In May I will be going to Australia for 3 weeks and whereas I want to explore the red centre and the outback, my travel companion wants to see the east coast. We also have to make a round trip from Sydney to Sydney in the car - no domestic flights are possible due to the $1000 (and more) fee to leave/collect the car at Ayres Rock airport! I know that this is a a HUGE trip as i have been to Oz before, but is it possible?
So, this is our ideal itinerary...
Day 1, 2 & 3 - Arrive Sydney (1 night)
Day 4 - Drive to Blue mountains (1 night)
Day 5 - Drive to Byron Bay (1 night)
Day 6 - Drive to Noosa (1 night)
Day 7 - Fraser island (1 night)
Day 8 & 9 - Drive up to Whitsundays/Great Barrier Reef (2 nights) - Or maybe Airlie Beach/Great Keppel Island?
Day 10 - Drive west - stop somewhere in between Rockhampton and Mount Isa (1 night)
Day 11 - Drive to Mount Isa (1 night)
Day 12 - Drive towards Alice Springs (1night)
Day 13 - Drive to Alice Springs (1 night)
Day 14 & 15 - Drive to Ayres Rock (2 nights)
Day 16 - Drive south (1 night somewhere)
Day 17 - Drive south (1 night somewhere)
Day 18 - Drive to Adelaide (1 night)
Day 19 - Drive towards Sydney (1 night) - not sure where to stop yet
Day 20 - Drive to Sydney (1 night) - not sure where to stop
Day 21 - Depart Sydney
I would be really grateful for any feedback. I'm not looking to hang about on the beaches, this is more to see the country than to relax, but is this actually possible????

Wow! Just imagining all those hours spent in the car is painful. I hope you have plenty of things to do to entertain you on your drive. I spent over 6 weeks in Australia and didn't even cover as much territory as you, and I was going at a pretty whirlwind pace.
Yes, I suppose it's technically possible, but I still think you'd be mad to do this!
Why rent a car at all? Why not just use a combo of public transit and domestic flights? You can cut a few days' travel time out of your itinerary by flying from the east coast to Alice, for instance (save 3 days), then from Alice to Adelaide (save another 2 days), etc.

all you would see is the roads and a short view of some sites. you would be knackered from so much driving but it is physically possible.
flying would be better and probably work out cheaper then hiring a car
This sounds like a nightmare. You have far too much driving to do and not enough 'sightseeing' or relaxing. Everyday you are driving a fair distance.
A few years ago we drove from Mildura to Uluru. It took us a week, stopping off in Broken Hill, Flinders Ranges, Cooper Pedy, Alice and finally Uluru. The return trip took 24hrs of virtually non-stop driving, with the exception of lunch in Cooper Pedy and a couple of hours in Pt Augusta to drop a couple of girls at the Indian Pacific. Driving can be fun and you will get to see the scenery, even though it looks the same for hours on end, but you'll extremely tired at the end of the day.
If I was you, fly into Sydney and depart from Alice Springs, get a bus pass or some internal flights and forget the car. True, a car gives you independence but you're only following the bus route anyway.
ok Blue Mountains to Byron is approx 13 hours -so if you leave the next day at say 6am you will arrive at 7pm time to check in eat dinner and sleep. Is that your one day in Byron gone or was that your one day in the blue mountains?
Come fly with me lets fly lets fly away. Only way youre gonna get to see things remotely close to your itinerary is to fly. Why not take a few weeks exploring the east coast, fly to the rock return, then just kick back in Sydney with your pictures and memories and laugh and giggle while you plan your next trip. Much more enjoyable than getting a sore back from driving all day and a headache from not enough sleep.

Disregard the conservative alarmists above. You can do this and we want you to do it. I can see another bestseller in the fallout at the end of it all. An antipodean version of Fear and Loathing in Las Vegas. Sydney first up is a good move. Score as many uppers as you can get your hands on and sally forth into uncharted chemical mayhem. If you have the time please post regular progress updates. Good luck.

Thanks guys, I'm starting to get the picture :-) Ok, what about if we drive up the east coast, leave the car in Cairns and get a return flight to Ayres Rock? I'm guessing the trip back from Cairns would be just as gruelling though... Any ideas on how to experience a bit of driving in the outback without going all the way to Ayres Rock? (Taking into account we would be driving from Sydney to somewhere near the Whitsundays?