Soaring

Yes, because the gaskets have dried somewhat, and they tend to leak the synthetic oil. But, after several miles, they tend to quit leaking. But, there will most likely be a mess under the car that will need to be steam cleaned. Which brings up a point. Do you start using synthetic with an old engine or not? I wouldn't if it is only driven a few miles a year. But, if you overhaul the engine, then that is an opportune time to start using the synthetics.

jrrhd73must

Here is my experience. I have been selling Amsoil as a dealer for 3 years now.

I had a 93 Honda Accord with 186k on it. I switched it to Amsoil as an experiment. It leaked. The old gaskets tend to crack and dino oil will seal them with the waxes and impurities. When you switch to synthetic it has a lot more detergents and will clean out all of the junk and older cars tend to leak. After about 5k or so, the conditioners in the synthetics treat the seals and they swell and tend to stop or leak less. Back to my Honda, it pretty much quit leaking. At 206k it started over heating. I stopped at a garage, since I finally found the leak and wanted to buy a hose. He told me that the car was toast becuase the Honda's heads will warp under the heat. The compression on the engine was perfect. I believe it is becuse with synthetic the engines run cooler, and synthetic still lubricates when it is hot.

If it is a rebuild, I recommend 1500 miles on dino to seat the seals and then switch to synthetic. If the car has about a 100 and is less than 10 years old I have had good luck switching them over. Older than that or with a lot more miles it becomes more likely that they will leak.

Also, if the car has some miles on it say 50k or more, you will want to do one of two things. Either flush the engine with some cleaner, or run syn for 1k change the filter, run syn for another 1k and change the filter. This gets all the junk out of the engine so that it does not cause any problems.

Soaring

All very good points John. But, like I said, if it is only going to be driven a few miles a year, there is no reason to switch to Synthetic. But, if it is going to be a daily driver, then I would also suggest the change and suffer through the few thou miles of leaking. Then, clean up the mess and your engine will enjoy the added lubrication of the synthetic. Regarding "break-in" oil......I don't ever remember seeing a quart of break-in oil. I think it is an old wive's tale that Ford uses break-in oil in their new cars today. Yes, they put in dino and not synthetic. So, my question to you is why use dino from the get-go? To seat the rings? Does synthetic oil not do that? Is there some mysterious reason and qualities about dino oil that has the capabilities to seat rings?

jrrhd73must

Actually, yes dino has properties to seat the rings. It allows a lot more friction, so the friction allows wear and there for seats the rings. The synthetic is to slippery to seat the rings, and new cars will actually use oil if the rings have not been seated properly.

I think all cars can benefit from synthetic. Especially, if it is not driven much. Synthetic oil actually coats the cylinder walls so there is not as much start up wear. Dino oil will drain down, and if the car is not run for a significant amount of time the starts ups will be dry. Also, Amsoil now has oils that provide oxidation protection for engines that sit for periods of time. When I change my mustang oil I am going to use Amsoil Motorcycle 10-40 - since it has been reformulated to battle oxidation.

Soaring

OK, I am not going to go to argue with you, but you sound like an Amsoil salesman. All fluids drain down given enough time, and that would include synthetic oils. Start-up after several months will have a dry second or two until the pump gets the lube to the rings. As far as break-in oil.....who makes that? I have never read an accurate scientific report that states imphatically that dino oil sets the rings any better than synthetic. I have only read reports from auto manufacturers who claim that is the case, and I suspicion that is because filling new cars with synthetic oil is not only more expensive, but that the average buyer would be reticent to paying for oil changes that required synthetic oil.

jrrhd73must

I am not trying to sound like a salesman. I don't push it. To each there own.


This is from the Amsoil website:
Q. I heard that new cars require a break in period with petroleum before you switch them to synthetic. How long should this break in period be?

A. AMSOIL Synthetic Motor Oil can be used during break-in trouble free. In fact, vehicles such as Dodge Viper and Chevrolet Corvette come factory filled with synthetic oil.

Since most new vehicles come filled with petroleum oil, it only makes good sense to change to AMSOIL at the first scheduled oil change interval. New engine components generate high levels of wear metals and can contain contaminants from assembly. By allowing the engine to operate with the petroleum oil until the first oil/filter change interval, the wear metals and contaminants are removed prior to installing AMSOIL.

It goes against everything that I have ever been told.[&:]

Soaring

Me too. I have always been told by word of mouth that dino oil was to be used for the first few thousand miles for a "break-in" period to set the rings. I always questioned that, and have never had faith in the advertising market which purorts that. These engines are not the same as the old engines of yesteryear. Now, with a fresh overhaul on a 289, there may be some metal particles, etc, but how does dino extract those better than synthetic? Therein lies the question. When I bought my new 03 Mach1 , I followed Ford's guidelines to make sure the warranty would be good, so kept the original oil in it for 3K miles, then immediately changed to Amsoil. I guess I didn't hurt the engine, because she is a screaming machine.

jrrhd73must

I think the reason why for dino is it takes longer to break in with synthetic. Ans dino is cheaper to use to break in. With a new harley I recommend changing the oil at 500 miles, then again at 1500 for break in purposes. At 500 miles I have found a lot of metal particles in the oil and I don't want them in the engine for another 1000+ miles. I have never bought a new car so I am not sure what kind of particles are in there.

Soaring

Good sound reasoning, but my Ford manual on my Mach states to not change the initial oil for 5,000 miles. Well, I followed the manual, but then immediately put in Amsoil on the first oil change. She doesn't burn a drop. The break in for a new car is far less time than the old cars. All the parts are calibrated to fit at much closer tolerances than engines like our old Mustangs came with. So, with that, it would be much more crucial to use your method of 500, then 1000 miles to get the metal particles out of let's say a fresh rebuild on a 289.

Brandontyler65

donaldson filters are awesome i got their blackwing air filter and its quality stuff