I use WalMart supertek in the 5 gallon jugs for like $11, less 10% employee discount (comes out to a little less than $2/qt). Local prices may be different. If you want to argue price to 4 decimal places, don't bother.
Whomever cut open an oil filter and then had the audacity to make a statement on a filters quality is just showing their ignorance on the subject. One guy was complaining about no backflow valve. Not many motors mount the filter in such a way that that is a problem. Some V configs do put a them at weird angles, but nothing that a few rotations of the oil pump won't fill back up. EVERY start is a dry start.
On my 66 M35a2 the cans had no backflow valve and drained back in the crankcase when shut down.. the filters were mounted UPSIDE DOWN and those motors lasted years.
Paper media is a great filter, ever wander what they use in by-pass filters that catch sub 5 micron particles??? hint: PAPER.
As for what viscosity... the motors originally were spec'd with 20 weight oil. Most use 30 and a few 40 if they have noisy internals.
I use 30 in my 270 and 235, and 40 in my 134 because its worn out and needs a rebuild... but still has miles left in it.
Multigrade is fine... 5-20 or 5-30 is probably the best, again, film strength and starting/cold viscosity are the key parameters.
I change oil in my 97 Jeep for $16 (5 qts and a filter). Jeep has 152k on it. Can't find any compelling reason to not do the same for motors that are gonna sit most of the time.
Now for the real can of worms: NEVER ADD ANYTHING TO YOUR OIL.
Last edited by pfarber; 12/22/2013 12:56 AM.
