Oil changes... automobile

Kritchlow

Kritchlow

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Kritchlow
Okay, we all know oil changes need to be done on our cars. I also understand some suggest 3,000 5,000 or even more mileage between oil changes.

The question is what about the calendar timeframe?? Does that count?? If it's 5,000 miles or six months, just how important is the six months? Theoretically my car tells me when I need a change, but that could be 10 years as it goes by miles I believe.

I have a C7 Z51 Corvette that takes full synthetic oil.

Thoughts??
 
I still go with 3000 miles (conventional oil), sometimes 4000 if I let it go. My mechanic friend who went to a class or something on oil, says he still goes with 3000. Of course he owns a car repair shop...
 
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We've had my daughter's car for 18 months, and she has put 5000 miles on it. We do her oil changes twice a year because she makes lots of short trips. On the other hand, I have a plug in hybrid that gets driven 13,000 miles a year, and its oil monitor tells me to get the oil changed every 20 months because most of its trips are electric only.

How often do you drive that car, and what are those trips like? Lots of short trips means every six months. Weekend only use? Once a year is plenty.
 
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3000 miles is too frequent on any vehicle. I ran 10,000 miles in my Crown Vic and Explorer on synthetic oil. I always did 5,000 on motorcycles. depends on the oil. I won't go past 5k on conventional oil.
 
I get lots of life out of my engines and I don't follow the Calendar guidelines. I know everybody recommends otherwise but I have too many vehicles, tractors and equipment to be changing oil every six months. So far, I've seen no negative consequences. But I also don't drive a Corvette! I'm driving a 19 year old truck with 170,000 miles and I've never had a single problem out of it. It easily goes 1.5-2 years between oil changes. Which reminds me, it's probably about that time now. When I buy a car I plan on driving it until it dies, and to this point it's never been the engine that goes first.
 
Annually if driven less than 5K mikes per year. I run full synthetic and do 7,500 mi intervals on my F-150 truck, which is the max recommended interval by Ford. I believe it woks out closer to every 5K miles on the Pontiac GXP and the GMC Sierra (both 5.3L V8s), but they also burn almost 2 quarts in between changes (active cylinder management eats oil like crazy). Boat, tractor, and other toys get oil changes once per year. Wix filters for everything with an engine.

Just my own personal timeline.
 
I use full synthetic in every vehicle, and change once a year. They time out before the miles build up. I hate dropping synthetic out that is a year old and only has 2500 miles on it. So I save it and use it in the tractor and lawn mower.

I had a truck in Alaska that used oil so badly I put used airplane oil in it.
 
Just follow your C7 OLM. It takes time into account and will read 0% at the end of a year, regardless of miles.
 
I do 3k or 6mo on my C6, which basically means every 6mo, make sure you have the pucks to jack it up properly.
 
My '08 Ford Escape 2.3, 4 cyl has over 180k miles on it and it's still strong as new, and doesn't burn a drop. Oil changes have been religiously, at 7000 miles.
Valvoline full synthetic.
 
Calendar timeframe: my opinion is it's unimportant if infrequent, low mileage use. Change it out annually, unless you're putting only 100 miles on a classic that you're moving around from home to storage or car shows or not driven at all, then you could go every other year or longer. You're not seeing significant enough use to make a difference to the oil or the engine.
 
1997 Explorer with about 200k miles. Annual oil changes for the past 15 years. Full synthetic oil.
 
It depends on what kind of miles you put on. Highway vs town.

I have a company issued 2013 Ford Explorer. I got it new. I change the oil at 5,000 mile intervals. It now has 261,000 miles on it & runs like new. It's never had a mechanical breakdown. I do have all the other items serviced & had a complete service, plugs, belts, etc at 200,000 miles.

3,000 miles is way too often in most vehicles. This is my opinion....02 worth.
 
2013 Ford Escape with a bit over 77,000 miles on it. It gets an oil change when the monitoring system says it needs one.

1999 Jeep Wrangler with over 191,000 miles on it. At least once a year, only put about 800 miles on it last year (used to be my daily driver).

But, 3,000 miles? It's been decades since I had a vehicle where that made sense (other than the lightly driven Jeep above).
 
Kritchlow said:
Okay, we all know oil changes need to be done on our cars. I also understand some suggest 3,000 5,000 or even more mileage between oil changes.

The question is what about the calendar timeframe?? Does that count?? If it's 5,000 miles or six months, just how important is the six months? Theoretically my car tells me when I need a change, but that could be 10 years as it goes by miles I believe.

I have a C7 Z51 Corvette that takes full synthetic oil.

Thoughts??
Click to expand...

The GM algorithm in your 'Vette is more sophisticated than just an odometer calculation. Unless you lay the car up on jackstands each winter I would follow its determination. If the car is going to sit idle for extended periods I would change the oil and filter just before the mothballing, and reset the computer.
 
Yep, with full synthetic, change it when your car says its time to change it.
 
On a car that's under warranty, I make sure to meet or exceed the manufacturer's recommendations as a starting point.

My 2016 Kia Soul specifies oil changes every 7500 miles or 1 year, but I change it every six months. That comes out to between 5,500 - 6,500 miles. It's easier that way because it avoids having an oil change come up in the dead of winter when it's below zero outside. I also do whatever other scheduled maintenance is coming up, and service all of my seasonal power equipment, on the same days that I change the oil in the car.

I've been using Pennzoil Ultra Platinum for the past few years. The last time I checked it tested in the top three for all characteristics that matter for motor oils, and number one for about a third of them of them. Pennzoil also slaps a 500,000-mile warranty on the engine if you use Ultra exclusively. I know that's just a marketing tool; but for the small cost difference between Ultra and the other oils I like, I may as well take it.

The three tests that I care most about are the wear test (usually the four-ball wear test) because preventing wear is kind of the essence of what engine oil is for; the cold-cranking viscosity test because of where I live; and the NOACK volatility test because my car has a GDI engine. GDI engines are more prone to carbon buildup on the intake valves because there's no fuel wash effect. I figure a low NOACK score probably helps stave that off a bit by reducing the oil vapors in the PCV system. Penn Ultra scores well in all three tests (or at least it did the last time I checked).

Even as an admitted tribology geek, however, I think any of the top-shelf synthetics and most of the mid-range synthetics are excellent. For every characteristic there's a point beyond which the numbers are just numbers. I do enjoy the research, though; and the price difference between "excellent" and "superb" is trivial when it comes to motor oil.

I used to "demote" the used oil from the car to other power equipment, but nowadays I just schlep all the used oil from all the equipment to the county recycling center. I use full-synthetic in the car, but I prefer conventional / synthetic blends in the power equipment. Although Husqvarna approves of either, the full-synthetic seems to result in a lot of lifter noise in the power equipment.

The fact that I no longer demote the used oil is also another reason why I change the oil in all the equipment on the same days. By the time I'm done, I have enough waste oil to make it worth the trip to the recycling center. I used to just drop the oil off at one of the local garages, but they all burn it for heating fuel, and apparently the synthetic doesn't burn well. They still take it because they have to by law, but they're less-than-enthusiastic about it. (The county supposedly recycles it.)

I also keep a maintenance log that meets the diagnostic criteria for OCD. I make an entry pretty much any time I lift the hood or break out a wrench. The log and the scanned receipts help protect me for warranty purposes. They also makes the cars easier to sell or trade in when the time comes. The buyer / dealership manager may look at me like I'm a nut for logging things like "Removed a mouse nest from under the engine cover," but they also know that the car was well-maintained.

Rich
 
Sac Arrow said:
3000 miles is too frequent on any vehicle.
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On any new vehicle, I'd tend to agree. However with older vehicles that didn't have as tight of engines, I disagree. On my 3000GT VR-4 I changed the oil every 3,000 miles, and you could start to tell at 2,500 miles that the oil was getting old.

To the original question, do what the manual recommends. The engineers put a whole lot of effort into figuring out what the appropriate times were for this. Personally I've never paid much attention to calendar time (unless that was just a convenient time to change for other reasons, like my tractors). Reality is in my experience the calendar times don't matter a whole lot on oil in the automotive world because modern engines are very tight and fuel injection helps keep the oil clean. This is also why oil change intervals have stretched out so much.

My cars now (two Mercedes and the Ram) all tell me when the oil needs changed, so I try to change a little ahead of schedule.
 
I RTFM, it tells me when to change. Vehicle one has an OLM, I change when it tells tells me to. Vehicle two the book says every 6k or 6 mo., whichever happens first, and that's what I do on that car. FWIW, our previous car had an OLM that advised oil changes every 13k, and that's what I did. We traded the car at 170k, but not due to any engine issues at all, the suspension what totally shot.
 
Oil threads are fun. Ask 5 different mechanics about oil, you'll get 5 different answers. Ask 5 different drivers and you'll get 10.
 
steingar said:
Oil threads are fun. Ask 5 different mechanics about oil, you'll get 5 different answers. Ask 5 different drivers and you'll get 10.
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Which is why I just say RTFM. Plenty of smart people have determined the best MX schedule for your vehicle.
 
Ted DuPuis said:
On any new vehicle, I'd tend to agree. However with older vehicles that didn't have as tight of engines, I disagree. On my 3000GT VR-4 I changed the oil every 3,000 miles, and you could start to tell at 2,500 miles that the oil was getting old.
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It's a DSM, it's supposed to be noisy and have blue smoke coming out the tailpipes. I actually find it odd when I see any 3000GT, Eclipse, or Talon that doesn't have black soot on the rear bumper/exhaust tips!
 
SoonerAviator said:
It's a DSM, it's supposed to be noisy and have blue smoke coming out the tailpipes. I actually find it odd when I see any 3000GT, Eclipse, or Talon that doesn't have black soot on the rear bumper/exhaust tips!
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I put a lot of effort into making that engine stop smoking. To my surprise, the rings were never the cause of it. Valve seals and PCV valve were the primary ones. Turbos at one point as well. Who knows what that car's doing now, I sold it to a kid who hopefully didn't wreck it or blow it up. It ran LOP nicely.
 
Kritchlow said:
Okay, we all know oil changes need to be done on our cars. I also understand some suggest 3,000 5,000 or even more mileage between oil changes.

The question is what about the calendar timeframe?? Does that count?? If it's 5,000 miles or six months, just how important is the six months? Theoretically my car tells me when I need a change, but that could be 10 years as it goes by miles I believe.

I have a C7 Z51 Corvette that takes full synthetic oil.

Thoughts??
Click to expand...

The rule of thumb with conventional motor oil used to be 3,000 miles for 6 months. The 6 months was really just a simplified estimate because lets so you only put 2,000 miles on your car in town over a 6 month period, just around town and sitting in standstill traffic most of the time, you would need an oil change. Now days with synthetic oil you can go a lot longer, just because the oil takes longer to break down essentially. So the whole time thing was just for people that were not quite as car savy that might need change oil more often than 3,000 miles and not realize it. So to answer your question, the 6 months really isn't very critical, oil doesn't go bad, just gets worn out. And guessing that you have a corvette, it is probably pretty well taken care of, so stick with the mileage limits, maybe just a little sooner than they suggest for good measure.

My 2 cents
 
I have a 2015 Infiniti, 3.7 liter, 300hp V6 that my wife puts less than 10,000 miles/yr on it. I change the oil with synthetic and replace the filter twice a year and although I believe that is overkill, the Service Manager at the dealer (personal friend) says the engine is the weak point on the car and keeping the oil fresh is the best way to keep the engine happy.

That car is quite nice when you put your foot into it!

-Skip
 
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3-4k conventional on older or well worn engines.

Newer/low mileage/still nice and tight engines 5-10k synthetic.

My experience has been once an engine gets older/higher mileage it will start using synthetic oil at a high rate past 4k or so. At that point, to me, there's no point in using expensive synthetic anymore. I just go to conventional and change at 3-4k at that point.
 
Ted DuPuis said:
I put a lot of effort into making that engine stop smoking. To my surprise, the rings were never the cause of it. Valve seals and PCV valve were the primary ones. Turbos at one point as well. Who knows what that car's doing now, I sold it to a kid who hopefully didn't wreck it or blow it up. It ran LOP nicely.
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Yeah, my understanding of DSM folklore was that the valve seals were usually the cause of most of them blowing blue smoke. Our Nissan 300ZXTT never burned a drop of oil, and we ran 10K mile oil change intervals on it with Mobile 1. It amazes me that in the 80's, Nissan could build a nice tight engine that runs for 200K+ and uses no oil . . . but my 2 GM V8's with newer LS-series engines drink 2 quarts in 5K miles, and my F-150 will eat about a quart in 7,500 miles.
 
cowman said:
My experience has been once an engine gets older/higher mileage it will start using synthetic oil at a high rate past 4k or so. At that point, to me, there's no point in using expensive synthetic anymore. I just go to conventional and change at 3-4k at that point.
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My 2004 Honda Pilot is at 234,000 miles. Synthetic since new, changed at about 7,500 miles. Sometimes as much as 9,000, seldom less than 7,300. Engine runs like new. Does not lose a drop of oil between changes.
 
SoonerAviator said:
Yeah, my understanding of DSM folklore was that the valve seals were usually the cause of most of them blowing blue smoke. Our Nissan 300ZXTT never burned a drop of oil, and we ran 10K mile oil change intervals on it with Mobile 1. It amazes me that in the 80's, Nissan could build a nice tight engine that runs for 200K+ and uses no oil . . . but my 2 GM V8's with newer LS-series engines drink 2 quarts in 5K miles, and my F-150 will eat about a quart in 7,500 miles.
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That's a fairly accurate statement. On the VR-4 the PCV valve was another common one. Being boosted, the valve was of a different design (and with different specs) than a standard one. Many people put in aftermarket PCV valves which fit, but weren't designed for a boosted engine. Valve seals were a pain to change, but I got them done. Put way too much work into that car. Some things I miss about it, but ultimately I'm glad it's gone.

GM engines seem to always consume some oil. My wife's Avalanche (5.3) took about a quart between 5,000 mile oil changes, maybe a bit more. Some makers get it right, some don't.
 
‘17 F150 ecoboost. The oil gets changed when the monitor says. The truck ran factory oil and received its first oil change at about 9,000 miles. Motorcraft semi-synthetic with motorcraft filter. I don’t see any reason to get fancy with it.

The f150 Oil change monitor will put a change anywhere between 5 to 10 thousand miles depending on how hard you were working it. At one calendar year it’ll call for a change as well.

The gen2 3.5 ecoboost is a direct injection engine however it also utilizes port injection in certain ways to avoid the dreaded direct injection intake valve issues.

This from the guy who used to run Amsoil in everything. Just a waste of money.
 
When I'm in a really foul mood, I'll punch an old lady, kick a small puppy dog, and start an oil thread on the Internet.
 
Ted DuPuis said:
That's a fairly accurate statement. On the VR-4 the PCV valve was another common one. Being boosted, the valve was of a different design (and with different specs) than a standard one. Many people put in aftermarket PCV valves which fit, but weren't designed for a boosted engine. Valve seals were a pain to change, but I got them done. Put way too much work into that car. Some things I miss about it, but ultimately I'm glad it's gone.

GM engines seem to always consume some oil. My wife's Avalanche (5.3) took about a quart between 5,000 mile oil changes, maybe a bit more. Some makers get it right, some don't.
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I think the cylinder-deactivation models of the 5.3L are what have the primary issues. The older models didn't seem to be so bad, or the models which specifically omitted that technology (6.2L LS3).
 
Sac Arrow said:
When I'm in a really foul mood, I'll punch an old lady, kick a small puppy dog, and start an oil thread on the Internet.
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May as well turn it into a nitpicking grammar thread. You used an extra comma in that post.
 
SoonerAviator said:
I think the cylinder-deactivation models of the 5.3L are what have the primary issues. The older models didn't seem to be so bad, or the models which specifically omitted that technology (6.2L LS3).
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My wife's Avalanche was a 2003 with the 5.3 in it. She'd owned it basically since new, did oil changes on schedule. Burned that quart of oil between oil changes as long as I'd been caring for it (starting at ~120k miles, ending at ~170k). Northstars were notorious for burning oil, too.

Don't know. Honestly burning oil doesn't bother me a ton so long as it's not excessive.
 
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