[johnmyster]

I've never been convinced that synthetics are any better. Castrol GTX is my fave. Pensoil, Valvoline, or whatever is on sale.

On a given oil change, half of my driving will be long (400 mile) highway trips. The other half will be 2-3 mile trips to the store. I don't commute by car. Thus, I'm changing my oil more often to get the "short trip residue" out of my crankcase. The promise of long life oil wouldn't be a good idea for me.

I will, however, spend money on a better filter. Years ago, FRAM won acclaims for their filtration. However, I think their quality has gone down. The nicer FRAMs, Toyota, Mobil, Bosch , and Motorcraft (Ford) filters get my approval along with some others. I always open the box, and look for a "reverse flow seal" that is made of softer (red) rubber and a non-stamped top plate. The stamped plates always have buggers on the back of the holes that keep them from sealing well. I consider these backflow preventers to be critical in getting oil to your lifters and valvetrain quickly during startup. They help to prevent "drainback" when the engine is shut down. I like the grippy on the frams, but will only use their silver filter. Since I have a GM, that usually leaves me using Bosch, Silver Fram, or Mobil. Always liked the Motorcraft when I was a ford guy...

If you open the boxes in the store, you'll quickly see that it looks like only one or two companies out there make filters...

80/90 wt is my fave for differentials, though it smells like dinosaur poop. A lighter oil seems to be better for manual trannies - easier on the synchros. GM reccomends their own blend, and pensoil is the only company that makes it - at $6.50 a quart it may as well be synthetic. I'd rather change ATF more often than run synthetic and pretend it lasts any longer.