How long should I go on these??
 

I just completed an oil/filter, rear end, tranny fluid change. I used Amsoil full synthetic 10/40, Amsoil filter, Type IV tranny fluid(2qts), and Amsoil full synthetic 75/90 Gear oil in the rearend.I currently have 30,000 miles on my 00GS400. I plan on changing the oil at 5000 mile intervals from here on out with synthetic along with a drain and fill on the tranny.
I was told that the Rearend should be done for the life of the car, is this true?
By the way I took my car to Jiffy Lube with all of my stuff 30 minutes before they closed and offered them $20 to do the labor off the books. They did it. It's not worth $20 for me too put my car up on jacks.
Thanks,
Dean

My service book has the factory drain interval for the differentail and tranny at 60K miles.

Different thoughts on the tranny drain. <shrug> Mine was fully flushed at the dealer at 58K so I'm going to do the 2 QT drain every 10K miles.

Did you replace the brake fluid? My factory brochure has this at 30K miles.