Stop and go and idiling all day stresses a car more than normal driving. Cars are most efficient at a constant speed, like on highway. Look in your owner’s manual, it should mention a “Severe duty” maintainence schedule for taxis and emergency vehicles.
I get mine changed every 3750 miles as recommended (OK, it slips by a few hundred but it’s usually pretty close). Jiffy Lube does it on the “off” mileages when I don’t have a more major service and the dealer does it at part of the others.
It’s an eight-year-old Civic but I’ve followed the 3750 mile thing from jump. Plus whatever that super-early one was when you first get the car. I drive mostly country with few stops, and a few long-distance trips.
Well I have never heard of “severe duty maintainance” but I don’t see how “stop and go and idiling” applies to taxis, at least in Sydney. They are constantly working and usually remain at optimum running temperatures all day, every day.
Well, for some vehicles, the severe service interval is indeed 3000 miles. I have a 2005 Dodge Dakota with the 3.7L v6, and my severe service interval is 3000 miles, with the “normal” service interval at 6000.
The perplexing part is that right there, next to the description of what constitutes “severe” and “normal” is a sentence stating that the majority of owners will fall under the “severe” category.
Anyway, I’m changing at 3000 until the warranty period has expired, and at that point, I’ll probably go to the 6000 interval with something like Pennzoil Platinum or Valvoline Durablend. I’ve had really good results with the 5-6k interval and synthetic oils (I got 198,000 out of a 3 liter Ford Ranger engine with 5000 mile Mobil 1 changes; no smoke, no consumption, no problems at the end of that period!)
If you really want to learn about oil change intervals & different kinds of oils, etc… go to the “Bob is the Oil Guy” forums and check them out. (you can google “Bob is the oil guy” to find them)
I generally go between 5K and 7K between changes, and alternate them between Jiffy-Lube and my school’s auto shop. I drive a Nissan Frontier, and put 250,000+ miles on the last one before trading it in.
Driving in NYC involves a lot of red lights, flooring the accelerator pedal, merging, fast braking, potholes, being stuck in traffic jams, and cursing.
BMW- 6k. Comes out as clean as it went in.
Nissan- Around 5k, or when I get to it.
Big Ford- Once a year, before the big trip. Works out to about 3k.
Fiat- Every year or so. Sometimes two. Never drive it enough. I should drive it more. It gets great milage and is a blast.
Old Ford, Jeeps, Volvo, motorcycles, etc- Never, or when I have nothing better to do. Don’t drive them enough.
Now I feel bad. 