I usually run Rotella 15-40 but the 5-40 full syn. was on sale so I thought Id try it. After 5-700 miles no leaks on my 189K 4.0. I run 500 miles a week so Im hoping to get 6K on the oil changes. At this time I hear no difference in the noises my engine has. Which is a loud lifter that starts about 30-45 second after starting to about 120 degrees on the gauge then it quiets up. I was hoping the syn. oil would help with the lifter rattle. Does not seem to help.Going to a longer oil change duration will save a little money. In the winter the 15-40 is to heavy for Chicago winters. It seems as long as these engines are kept full of clean oil and not overheated they live a long life. Im looking to get 300k out of this before I replace it.

Ron

 

If you wanna do it the 'right' way or atleast what I've been told Is the right way, your supposed to go through several oil changes of increasing levels of syn/conv hybrids before running full syn

 

The 5W40 syn can do 6k OCIs easy. And you're right, this is a much better viscosity for colder weather.

 

I'm sorry, but what you've been told is wrong. There is absolutely no justification for something like this.

 

I haven't found anything to get rid of that either, I have the same thing. Thick oil, thin, MMO, Restore, it still ticks away until it warms up. Just part of it's charm, I guess

 

1. wrong
2. wrong
3. synthetic oils have better dirt dissolving ability, so engine will run with circulating dirt

 

There's a filter for that, lol.

 

i use the rotella (dont remember if 30 or 40) and a k&n filter

 

heres a cool link i found about our oil filters guys check it out you'll be surprised
http://minimopar.knizefamily.net/oilfilters/index.html

 

Absolutely read the above. Then read this: http://www.bobistheoilguy.com/motor-oil-101/

Both conventional and synthetic oils have changed a lot over the years. Most mechanics knowledge is outdated and these days amount to old wives tales and myths. Some of these ideas came out long enough ago that people could remember buying Dexron I made out of whale fat.

 

Run conventional or run synthetic. Do your homework and decide.

There is NOT a wrong choice here folks.....it's personal preference. I run synthetic in my Vette and conventional in all other vehicles.

Both types of oil will provide a long engine life if changed at a reasonable interval.

 

Go to Mobil 1's website they have a ton a videos that answer all of the myths floating around. Yeah, they might be self-serving but I don't think there's argument that full synthetic oil doesn't flow better at very low temps. Check the video where they compare Mobil 1 and a leading synthetic blend oil after keeping both at -40F.

 

The temps don't even have to be that low. If one were to read Motor Oil 101 you'd see there's a difference at normal ambient temperatures as well (75F)

 

Nothing in my post TO THE OP should have given you the impression that I don't know the first thing about motor/gear oil. I've been working on my cars and trucks for 50 years. I don't claim to be an expert but I have learned a few things along the way, so in my opinion the Mobil 1 site is one of many places to go to get some answers regarding the difference between conventional vs. synthetic oil. The video I referred to is obviously an extreme example. You would have realized that had your arrogance not got in the way.

 

Fake oil. Fake butter. Fake politicians. FAKE *****! What's this world coming to?