Man I think I'm going to try Mobil 1 10-40 RP is to pricey but do you guys us any additive like Lucas? Also I never had a vehicle with over a 120,000 miles on it should I stick with 10-(40)
40 is thicker right.

 

If you need a oil additive then you need a new oil.
Just use a good name brand full synthetic, change it every 5,000 miles and dont worry about it.
Stick with the 10w-40, that is the best weight for most people.

 

Basic oil explanation. The first number is the weight when the oil is cold, like after sitting overnight. The second number is the warm weight of the oil. The lower the number the thinner the oil. Your owner's manual has a chart listing what weight oil for the ambient temperatures. You'll notice that the warmer ambient temperatures recommend a thicker oil such as 10-40 while colder temperatures call for thinner oil like 5-30.

When using synthetics it is not as critical to change your oil weight based on ambient temperatures. Synthetics are not effected as much by ambient temperatures as conventional. With synthetics, most places in the country, you can get away with running the same weight oil all year round. Only if you expect to encounter extreme heat or cold should you need to change oil weight.

I used RP 15w40 in my diesel all year round in Alaska and Arizona. Neither place did I experience any trouble with the oil.

The thicker your oil the quieter your engine will likely run. The thicker oil will take up the gap in lifters and push rods.

 

Great all around to the point explanation AK.
Just to add if you have increased oil consumption (more than 1 qt per 1,000 miles) then switch to the next higher grade of oil.
For example, if you are using 5w-40 and you need to add 1 or more quarts every 1,000 miles or less then switch to 10w-40.

 

Time is not the factor, contamination is. RP is the same as the mobile1 and any quality synthetic. Castrol syntec is conventional that is refined in a way that it qualifies to be a synthetic, but will not hold up under an oxidation test.

Contamination is the only problem. You do not have to change oil based on time, only mileage, or time used. Most people do not have idle time as a factor. Only truck drivers, which is where your thinking is coming from. I ran a Western Star 1 million miles without a change. 2 ceramic bypass filters, with extended filter changes, but only add oil. The pan was never drained. It was of course, monitored by regular analysis. Quality synthetics do not break down like conventional oil, but they do get dirty just the same.

 

I guess I didnt convey my point very well, repeated short trips will contaminate any motor oil faster than driving down the highway.
He stated that he drives frequent short trips and this will contaminate the oil quickly.

I drive the expressway and have lots of idle time, so that is why I use the oil that I do.

 

I was on Mobil 1 website and I was looking for Extended life and all I found was Extended performance and I didn't find it in 10-40 but I found this....
Available as:
Mobil 1 Extended Performance 5W-20
Mobil 1 Extended Performance 5W-30
Mobil 1 Extended Performance 10W-30
Mobil 1 Extended Performance 15W-50
I didn't see extended life 10-40 where do you guys get your oil?

 

Sorry, I mis spoke before, I use Mobil 1 5w-30 SUV in the winter and Mobil 1 Extended Performance 15w-50 in the summer.
I buy my oil at Wal-Mart as they have the best prices on it.

When the Pep Boys in my area went out of business I bought 3 cases of the 15-50 for 60% off.

 

FYI The Extended performance 15-50 will be discontinued this year 09! better go stock up!
I would have to read it again but I think they said it will me called Mobil 1 15-50.
Hmm I want to start using 10-40 for winter any experience with Mobil 1 clean high mileage oil anyone??

Outstanding protection for engines with more than 75,000 miles.

Proven protection of critical engine parts from lubricant-related failure for 5,000 miles or six months, whichever comes first.

Includes seal conditioner to help prevent leaks in high mileage engines.

Does not require a special oil filter.

Designed to exceed the latest engine warranty requirements.

Mobil Clean High Mileage motor oil provides the same boosted cleaning performance as Mobil Clean 5000 to help control the formation of sludge and harmful deposits, and to keep engines cleaner longer.

It is not necessary to use a special oil filter or to flush the engine prior to changing to Mobil Clean High Mileage.

 

That Mobil Clean is NOT a full synthetic motor oil.
Full synthetics have more detergents to clean your engine than a conventional oil does.
That Mobil Clean is a conventional oil with added cleaners.