high mileage vs synthetic oil

[Gussie2000]

Not sure what the PO used, but I use Quaker State 4x4 Torque synthetic. It is a bit cheaper than the Castrol synthetic, but I use it in both my toys. Another good question, how about oil filters, I personally use the FRAM tough filter, but I am gonna guess that they are all about the same.
Speaking of maintenance, I replaced my fuel filter today, I swear it runs better and better throttle response. I am pretty sure it was the original filter at 117K miles.
My fuel pressure regulator will be here tuesday. Cleaned the TPS, which wasn't really all that dirty. New dielectric grease in most of the connections under the hood.
All in all, as far as oil, I think that as long as you do it regularly and use the appropriate weight for your weather, they probably all work out the same. (I am still gonna run synthetic)

That oil seems to be good quality though,i consider this # 1 on my list if mobil 1 ever ran out of stock.

[BigSwede]

80K isn't high mileage, at least not in my book. I use Mobil One in my Trooper, 128K miles, doesn't burn any oil so no reason to change.

[twistedsymphony]

if you have a formula that works, then there is no reason to change.

you might see some detrimental effects switching from regular oil to synthetic on higher mileage vehicles because sludge builds up around the gaskets and in crevices with regular oil and synthetic will clear that out, and while that might sound like a good thing, consider that the build up also keeps those areas from seeping oil...

I've had more than one car that started burning and leaking oil after switching to synthetic.

some older sensors have problems with synthetic oil as well and the synthetics can gum them up... I have a friend who is a Subaru Technician, apparently the owners manuals stated to NOT used ANY synthetics in their motors, and there are only certain tested brands that they'll let you use without voiding your warranty.

synthetics are nice sometimes but it's not a clear cut better oil than the regular stuff.

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as for filters, they're much more important than the oil you use... every mechanic and oil filter comparison I've seen has revealed 2 things

1. there are really only 4-5 filter manufacturers and most companies buy one of those and re brand it, (though there are sometimes subtle differences)
2. 90% of the filters out there are COMPLETE GARBAGE

kind of old but here is some good info on picking the right oil filter:
http://www.knizefamily.net/minimopar...ers/index.html

I use either K&N, Mobile 1 or Purolator in my cars, depending on which one I can get cheaper (they all have the same manufacturer). though the best filter you can get is made by "WIX" who make filters for most OEMs as well as the generic NAPA band.

FRAM is down right horrible, you'd be better off stuffing cheesecloth in a can.