Welcome!

 

I was not aware that Edmunds had this excellent maintenance information on their site. The TSB listings are especially useful.

 

I just found out what should be done after not getting any straight answers from my oil change place. every 15K if you tow vigorously but if you don't then at 30K you should have it changed to remove all the metal shavings etc from being broken in. After the 30K service you should then be good up to over 100K (using synthetic of course). It is going to cost me $90 for the front and $90 for the rear. This included removing flushing and adding new synthetic gear oil.

Hope this helps. I knew every 15K was way too often so I quit going to that service center.

My situation is that I am changing it for the first time at 50K due to the vehicle not even being 2 yrs old and it is all highway no towing miles. Then again I just found out the right answer for this question. I would have done it a bit earlier if I had this information handy.

 

on newer Lexus [and many other mf] uses synthetic on both axle and trans hence no change interval recommendation on owners manual. about two+ years ago i went to the dealer to get trans flush on past 05LS w/50k on ODO and they suggested i skip it. i sold the LS to my brother who now has over 100k with new T-belt recently done at the dealer still not suggesting t-flush. Only t-flush I did was on my old 96SC400 at 100k and dealer looked puzzled when I demanded t-flush. I have a friend who totalled his 90LS400 few months back with 230k on original t-fluid that ran great before the crash. i would not worry about t-fluid unless RX is use for towing something heavy.

 

Any DIY for the rear dif and transfer case? Been searching for a service manual, but can't seem to find one.

 

i would be careful about the flushing. There are a number of posts on the RX 300 FORUM warning against flushing the transmission. Don't know if it applies to differentials. I am not a mechanic.

 

Do you have differentials filled with oil on the 450h?