changing from normal oil to synthetic?

[FX1]

this was my uncles car prior to me and by looking at oil change records i think he always used reg oil. i think ive seen a discussion on how its harmfull to go to reg oil if synthetic was used but what about the other way around? My car now has 84*** miles on it now. i would ask him myself but i need a ouija board.

[FordNut]

Switching to synthetic may cause leaks around gaskets and seals. Then again, maybe not. Some cars leak after the switch but others don't.

[a_d_a_m]

I switched on my Magnum and haven't noticed any problems.

[Mr. Man]

Use the proper viscosity and you shouldn't have any issues. I think the MM uses 5w-20 or 30, it's labeled on the oil filler cap.

[rayjay]

If your uncle was using MotorCraft 5-w20 semisynthetic that came in these engines, then you would have no problem switching over to full synthetic.

I am sure our resident oil expert will be in here shortly with the correct answer.

[Ralph Sr.]

dont the marauders come with factory stock ford synthetic ,type oil ? after 2,000 miles changed to mobil one 5w-30w. no problems with either one !.. i think better with synthetic oils- more expense , but better protection and longer on miles, before oil changes..

[RF Overlord]

FX1, the myths that you can't (or shouldn't) go from dino to synthetic, or that you can't switch back once you do, are just that: myths.

The only possible negative to switching from dino to synthetic is that if the motor has a LOT of miles (84k is not a lot) or has been abused or neglected, then you may have some sludging and/or seal-hardening and the synthetic may find some small leaks while it cleans out the sludge and reconditions the seals. These leaks usually abate after a short time. If your motor has been well cared-for, you will have no worries. Use whatever oil makes you feel warm and fuzzy.

Ralph Sr., the factory fill was (is still) the same Motorcraft 5W-20 you can buy at Wally World or any auto parts store. It's a synthetic blend made by ConocoPhillips.

[FordNut]

My built motor leaks with synthetic but not with petroleum. NOT A MYTH...

[FX1]

Thanks alot everyone. Im going off looking at old receipts. He would spend anywhere between 20-30 bucks everytime so i assume it was just reg oil.The car was maintained very well so im thinking about going with synthetic next time.If i aquire any leaks ill let you know FORDNUT..JUst So you cant tell me"I TOLD YOU SO"

[FordNut]

Try the factory specified synthetic blend...

[RR|Suki]

My built motor leaks with synthetic but not with petroleum. NOT A MYTH...

So does mine, I call it the cost of doing business and run Amsoil 5-30, might go to 10w-30. I doubt the stock main seal etc. would have the same problem though :confused:

[fastblackmerc]

With a stock motor switching between synthetic & dino won't be a problem. As stated, it's a myth.

[ctrlraven]

The only issue is switching back and forth a lot between regular dino and synthetic. If you change it to synthetic stay using it from there on.

[RF Overlord]

I'll say this again: if the motor is in sound mechanical condition there is NO PROBLEM switching between dino and synthetic at your convenience. Your motor does NOT know the difference.

The ONLY issue is when the motor has been abused or neglected and has sludge build-up and/or hardened seals.