It all comes down to personal preferrence. I have used Valvoline for 20 years but my 99 Amigo has Wal-Mart's "Super-tech" full synthetic in it as I type. Change the oil on a regular basis with a quality oil and it really shouldn't matter.
Andy

 Hey guys/gals,

 Just a quick question about the best (or better) motor oil to use.  I understand that a lot of it could boil down to whether things like you liking a Ford vs an Isuzu etc.  
 But we got into quite a debate at work over this once I asked the question.

 My wife takes her 2004 Isuzu Ascender to Quality quick lube to get it serviced and the service guy there told her that Penzoil is the best to
 use for her type of vehicle.  Guys at work say that Quaker State would be the best that Penzoil would actually harm the Isuzu's engine and cause
 early wearing and/or breakdown in the engine.  

 She really loves this car and wants to drive it for a long time.... can anyone help out with what would be a best oil to use based on experience.  Thanks
 in advance.

 Mark & Tammy

 --

 "A real friend is one who walks in when the rest of the world walks out."
                                                                                   - Walter Winchell

I can't imagine it would matter...  The other thing to keep in mind is that
the Ascender is really a GM product with a GM engine.  If they don't know
that, then they really shouldn't be telling you what oil to use!

Dad's used Havoline for many years with good success.  That's after
switching from some other brand years ago when that brand had problems with
the oil breaking down.  I've used the same in all of my vehicles except our
02 Trooper (just now over 30k miles) which I recently changed over to Mobil1
synthetic in hopes that it will hold up even better.

Wesley

Hey guys/gals,

Just a quick question about the best (or better) motor oil to use.  I
understand that a lot of it could boil down to whether things like you
liking a Ford vs an Isuzu etc.
But we got into quite a debate at work over this once I asked the question.

My wife takes her 2004 Isuzu Ascender to Quality quick lube to get it
serviced and the service guy there told her that Penzoil is the best to
use for her type of vehicle.  Guys at work say that Quaker State would be
the best that Penzoil would actually harm the Isuzu's engine and cause
early wearing and/or breakdown in the engine.

She really loves this car and wants to drive it for a long time.... can
anyone help out with what would be a best oil to use based on experience.
Thanks
in advance.

Mark & Tammy