StlLexusTech

The vent for the differential is right above where the fluid is running down the aluminum plate on the back. If you look at the passenger side of the differential itself, you will see 2 recessed 10mm hexagon plugs. the top one is (obviously ) the fill plug, the other is the drain plug. The fluid should barely trickle out of the top hole when thre diff is full. If it doesnt, (and it probably needs to be changed anyway) drain it, get 3 pints of GL-5 diff oil and re-fill it. The "spray" of oil on the axles is from the side axle seals. kinda involved to replace.

the cooland in your '03 should be fine for 90k mi. thats why its called "LONG life". I work at a dealer, and we dont change the long life coolant until timing belt/water pump change at 90k. Yes there are drains on both sides of the block, they are 10mm. I wouldnt do anything with the coolant until 90k. It isnt necessary.

check the sunroof drains, if they clog, water will run down behind the "A" pillar trim inside the car. open the sunroof and pour a cup of water in each front corner of the sunroof track, in front of the wind deflector. It should drain out behind the front wheels...

Tap on the EGR valve and see if it changes. Like Steve said, they can stick. the valve should be fully closed at idle, otherwise its like a huge vacuum leak, and will cause rough idle conditions

LOL guys, once you've done 10 or 15 timing belt and water pump jobs on these things, you can do 'em with your eyes closed!! lol Dont forget to check the bearings in the idler pulleys too guys, ive seen some go bad and destroy the new belt!!!

Just wanted to say hello, and let you all know that I am a Lexus technician, I have 10+ years experience working on them. If I can help anyone with a question, please ask. If I dont know the answer off the top of my head, Ill try to find it for you.