TV Question?-Synthetic Motor Oil

[ForestCreature]

Tracy
 You would be better off switching to 5w30, full synthetic, according to my "certified mechanic" son. 5/20 is fine if the outdoor temps are going to stay above 10 below zero, but if it were his car he'd switch to 5/30.... to quote him "5w30 is like running water thru the engine"
 
 We run 10w30 in the van, Mobil1. Be sure to get a quality filter as well.

[springer02]

We've used ful syntehtic in our three Jeeps for years and it must be doing something right as my '99 has 102,000 miles, our '94 Wrangler has something like 85,000 and the '03 has around 30,000 miles.  One thing we've noticed, though, is that the oil pressure gauge reads higher when using synthetic oil.  We talked to a Jeep engineer at Camp Jeep and he said that was a-ok.

DH does our oil changes in good weather and we go to a "Jiffy" place in bad weather.  The oil and filter costs something like $30 when "we" do it ourselves.  I say "we" because my job is to take the used oil to the dump for recycling!

Tena

[tlhdoc]

Tracy
 You would be better off switching to 5w30, full synthetic, according to my "certified mechanic" son. 5/20 is fine if the outdoor temps are going to stay above 10 below zero, but if it were his car he'd switch to 5/30.... to quote him "5w30 is like running water thru the engine"
 
 We run 10w30 in the van, Mobil1. Be sure to get a quality filter as well.

If I had any engine problems and I wasn't using the 5W20 I am sure Ford would tell me it was my fault for using the wrong oil.  I will not take a chance on damaging the engine.  Ford has changed the recomendation for a lot of their vehicles from 5W30 to 5W20 oil.  

[wynot]

Tracy,

Actually, Ford went to 5W20 for CAFE reasons, not for anything else.  (So says the material I have read about it.)  Apparently, if a manufacturer uses a specific oil to meet CAFE, they MUST recommend it as the oil to be used in the manual.  There should be no problems using a 5W30 synthetic in its place.  If you have more than warranty mileage on that Explorer, I would be looking at alternatives to 5W20, but that's my thought.
 
As general comments, from my decades (literally) of watching the various oil recommendations change and following this stuff with interest-
 
1. Synthetics are not miracle products, but they do bend the rules somewhat.  Because they are engineered products, they flow better in severe cold, and hold viscosity better in extreme heat.
 
2. Synthetics do not resist contamination any better than a mineral oil, but they tend to have better detergent and additive packages.  So, if for instance, you run a cold engine short distances, you still will have fuel dilution of the oil, regardless of the type used.
 
3. Synthetic oil does get dirty.
 
4. Synthetic oil may give a miniscle amount of better fuel economy.  But your savings at the pump will not pay for the oil.
 
5. Synthetic oil may provide some safety margin on badly maintained and serviced engines.
 
To sum up -
 
I sincerely doubt that if you maintained your engine religiously with either mineral or synthetic oil, that you would see a difference in the life of the engine.  I've had cars run hundreds of thousands of miles with no problems on 10W40 mineral oil.  I've also had an engine fail with full synthetic in the crankcase, which wasn't the oil's fault, but Ford's.
 
Synthetic oil is better than conventional oil in all areas but cost.  It flows faster at startup, doesn't cook at high temperatures, doesn't boil off - leaving you with 20W30 oil instead of the 5W30 you put in.  However, it has two nasty habits instead for older engines.  Since it remains 'thinnner', it tends to leak more in engines that already are tired or leaky.  And because of its detergent being more aggressive, it will tend to remove deposits that may have kept an engine from leaking or using oil.
 
I don't believe in Amsoil's claims of mileage (12,000 or one year) change intervals without using oil analysis.  I believe there are people who can run an oil that long because of the type of driving they do, but not as a standard rule of thumb.
 
So, what do we do?
 
*I run Mobil 1 synthetic 5W30 in the Tahoe.  Change when the oil change light comes on, whether it is at 3,700 miles or 8,000.
*I run 2 qts Mobil 1 15W50 and 5 qts of Quaker State HDX 15W40 in the Mercedes diesel.  Change at 5,000 miles (has a 7,500 mile recommendation)
*I run Quaker State 10W40 in the Audi.  May change to full Mobil 1 here.  It only has 78,000 miles on it.  Change at 5,000 miles (7500 mile recommendation)  Based on some 'info' my trusted mechanic told me, I may be better off going to synthetic on this car.  The Audi has a tendency to suddenly increase its oil consumption and drink a quart of oil somewhere after 3,000 miles.  Mechanic told me that that is a sign that the oil molecules have sheared (lost their ability to become 30 or 40 grade oil when hot) and is running as a 10W oil.

[tlhdoc]

Kershner I only have 2700 miles on the Explorer.  DH is changing my oil as I type this.  For this oil change I am using the Motorcraft 5W20 that I had left over from the other Explorer.  I will start using Mobil 1 5W20 for the rest of the cars life.  DH is insisting on it. :eyecrazy:

[PopupSgt]

Tracy,
I must have missed something, did you get a new explorer?  I knew at the rally your current explorer had around 50k miles on it.