Synthetic blend/conventional oil

And I read yrs ago if the car is old and you use synthetic that could cause a leak.

Urban legend…total cr*p.

Not so. On my older cars, every time I tried synthetic, out of curiosity, the oil senders started leaking profusely. I am talking 70’s era American cars. The newer ones did not.

Here we go again with the false statement that synthetic serves no purpose in ordinary driving. I have been following that nonsense for some time. A few months ago, the last time someone pontificated like that, I spent a great amount of time searching the Internet. Except for one man, who also believes extra-terrestrials are on the planet, universally both professional and shade-tree mechanics agreed it is extremely rare to get sludge while using synthetic. Considering how often we hear of sludged engines, I would say that precludes no benefit from synthetic.

It is also interesting to observe how many people say to change oil much more often than recommended, with the argument that for the little extra cost, it is nothing compared to the cost of a motor. But, the minute we mention synthetic oil, omigosh, you will be bankrupted with the extra cost, don’t do it.

Op, here is a link to a certified oil expert, on page 2, Jotmo,on how often to change oil, which is closely related to this topic.

http://community.cartalk.com/discussion/2279373/oil-change-every-10000-miles/p2

He knows what he is talking about, and explains it for you.

irlandes; I’ve used synthetic, semi-synthetic as well as high quality mineral oil. They alll have their place. Our winters here are severe, and a 0W30 synthetic allows very cold starts and also provides excelent film strength for the bearings. The summers here are very moderate, so I often use a good quality mineral oil then. When towing a trailer in the past I would use a proper grade synthetic.

If I was in your shoes, in Mexico with hot summer weather and dusty roads., I would use synthetic exclusively.

In the past we discussed having oil analyzed to see how it stood up over the miles. I did this with a carbureted 305 V8 Chevy, and after 2000 miles, the oil was virtually in “new” condition. At 5000 miles there was carbon in it (not excessive) and some additive depletion. In the winter I used 0W30 synthetic to ensure good cold starting. after 3000 miles, the metal count in the oil was only 55 parts per million (ppm) (EXXON condems oil at 200 ppm). GM that year specified 3000 mile oil change intervals or every 3 months. I followed this, but could have stretched it further without ill effect since the car was always on paved roads, parked inside, and used a block heater in very cold weather.

This car was disposed of when it was 22 years old and had 320,000 miles on it. The compression was right up on 6 of the cylinders and at 95% on the remaining 2. The car used 1 quart of oil every 2000 miles, but that was mainly due to small leaks at the bottom of the engine.

Your 8800 miles between changes in Mexico is remarkable, but it is a classic application for synthetic oil with great heat resistance and film strength.

This panel basically has no great disagreement; changing oil frequently enough (but not more) and using the right oil gets us long and trouble-free engine life. I have owned cars since 1958, long before we could buy synthetic, and have never scrapped one because of engine failure or wearout.

We all agree that analyzing the condition of the oil is a good way to learn what actually happens to it. Taxi and truck fleet owners do this routinely and arrive at the most economcal interval for their operation.

I still don’t go for the extended oil changes with synthetic oil. My BIL swears by Amsoil and used the 20,000 mile Amsoil filter, and his engine is a mess! Looking into the oil fill hole I can see varnish and crud built up on the valve springs and everything else. When he pulled the dipstick I could also see a nice coating of unremovable crud on it, too. My Odyssey has 130,000 miles on it using Valvoline or Castrol dino oil (whichever is cheaper that month at Walton’s). I change the oil and filter about every 5,000 miles and the engine is quite clean, run perfectly, and burn/leaks no oil. I pour 5 quarts in and 5,000 miles later I drain 5 quarts out. Maybe Mobile 1 is a much better product than Amsoil, but from what I’ve seen of Amsoil with 15,000 mile changes…I’m not sold at all. For about $15 I can change my oil in half an hour without even getting dirty. Engine replacements are a bit more involved than that.

doubleclutch; you are proving that a little common sense goes a long way. Your BIL, on the other hand is falling for the AMSOL hype, and will have a very short-lived engine. Your Odessey does not specify synthetic, and unless you use it under extreme conditions, normal mineral oil of the correct viscosity will do the job.

AMSOL does not fully meet the most stringent API specs or the European specs for that matter. The extended drain Mobil 1 meets the tough European standards, and could go 15,000 miles under normal driving conditions. Having said that, no owner’s manual for US built cars will let you go 15,000 miles between oil changes.

There is a shop here in my neighborhood that pushes AMSOL, and the guy who sells the stuff draws a blank when you push him on the API specs.

Your BIL needs an education on the difference between real quality and hype. Mobil 1 is an acknowledged high quality synthetic and it lists all the standards it meets right on the bottle label. But even the best Mobil 1 only says that it is good for no more 15,000 miles.

A Kirby vacuum cleaner, sold by high pressure, high commision door to door salesmen is a good vacuum, but at $1500 it is definitely not 6 times as good as a $250 unit, and it will not last 6 times as long.

I too agree that doubleclutch is using good common sense. It’s unfortunate that his BIL has fallen for the hype he has, but perhaps one day he’ll become more aware. In the meantime, he’s part of a very, very large “club”. Billions upon billions are spent on magic weight loss things, magic beautifiers, things that add “more power plus improved mileage”, and countless other hype by good people simply hoping for some magic.

Now, about those extra-terrestrials…

Thanks for the compliments, guys! I do keep a bottle of 5W-30 or 10W-30 Mobile 1 around the house for household use. I oil my hair clippers and my numerous pistols and revolvers with it. Our cars get driven enough (no short trips, etc…) that they keep the dino oil in pretty good shape.