And fantastic lubricative properties.

On a serious note though, I put in 15W40 this summer and I'm not due for a change til february. I'm in the same climate as the OP, should I change it now, or can I tough it through?

I'm with Brian - use 5w-40 all year, then you never have to think about when the change or leave it.

Plus, if you leave a thicker oil in b/c you just don't want to change it, it might make for some hard starts on those cold Massachusetts mornings...

If it were me I would change it. It will start much easier in weather below freezing.

Another user on here tried to make it through his first winter here in MN with dino oil.
It wouldn't start at 4F. He switched to synthetic the next winter and cold started it near -20F.

Not only does it make a difference in how cold the car will start in, it provides better protection for the engine since it flows better right away when the engine starts turning.

I too run 5w-40 all year. I used to run M1 but they raised the prices and now it is about $7+ difference a gallon around here so last spring I switched to Rotella.

The total cost includes the oil and the filter.

You change the dino oil every 3K.

You change the synthetic oil every 5K or 6K.........depending on the soot loads from your particular engine.

The end result is the same cost.

Ayup!
 

I just opened a national professional account through AutoZone at the school I work at, and was poking around there and look what I found!
http://i153.photobucket.com/albums/s...tella15W40.jpg

http://i153.photobucket.com/albums/s...otella5W40.jpg

Gonna stop in there tomorrow and see about getting some of that 5W40! I was paying $12.99 at Napa (for the 15W40) . . . I plan on running it all year:D

Also found this interesting bit (I like to bottome one!):
http://i153.photobucket.com/albums/s...Thermostat.jpg

What is interesting about that statement is the capability of Rotella synthetic to handle soot loads of up to 9%.

As a comparison, the 617 gets up to about 1% at 5K..........and that's the point where I feel the need to change the oil.

Clearly, I'm way too conservative at 5K and the oil can go longer.

I go 6K on the 603 with similar results (.8% soot).

Actually that is for the dino 15W40, but . . . the synthetic only states "provides a enhanced level of performance" . . . is that compared to their 15W40?

Delvac 1
 

Where do you guys find Delvac 1 and what are you paying?

Rotella = best value
 

I use shell Rotella synthetic 5w40 in my benz all year. Even though its not a "true synthetic" It is the best value for my 300k mile 25 year old daily driver. Its better than regular dino at least. I have thought about using the same oil that I put in my duramax and TDI beetle which is the valvoline 5w40 full synthetic blue extreme. It meets all major diesel engine requirements and is one of the only oils endorsed by cummins, catipillar, volvo, onan, detroit. The bottle says it meets a mercedes spec but i can't remember which one. I dunno what anyones thoughts are on that. It seems to be great oil as at 5000 miles it still comes out pretty clean and I can see no build up or varnishing inside the engine. It also got rid of the valve ticking on my buddies gas chev engine. Only problem is it can be hard to find!

That's not what you want. You want your oil coming out full of ****, cause then you know it's cleaning. The amount of nastiness in the oil should not be dependent on the type/brand of oil. If it comes out clean, then that means it's not cleaning.

How would you know this..........??

Use any API CI or greater rated oil. Depending on how cold it gets where you are you could use 15W or less. http://www.aa1car.com/library/API_ratings.pdf

By clean i do not mean it looks like it did when u poured it out of the bottle. By clean I mean the lubrocity and viscosity has had very little breakdown. There is no sludge or sign of "penzoilitis" as i like to call it:D Yes i am well aware what the oil does to a motor and what it should look like if it is properly cleaning the engine components.

If you are aware of what it should look like...........please tell us all.

Once it goes jet black on a diesel..........you're not going to see much.

Your oil analysis is unlikely to show a reduction in viscosity simply because the oil is carrying varnish or sludge. Additionally, anything of significant size is stopped by the filter.

I have the oil analyzed by a lab every other oil change! costs me $25. sometimes u guys argue just to argue. Any other questions?