too late for synthetic motor oil?

[Snoop1965]

95 F150 4wd/4.9L 6/118K miles

i've heard that if you start using synthetic engine lube on a higher mileage motor you might run into problems.

i plan on keeping this truck as my daily driver for at least 5 years...burns 1 qt every 3 thousand at the most (burns very little on short trips- extended highway usage is when it's the worst)...has a light tick at idle after being driven awhile but other than that (and a drivetrain problem i'm trying to figure out) it's a pretty clean rig.

thoughts on switching to syntetic to extend engine life?

[johnboy427]

Try posting this on the Oil and Lubrication forum, but I don't think synthetic oil will do any good for you I have actually heard it is bad for motors with flat tappet cams because it doesn't have any zinc in it I think. I run Shell Rotella 15w-40 in mine and its still running strong at 275,000 miles. Be sure to use an oil filter that has doesn't let the oil drain out while it is not running because the filter sit horizontally and all the oil will drain out when you shut it down causing dry starts, mine makes all sorts of racket for 5-10sec if i buy cheap filters the Motorcraft FL-1A is the best in my experince.
-Johnboy

[srercrcr]

Word is you might develop some leaks switching over. Some say go the semi-syn first and observe. Personally I don't see the need...these are loose-tolerance engines, designed around regular oil. I'm at 175,000 on my 83 all using 10w30 or 10w40 regular. Has never dripped or burned a drop in 25 years.

[Silver Streak]

I doubt there is any benefit in running synthetic and there certainly isn't enough to justify the added expense. Any problems synthetic causes were there anyway, they just weren't apparent with dino-juice. Sythetic is good stuff and I will use it in my new engine if I ever get it done. Good old fashioned 10W40 has served me well for over 335k miles, so why change?

[Milwaukee1979F150]

Don't use those or it will blow tons of blue smoke all time.

It improve oil pressure when it new but maybe 500 miles later it start low more fast than normal oil then sudden it less pressure then not good lucubration those old engine it just moving fast no time lucubration it.

[srercrcr]

What............?

[Milwaukee1979F150]

Sorry for my bad English.

My Friend who thought it good because he heard it would save 1 to 2 mpg so he try synthesis oil in 4.9L that have 170,000 miles it worst. Run awful why blue smoke all time out muffler.

foul spark plug because oil so thin it enter in cylinders.

Lucky he switch to normal oil like dino 10W30 now it ok but synthesis oil is for newer engine.

[Silver Streak]

There's something else wrong with that truck. If synthetic oil caused that it was because it was the wrong synthetic oil.

[4x4 Bart]

Synthetics have changed drastically in the last few years. Most folks are under the misconception that synthetic means man-made. This is not necessarily so. In the late 90's Mobil sued in federal court to prevent another company from calling their oil "synthetic" when it was really just a high grade stock ( class IV). The court ruled against Mobil and stated that the term "synthetic" was just a trade term and had no exact specifications. So now as consumers we don't really know what is in a bottle of oil.
Don't get me wrong. Most of the oils that say synthetic are far superior to the cheap stuff, they are just not all that exotic. You get what you pay for. If you pay $6.00 a quart and up you may have a better chance of getting the real thing but who knows. Try and find out exactly whats in a quart, it's impossible. You just have to trust a brand.
I don't think you will have any problems changing to synthetic and if you are lax about changing your oil when you should, you will gain some benefit by this high grade oil.
Just my two cents.......Bart

[srercrcr]

I'm sorry but this is jibberish. Synthetic oil is refined from chemicals (which are derived from oil). There are standards. Synthetics don't create sludge, they withstand high temperatures, they are cleansers of the engines. They are far superior, but at a cost. I use them for my newer cars which are built to closer tolerances that my 300, which I still use hydrocarbon oil.

[Snoop1965]

if these "synthetics" last beyond 3000 miles what about the filter?

[srercrcr]

3000?? All oil last longer than 3000. I believe the mfgrs recommend 7500. Fine, settle for 5,000...keep the math sumple. If you're changing that precious oil at 3000 thats wasteful. Forget drilling in ANWAR, here's our problem!!
My late model Explorer: I used my local repair shop's recommendation for synthetics....change filter at 5000 and top off the oil. Replace all the oil and filter at 10,000. I use Walymarts Supertech Synthetic....something like $9 for 5 qts...a deal. How's it working for me? After 130,000 miles since I got it new....no burning of oil whatsoever, no drips, starts and runs today the same as Day 1. Case closed.

[Silver Streak]

Originally Posted by srercrcr

3000?? All oil last longer than 3000. I believe the mfgrs recommend 7500. Fine, settle for 5,000...keep the math sumple. If you're changing that precious oil at 3000 thats wasteful.

BS. You should see my oil after 3000 miles. I'll be damned if I leave it in there any longer. Even if I did, the truck starts spitting it out at about 3000 so it would get changed pretty quick after that just by attrition. On new cars you can go longer. On old cars that isn't a luxury.

[srercrcr]

So how come I see my syn oil getting dark by 3000 miles, yet don't change it until 10,000 miles and everything is like new at 130,000 miles, huh? The color says it's working as it should but it doesn't need changing. Heck, why not change it every 1,000 miles? Reduce Mideast oil dependency....change oil at 5,000 miles! Do it out of patriotism!

[Diesel Man 03]

Don't be fighting boys, I think the local repair places are the ones that brain wash people into changing oil that often.I myself don't change until at least 5000 miles.