Having some Issues During a Long Trip
 

During my 380 mile trip from potsdam ny to boston, the dash threw the "Oil Low" warning, so I pulled over on the mass pike to one of the service plazas (20 or so miles after the warning popped up). They had NO synthetic oil whatsoever so I put 10W30 Penzoil (about one quart) in. I was wondering if its alright to mix the oil like this, and also if I should now have it changed to fully synthetic Mobil 1?

Also the range estimator has been ridiculously high (like 600 miles to empty), and it constantly monitors the battery output at 14V. Help?? Thanks all

Fine to mix the oil, and you can leave it in until the next scheduled change.
 

The mileage range is based on gas consumption and fuel level. Is it possible that the gas gauge might be reading higher than it really might be? Meaning, it says 3/4, but it's really 1/2? You'll know by monitoring how many gallons you add when you fill. Just in case the fuel sending unit is going flaky (and reading higher than actual), I would keep 2 gallons of gas stashed in the trunk in the event you run out unexpectedly because you trusted the gauge. There is a sending unit in the tank that relays the fuel level back to the gauge. It's not uncommon for that sending unit to go bad.

Re: Fine to mix the oil, and you can leave it in until the next scheduled change.
 

Ah thanks that might be the problem. I did monitor it and it was showing 3/4 FULL after 210 miles of traveling (which would be awesome if correct). Also my evap-canister is clogged (have to hold the pump-nozzle halfway out for it to actually fill my tank with gas), think that has an effect on the gauge reading?

Newer SM-spec dino oils are much improved, the equal of "synthetic" from just a few years ago.

probably not...most likely just an issue with the sending unit

It doesn't hurt to keep an extra quart of whatever you're running in the spare tire well....