Opinions on best engine oil...

[scott123]

Correct statement about same oil different label. I have been in hazmat and liquid transportation for 15 yrs. I have pulled oil from all brands shipping plants to all oil "manufacturers". The only difference is in additives. Detergents and stabilizer.

When an oil company loses a bid for supplying oil the next provider sends in their tankers or rail cars and the plant doesnt even slow down.

Now there IS a difference between reg oil and synthetic. I run full synth in my motors (all 5 vehicles) and trans, rear ends and P/S pumps.

Do a google search on synth and read up. The only hassle is that it costs about 2 1/2 X jiffy lube to do an oil change on your driveway.

[averagef250]

I don't like synthetic myself because it's very harsh to work with. I rebuild a lot of NV4500's in my shop and the synthetic they run on eats the heck out of your skin. Dino oil doesn't bother me a bit. I've torn down 500K mile pickup diesels run on dino with 10K mile change intervals and found no real wear. If dino is sufficient to do that I cannot personally justify spending 2-5 times the amount at every oil change. The funniest croud to me is the older 617 mercedes diesel guys that run mobil1 synthetic, bypass filtration and all kinds of extra protection crap and change thier oil every 2500 miles plus send samples off for testing. I've never seen so much effort put into keeping a crappy 120HP engine alive and running.

My only experience with K&N stuff is on diesels. I've seen several diesels that should have went 400K miles or more have excessive blowby before 150K using K&N filters with regular maintenance.

In the air filter world there are actually real, tangible specifications for filtration media flow and element sizing for particular applications. In pickups and cars you can get away with a very small filter because the engines are usually only running on a very small percentage of thier max rated load and airflow into the engine. In RV's, medium and heavy duty applications where engines run at 100% of rated load for extended periods the airflow through the filter is tremendous compared to light stuff and the filters are sized accordingly. According to filter flow ratings for regular environmental conditions the filter sizes used on pickups is around 1/3 of the actual size it should be to effectively flow and filter the air without significant pressure drop. There isn't much you can do here because there isn't room for a 12" X10" filter element, but I'm not at all sold on K&N's idea that thier media somehow stops more dirt yet flows more.

In addition I think K&N filters encourage poor maintenance since once you shell out the bucks for one youre don't want to replace it and many I see are caked with dirt, making me think guys slap them on and never do any maintenance to them.

A HUGE donaldson 4" outlet 12"X18" filter element runs about $35 and does an excellent job of filtering air. In normal environments with a 250HP engine that filter will last 50K miles. That's pretty safe and cost effective IMHO.

[warponyxlt]

true mr average250 every word

[Fordnatic]

K&N Filters were used for turbine helicopter engines starting in Desert Storm. The turbine blades were getting eroded by the sand kicked up when operating on sand, and the K&N's were the only ones at the time that could keep out the fine sand and still flow the tremendous airflow required. I have run them on everything, even ATV's in the dunes and never had anything get through them, with obvious airflow gains-even having to re-jet at times.

I've recently switched to synthetic oil simply for the easier flow and starting in the sub zero temps which are common up here.