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In a hurry with COLD ENGINE. State Patrol recommends Mobil 1 full synthetic oil

Ford specifies their 5W-20 Motorcraft synthetic blend motor oil in thExpedition.
With a cold engine and I must hurry, would the full synthetic oil be.tter?
Would Wal-Mart’s full synthetic oil be as good as expensive Mobil 1?

Thank you.

Mobile 1?
Is that brand of motor oil sold only in Alabama?

;–))

(Note: The brand is MOBIL 1)

Anyway, if I was in the position of having to drive at high speed right after a cold start, I would definitely be using a full synthetic motor oil. Whether Wal-Mart’s full synthetic is as good as MOBIL 1, I can’t say, however.

But, of course, that leaves the issue of what you are doing to your transmission and your differential with high-speed driving right after a cold start in sub-freezing weather. You might want to think about using synthetic lubricants for everything, not just for the engine.

Thanks, VD. (I thought Mobil looked strange and changed it. I’ll change it back.)

Yes, I considered changing everything, but for now full synthetic oil can easily be used next oil change.
Hate thathere is no transmission dispstick on this 2008 Expedition.

A Full Synthetic, Such As Mobil-1, Is Specified By GM For My Car At Extreme Cold Temperatures (Below -20*F), Unless One Wants To Switch To Thin Conventional Oil. I Use Mobil-1 EP All Year.

Since full-syns flow better at cold temperatures and work better in high temperatures, it just makes sense.

How much will you save buying Wal-Mart oil ? I Buy the more expensive Mobil-1, Mobil-1 Extended Performance at Wal-Mart and it’s only something like $27 / 5 quarts. The regular Mobil-1 is even cheaper.

VDC’s idea of running full-syn lubricants in everything sounds like a good idea. I believe many of the fluids, like trans fluid, in many newer cars, is already full-syn filled at the factory. I think GM’s Dexron Vl is an example of that. I don’t know about Ford. Check out their fluid.

CSA

I also agree with using synthetic fluids in everything, but would especially recommend doing so in the differential. The transmission heats up fairly quick due to its “cooler” being in the radiator in most cars, but the differential oil can be like jelly at subzero temps and you can expect accelerated wear if you immediately subject it to high torque.

I think using a synthetic is overkill for cold starts. I lived for years in Northern Maine (minus 70 degrees) and Alaska (minus 40 degrees). No problems at all with conventional oil. If you need the sense of security with synthetic oil then by all means use it.

"If you need the sense of security with synthetic oil then by all means use it."
Engine starts immediately. My sense of security is unimportant. I just want to minimizengine damage if possible.

Funny, when a hospital calls at 3 a.m., I have gone to the vehicle in my sweat suit (what I sleep in), started the vehicle and moved it to the end of the driveway. Then scampered back into the house to get dressed.
Then drive gently through the neigborhood and mostly down grade to the arterial.
With such low load, the engine is still cold.

It’s not going to hurt anything.

Robert…I think you misunderstood my meaning of security. Your sense of security about your vehicle is very important or you would not be worried about engine damage. State Patrolmen are policemen so why should they know more about engine oil than the designers of your vehicle engine? I have over 40 years experience as an automotive mechanic and a diesel mechanic so I know a thing or two about engine oil. 5W oils were not designed to extend the life of your engine. It was just a means to increase fuel economy. Synthetic oil will not harm your engine and it’s won’t extend the life of it either.

Exxon manufactures more than just one blend of Mobil1. There is a regular blend that does not have the extra additives that Extended Performance does. It should be less expensive, too. BTW, Shell manufactures Walmart SuperTech motor oil.

I respectfully disagree with missleman. I believe synthetic WILL increase the longevity of your engine. But for most people it may be overkill, as the body and other components will typically wear out before even a worn engine quits.

If synthetic wasn’t superior to dino oil, it wouldn’t be factory fill in high performance cars, used exclusively in F1 racing, and required in Volkswagen and other vehicles with turbos if you don’t want to void the warranty.

Take a quart of Mobil-1 and the same weight of dino oil and leave them outside overnight when it’s below freezing. Now uncap them and pour. It will be pretty obvious which oil flows better and starts circulating quicker in your engine.

How about just put a sample of each oil in the freezer, which is ~0F.
Just don’t let the wife know what you’re up to. ;o)

Without putting words in @missileman. 's mouth, I would say that under normal conditions, non turbo, regular change intervals, proper warm up, moderate temps etc. that Mobil 1 IS overkill. But, like the state police do in our state, where 10 k oil change intervals are the norm with no warm up before hard use in cold weather, synthetics definitly have the advantage. Even if the the wear factor were taken out of the equation, having a vehicle that runs smoothly from the get go in sub zero temps, is a definite safety advantage.

Robert Gift:
If you switch to Mobil 1, do you think you’ll own the vehicle long enough to see any difference in engine life?

ThExpedition starts instantly and runs smoothly.
But now I regret not having used Mobil 1 at the last oil change for when the Expedition is pushed too early in frigid conditions.
Then go back to Motorcraft 5W-20 synthetic blend in Spring.
For now, I’ll continue starting the vehicle in my underwear and moving it out of the garage, then put on my medical uniform inside the vehicle while it is moving up the street in idle.
Such cold seats thoroughly awakens one.

"If you switch to Mobil 1, do you think you'll own the vehicle long enough to see any difference in engine life?"
That is my other consideration. Would there be any noticeable affect which matters? Or just theoretical increased detriment? A 60° drop in temperature feels like a lot to me, but does such mean anything at all to metal or an engine? Th.is why I have not botthered with a block heater or my outdoor floodlight bulbs shining up against the differential, transmission and oil pan.

Robert:
Opinions will likely vary on the answer to this - since it is a subjective question.

My view is that if you use Mobil 1 over the recommended 5W-20 synthetic blend to decrease wear with your cold starts, your engine may exhibit slightly less oil consumption as it approaches the 300k mile range.

Aside from the oil flow problem in cold temps, oil does not lubricate nearly as well until it gets closer to operating temperature. Plus on a very cold engine (and transmission, etc.) different metals have different coefficients of expansion and contraction, and the engine parts are not in the normal “shapes” they are in when the engine is warmed up. So your engine’s tolerances are different and parts that normally fit like a glove may have increased friction due to tightness or extra play such that they bang together. Combine that with worse oil flow and oil that hasn’t warmed up and you get excessive wear.

Will you see a difference? Maybe, maybe not–it depends on how often you stress your engine like this, how good your oil is, how good of an engine design, and of course on whether you get rid of the vehicle before the engine gets noticeably ‘tired’.

For this application I would use a 0W30 full synthetic and use a block heater, if practical, to keep the engine block warm. With that much invested in a vehicle a little extra cost will ensure the engine and valve gear have a long life.

Here we go again.