Oil Changes

I use synthetic in everything including my lawnmower. I run synth in axles, trannies and grease fittings. I’ve run it in 4 race cars (I build my own engines) with amazing results. Street cars get 10,000 mile oil changes instead of 5000 thus removing the cost penalty compared to premium dino oil and filter. Not only does my oil stay so clean its hard to read the dipstick 2000 miles later, it is worth 1/2 mpg in every car. The gear lube in my 4WD adds another 1/2 mpg (and yes, I’m OCD enough to keep long term records). I use it because it is better, in all respects. Check out www.bobistheoilguy.com if you want the full story in excruciating detail!

@jtsanders
I think I was not clear. What I mean is, this is the same train of thought that brake companies use when they put a lifetime warranty on there parts. They know the part will wareout eventually. However so few people actually take advantage of this, that the cost benefit of offering the warranty pays for it self. The oil is the same way, so few people will say anything when there motors blow (at high miles which the mitor probably would have done anyway) that the advertising advantage more then makes up for the cost of repairs.

@mechaniker
The problem is those same BMWs (and minis by the way), are turning 100+k and are dieing due to sludge bulid up. Since they are out of warranty, it’s tough luck On the owners. BMW is washing there hands of it. We see posts on here every now and again of people who followed the 15k oil change schedule and now have very expensive paper weights.

Just because the oil can last that long does not mean it should.

"Street cars get 10,000 mile oil changes instead of 5000 "

But how do you KNOW this? I mean, did you test the oils? Might the regular oil have lasted longer?

texases “How do you KNOW this?”

Remember the Mobil 1 commercial cooking regular oil in a frying pan next to Mobil 1? Regular turns to coke/sludge and the M1 is fine. Pretty convincing to me. My last race car ran very hot, 300 F oil and 235 water were common. There was NO sludge, coke or bearing issues. Reinforced my use of synthetics.

I don’t test the oil at changes. The street cars get documented better mileage thus proving the better lubricity, history shows me they stay cleaner. The cost of oil changes is $1000 over 200,000 figuring 20 changes at $50 a change. Less than the machine shop bill for a rebuild.

Also, if one of the street cars has an issue with the oil or cooling system, those events may destroy an engine with a lessor oil. Cheap insurance.

That said, dino oil these days is very good but the extra cost of synthetic is worth it.

Oil temp. In a passenger car usually runs around 210-220 F in the sump. Driving like a blithering maniac can take it up to 260, but it is questionable that a Corolla would burn enough gas to do this. Tests like putting oil in a frying pan and heating it to 300 F are marketing/advertising tactics derived by people who went to college to learn how to bull#%&$ people into thinking they need a product whether they need it or not. Street cars and racing cars are very different beasts. Nobody is gonna notice any real difference using synthetic in a Corolla, and as I’ve said on this site before, I know people who use synthetic with 15,000 mile oil changes, and their engines are a mess!

Synthetic oil may be better grade oil I don’t know since I’ve never used it, but if the car is properly maintained with oil changes every 5K miles the engine will probably last as long as you’ll want to drive the car. I’ve got an '88 Ford Escort that’s never had anything other than conventional oil used in it, it currently has 518,700 miles on it and is still running although it is now using a significant amount of oil (qrt every 800-1K miles). I use to drive it about 35-45K miles per year driving it back and forth to work on construction sites 5-6 days a week at speeds of 80-90 mph on the interstate on 90-100 degree days when it had in excess of 300K miles. I’ve ran other cars in excess of 200K miles on conventional oil without problems. I currently own 2 other cars that are near 200K miles that run fine and use about 1/2 quart of oil between 5K mile changes. 2 other cars between 100-150K miles and use no oil and 2 cars with under 100K miles that use no oil. Even if I used synthetic oil I wouldn’t feel comfortable increasing the change interval to 8-10K miles like many people do, because I’ve seen the effects of oil sludge on an engine. I’m not trying to convince you to use conventional oil, it’s your decision I was just giving you an example of my service history using conventional oil.

A turbo charger is a particularly difficult situation because most drivers refuse to allow the turbine to slow down before shutting off the engine. When the engine is shut off oil pressure immediately drops to zero and if the throttle has been recently blipped the turbo charger may be spinning at 10s of thousands of rpm while it is very hot. That situation flashes the oil off to ashes which don’t lubricate very well. Synthetic oil is has a much higher flash point and will significantly improve the longevity of a turbo charger. If drivers habitually let their engines idle for about a minute before shutting them down mineral oil would likely work fine. The instructions manual on a military multi-fueler spells it out quite plainly.

I agree with your points doubleclutch. The only caveat I’d add is that people check their manuals. Manufacturers now are beginning to use turbochargers on even economy car engines to get the most out of them while keeping their CAFE numbers below the “fine level”, and even on an econobox turbos run at high speeds, heated by hot exhaust, and their bearings lubed with the engine’s oil.

I agree with that one, Mountainbike. Turbochargers can spin well over 100,000 RPM and the turbine side can get real hot. I’m not an expert on all the systems in place, but I would hope that there is some coolant flow around the bearing area, and I’d imagine that the lube system POURS oil through the turbo bearings. Even so, I’m sure it is a good idea to let the turbo spin down and cool awhile before shutting the engine down. My point is that the virtues of synthetic oil extolled in advertisements deal with conditions that most passenger cars will never even come close to replicating. I use Valvoline or Castrol dino oil because one of them is usually on sale at Wal-Mart, and I change it every 4 or 5 thousand miles and my engines are quite clean and use NO oil.

I would bet that in the not-too-distant future, the most common oil on the shelves at auto parts stores, discount stores and farm stores will be synthetic oil. I remember when detergent oils came along. In about five years, the detergent oil displaced the non-detergent oil on the shelves. It took about the same time for multi-viscosity oil gain prominent shelf space over straight weight oil. I’m betting that we will see the synthetic oil become the most popular oil rather soon.

+1 @Triedaq - small turbo engines are becoming the rule, rather than the exception, and they typically use synthetic. Didn’t GM recently come out with a new oil spec for sythetic. Some oddball name.

I would expect also that the price will come down to a level comparable with dino oils.

But one never knows. Many years ago most cars took 5 quarts of oil and oil was only sold in 1 quart containers. Now they take 4 quarts…but oil is sold in 5 quart containers! Go figure.

I live in an area that gets VERY cold in the winter. While I am unsure of what benefits I get in the summer from my synthetic oil I can tell you for sure that winter starts at zero (or below) are MUCH easier with synthetic oil than with dino. I do a ton of long highway miles so I use synthetic for peace of mind when going 8,000 miles between oil changes. I am pretty sure dino would work as well but the synthetic is cheap insurance. On sale my synthetic is only five to seven dollars more per oil change.

What kind of synthetic do you use?

Here in Pittsburgh, it rarely goes below about 10 F. On the occasions that it has gone below zero, My car started OK, I just keep the RPM down and drive gently for the first few minutes 'till it starts to warm a bit.

Will synthetic oil enabless engine friction and therefore increase fuel mileage?

Nope.

I have a 2012 Toyota Camry and the owners manual calls for synthetic oil SAE OW-20 every 10,000 miles or equivalent. In my other cars I always used Mobil 1 after one of the engines were torn down and I saw all the sludge from regular oil blocking the oil ports. The cars using Mobil 1 gave me service for 250,000 miles with no engine problem at all. Did I notice any driving difference? No. I used it to extend the life of the engine. I drive my cars for a long long time.

All I can add is my own experience with the 1972 Volkswagen Super Beetle that I owned and drove for 35 years. I used 30w Pennzoil for all those years and changed the oil every 3000 miles. I donated it to charity when the gas tank began to leak, the (front) trunk could no longer open and I started getting 2 to 3 inches of rain inside the car every time it rained.

I decided then that I didn’t want to spend money on a 35 year old car to fix all of that stuff and instead bought a 2007 Yaris, which has been trouble free, by the way.

My point is that the engine still ran great when I donated the car. I believe that if I had used synthetic oil for those 35 years (was it available in the early 70’s?) it would have made absolutely no difference in the quality of my VW engine’s performance.

What does this prove?

It proves (to me, at least) that following the auto maker’s maintenance schedule will get you maximum performance from your engine - and using a synthetic oil that is not required or recommended is not necessarily going to give your vehicle’s engine a longer life.

Not a scientific and controlled study but good enough for me.

I tried 0W-30 synth last winter in my 2006 Matrix instead of 5W-30.
Didn’t sound or run different that I could tell.
Any MPG difference was < 1MPG.

the synthetic stuff is more expensive than the natural stuff, but you don’t necissarily have to change it as often. the bottle says that it can go anywhere from 10,000 to 15,000 miles between changes, but i do a lot of city driving and therefore tend to still get it changed at most every 5,000 miles. i myself use the synthetic oil in my '98 bmw 528 and it runs like a top, though i must say i have never tried the natural oil in this car.