Well, thisthread lost its chance to be the first "oil thread" on the internet that did not devolve into a turd hurling contest. FWIW (nothing): I use Amsoil in everything from the lawnmower to the BMW (Newbie ducking for cover before someone mentions that it isn't onGM's 4718M list)

 

Amsoil in my gassers and rotella synthetic in my diesel.

 

I use 15-40 diesel oil for the cummins,..in the chevy I use what ever the dealer puts in.

 

Have any of yall used Castrol Sentec full synthetic oil! Been using it for a good while now on all my vehicles including my 2003 yamaha 1300 bike and no probs. My nextdoor mechanic uses the same as me but who are we to tell! All I can tell you is I like the way the oil looks when it comes out during an oil change (colorwise) and I like what the label says on the oil container. Good luck! Steve Meyer in Louisville Ky.

 

Yes, I haveused Castrol Syntec in my tractor and diesel utv for a good many years. Never a problem.
Use Mobile 1 in Vette and standard Castrol in Silverado.

 

Here in Alaska just north of Anchorage I use Mobil 1 10-30 in the summer, 5-30 in the winter in my 2002 Silverado 3500 with the 8.1, Since I am a heavy equipment mechanic I have complete faith in Baldwin oil filters as they are made for extreme conditions plus they filter out better than the others and you are not just paying for a name or a gimmick. I was told they filter down to 3 micron where the others are only 5 at best. During the warm season I go up to 2000 miles on my engine which is about 90,000 miles right now and in the cold winter months I change every 1500 miles but thats because it gets near -50 up here then and the motor does not really get hot long enough to cook out any condensation so thats why, being a mechanic all my life I know cold weather is the hardest on any engine.

 

Honeslty in my opinion, as long as you service your truck on time every time, i don't think it really matters what oil you guys use. Have you ever blamed a blown upengine on the oil you were using? Can you honestly tell a noticable difference on power or temp when you switch to those very expensive synthetics?

 

of course they can. they are all so skilled mechanics and so in tuned to their vehicles.

i feel like i am in flippin kindergarden...

 

I most definately know what will happen to two diferent bottles of oil left outside in MINUS 40 degree temps, both are 10-30, one synthetic the other any name brand dino oil. A Pure straight synthetic will still pour out of the bottle, it will be thicker but it will still flow enough to pump through main journals. Dino type oil has to be cut out. We use pure synthetic in Alaska in most cases where we do not either heat the oil or leave the engine running all the time. I use a Delo straight 40 weight in the fleet of concrete mixer trucks but during the winter we plug the trucks in and it also heats the oil.

Also synthetic by its base acts as a solvent and cleans the engine, I basically am sold on Mobile 1 because its cheaper than the others and is always available at Walmart. In some technical references some claim it isn't PURE synthetic but it tested out Alaskan tough for me.