William Berry

Agree first time ford owner at 60 got caught at a weak moment PERHAPS .... jumped on a super clean 07 fx4 5.4 with 125000 miles for under 5 k USD while wife was out of country took her for 5-30 penzoil platinum synthetic the other day after researching

ShirBlackspots

Its better to use 5W30 in the 5.4L, synthetic and thicker oil is better for the engine.

LariatDude

Problem with synthetic on these high mileage engines is that the fully synthetic oil may seep past the oil pan gasket due to its nature. Whereas Motorcraft 5w-30 blend works great (on mine at least). Motorcraft actually has some of the best oil and is perfect and low costing vs the more expensive synthetic oil

dukedkt442

5 quarts of full synthetic at Walmart is around $22. Motorcraft is around the same price. I picked up 3 5 qt jugs of Pennzoil Platinum at Autozone back in March for $17/jug at Autozone. Benefits of full syn far outweigh the negatives, never had an engine start leaking after switching and I've switched several vehicles well over 120k, including my 35 year old truck. Due to timing jobs, few of us are stilling running original pan gaskets anyway.

hahanson

That's total BS. Please provide some facts to back up those statements.

LariatDude

What’s BS? I said it MAY leak. Full synthetic has special properties to it and because of those the oil may seep past an original gasket if it’s worn. So I was told on this forum at least by someone high up. And it’s been proven with oil analysis that Motorcraft has great protection and additives for cleaning. Not saying anything else is subpar. Js nothing wrong with Motorcraft. And location depends on pricing my friend, over here I’d pay double the cost for full synthetic vs the blend with Motorcraft

hahanson

Oh I have no issue with your liking Motorcraft blended. My issue is your statement it's less prone to oil leaks than full synthetic. That's a common myth, and you should know better than that. If a gasket is worn Motorcraft will leak just as much as say, Mobil one or Pennzoil.

But if you reference some study that shows blended leaks less than synthetic, please share and I'll happily change my tune.

SCORGE

I did a brief stint on 5w-30(about 10,000 miles). Went back to 10w-30.

LariatDude

The logic behind synthetic oil is that it has better cleaners in it right? So I guess to reword my poorly stated post, if you switch to synthetic it may reveal leak problems already existing. Leaks that were plugged or sealed by the deposits from the synthetic blend oil, thus no evidence of it

hahanson

Well, not really. I mean if you look back at some of previous posts in this thread, it's quite a bit more complicated than that. Also, it's not like Motorcraft blended has LESS cleaning agents than the typical full synthetic (or even conventional for that matter, at least with the more reputable brands). The short answer is synthetic oil does not break down as quickly and holds it's viscosity more consistently over greater temperature ranges (flows better during startup and when engine is cold, isn't as thin when engine is hot), among other things.

Today's conventional oil probably matches or comes close to many of the advantages of synthetic over the short term given the detergent additives they use, viscosity and friction modifiers, etc.

The differences have more to do with the petroleum base, not the additives.