May have missed it but haven't seen the comment that if you're going to change to from conventional oil to synthetic, you need to do it during the early part of the engine life. Leaks in gaskets and seals have been known to occur when the switch is made in engines in vehicles with a lot of miles on them. Supposedly there are additives that "prepare" engines for the switch but not sure if they work.

I also agree with the comments that a quality filter is as important as the oil, which is why Wix filters have always gone on my engines.

Full synthetic will prevent wear to the bearings over conventional oil

Stick with the motorcraft oil and use a motorcraft or other quality filter. Don’t forget about transmission fluid maintenance.

Dodge 4.7 V8 176000 miles. Valvoline conventional at 5000 mile intervals. With one exception, at 165000, used Valvoline High Milage blend. Burned a quart of oil between changes. Went back to conventional, burns about a pint between changes now.


Ford 3.5 .. 50000 miles. Motorcraft blend, Motorcraft filter. No plans to change.

The base stock and additive package is not the quality of Mobil, Valvoline, and other better quality oil. For the person that trades vehicles at 100,000 miles or less it really does not matter. Disassemble a 150,000 mile engine that has used it exclusively and you will see.

Motorcraft is good oil, it is packaged by Mobil. It is NOT exactly the same as Mobil though.

Went mobile one full synthetic. Will change at 7500 miles.

For the US market all motorcraft oils are produced by ConnocoPhillips using base stocks supplied by S oil in South Korea.
In the past Havoline, Kendall & one other that slips my mind right now have produced motorcraft labeled oils.

In Canada, EU & various other foreign counties motorcraft labeled oils are produced by Mobile using second tier formulations. The same formulas used for other oils they produce for non mobile labeled customers.

All of today's motor oils are vastly superior to what was available as recently as the early 80's.

As long as maintenance schedule is followed or UOA test (used oil analysis) is used to determine service intervals, select the correct API & viscosity/weight & use a decent filter the chances of experienceing an oil caused or related failure is almost nonexistent.

Your sure opened up a can of worms with that one. I've heard multiple recommendations when it comes to transmission fluid. The owners manual for my wife's 2016 Camry states it never needs to be changed for the life of the vehicle. That falls in line with the recommendation I once heard that if you're going to change it, do it regularly. Otherwise, leave it alone. My gut tells me that only applies to cars and never to trucks that pull loads.

The need to flush a transmission seems to be another maintenance item where opinions differ. I've never had one flushed but have always changed the fluid that's in the pan so that much of the existing fluid remains in the transmission. In this way, you might say you're "freshening" the fluid rather than a complete flush. My gut feeling is that flushing a transmission is something that's unnecessary and may actually decrease the life of the transmission, even though the shops sure like to recommend it. IMO, it's much like flushing a brake system, which some of the shops like to push as well. Never done that either and never had a brake issue that was due to old brake fluid.

If I was going to flush a transmission, I would do it the slow way by replacing what's in the pan, drive the vehicle for a week or two (or even more), and then repeat a couple more times until the fluid is mostly new.

Mine is sealed.

Did something change on Pennzoil? My oldest son (bought it when he was 18) put 12 years and over 300,000 miles on a GMC pickup and I put over 600,000 miles on a couple of Chevy pickups and never turned a wrench on the motors. My 2001 went to a neighbors handy man and he has already put another 100,000 on it an it still runs like a top. My 2003 4Runner has a over 150K and still going strong.

Wow you guys could not be more wrong. Do yourself a favor and switch from Mobil to Pennzoil Platinum. 10 years from now and 300,000 miles later you will be thanking me

Bill - if you go to Jiffy Lube and getting full synthetic then it’s PZL Platinum

Mobil and Valvoline got nothing on this.....

https://youtu.be/owqkmJPNKwk

Pennzoil motor oils were mostly made from highly paraffinic crudes. The Shreveport refinery made a a lot of it with Louisiana crudes and I bought the heavy oil byproducts for blending ship fuel. Their motor oil meets all stringent specs.

That said, when I used Castrol in a sports car I had, it never burned a drop. put Exxon in it and I’d have to add oil before the next oil change. Something was different, but I don’t know what.

Used castrol in my bike. Good stuff.

What is synthetic made from?

Depends on the type of synthetic. Some, polyalphaolefins, are primarily made from natural gas. Others, severly treated hydrocarbons, are made from crude.