Hyundai Repair: Oil loss, high speed motor, hyundai lantra

Question
Hi yeah the car has done 45,000 miles, i've had the car for 40 days now, brought it from a Hyundai dealer 200 miles away, its under warranty but you know what those things are like, only certain things are covered and diagnossis definately isn't covered, iv'e done about two thousand miles in the time i've had it, i did actually notice the oil wasn't fully topped up when i drove it home when i first brought it(and it was supposed to have been given a full pre sale service), it would seem the high speed motor way distance driving is where the oil is being lost, because i didn't really notice it drop before my long journey vacation the other day.
-------------------------

Followup To

Question -
Hi i have a 1999 hyundai lantra 1.6 gsi manual with 47,000 miles genuine! and i have just noticed my oil level was at minimum on the dip stick i can't see any oil on my driveway at home and it doesn't seem to be burning any, i've just done a fairly long motorway journey of about 400 miles where i whent a way for a few days, i get back check the level and as i say it was at minimum, any ideas?

Answer -
First, you should have a good look at the exterior of the engine, both over and under the vehicle.  Some oil leaks occur only when driving, so not having any on the driveway isn't necessarily an indicator.  Additionally, some leaks are small enough that the oil tends to soak into the dirt on the engine rather than drip.  

Second, it's important to know how many miles the vehicle has been driven since the oil was last topped off.  Also, was this at a shop, or did you top it off or witness the oil being topped (i.e. do you know for sure it was full)?

And third, it appears you're not in the U.S.-- you referred to the car as a "lantra"-- but reported the odometer reading in miles.  The distance you've driven since the oil was topped will be important here, so I mostly want to be clear that we're talking about miles and not kilometers.  Either is okay, but for this problem I'll need to be sure which one we're using.

Answer
So far, there's nothing here to cause alarm.  By your accounting, you've lost less than a quart of oil (from less than full to the low mark) in 2000 miles.  The industry standard is 1 quart in 1000 miles for most automakers.  While I don't personally agree with this, I do think one quart in 2000 miles is reasonable.

Since you believe the oil loss to have occurred primarily over a short distance, I'd recommend checking the oil every time you refuel until you get a feel for how much oil the car is using.  

But if you've got no leaks, and your consumption is less than 1 quart in 1000 miles, your chances of getting warranty repairs are very low.