Hey all. Ran my first batch of Shell Rotella 5W40 Synthetic. 15,500 KLMs or about 10,000 miles. Baldwin oil and air filters. No filter change in between.

Only plan on doing this again for the colder winter months.

For those interested....

Aluminum 9
Chromium 2
Copper 8
Iron 11
Lead 3
Tin 0
Silicon 19
Potassium 21
Water 0.1
Oxidation 3.6
Viscosity @ 100 13.7
Glycol None Detected
Fuel <2.0
TBN 9.7
Nitration <2.0
Soot 0.6


Was concerned about running double on milage for this. But it seems like it turned out well. Numbers show reasonbly well.
Ran double the milage because the cost of synthetic was double the price. Noticed that once the truck has warmed up (in the winter) it showed less oil pressure. Now that I have Rotella 15W40 mineral oil back in, the pressure is fairly higher. I equate this to that synthetic has better characteristics to flow.... Pressure is created by "resistance to flow"

Just curious, how long does it take you to roll the milage? I run the Shell Rotella 5W40 Synthetic during the winter as well but don't rack up a ton of miles and at 7K miles mine was pretty dirty visually. I since have gone to changing every 5K.

Oil was changed last November....till mid April. Shoulda put more milage on than I did. Normally gets done every three months, give or take a few weeks.

I use the same and change every 6k......takes me about 2 months....... fuel and tranny filters every other change.

i do the same thing every winter i run 5W40 shell synthic for 10,000 miles i change it in november along with a fuel filter and dont do a thing until late march or early april i tow a 3 place snowmobile trailer loaded about 5000lbs for 6500 or 7000 miles of the 10,000 and then change back to 15W40 for the summer always shell rotella i have had oil test on it twice just to check for fuel in oil because this injector crap everything is a ok p.s the oil pressure will be a little lower with5W40

silicone seems high....double digits....

For the most part I drive about 10 miles per day (5 miles each way) to and from work. Should I change my oil every 3 months, 3K miles, or when the "GM system" says it needs to be changed?

Depends on your level of paranoia. Five miles is hardly enough time for the oil to get to proper operating temperature even if the water temperature is up to 'normal'. Water condensation would be a worry in those driving conditions. Do you take it out on weekends for an extended drive so any water is boiled off?

Eric; I put a new Baldwin air filter in, three weeks before the oil change. I suspect that is the cause for.......

Thanx for the input.