I posted this on the RX300 forum also:

I have/had two vehicles with the V6 3.0L engine with a combined mileage of
201k. Did not experience any engine sludge or rear oil seal leaks so far (my Avalon has only 96k miles).

Does anyone know if and how Toyota solved the sludge problem? Does the 3.5L still run hot so that it will also be susceptible to rear oil seal failures?

I have owned nothing but Toyota cars since 1974. Here are the cars we have bought, all brand new (Corolla, Cressida, Tercel, 4Runner, LS400 and RX300). I never thought I would consider anything but a Toyota but, if I am objective, I must admit that Toyota has had more than their share of major quality issues.

Yesterday we looked at the Acura MDX and it is a whole lot more car than the RX350 for less money. I'm not sure I can bring myself to buy another Toyota. My wife definitely doesn't want one.

So, can anyone confirm that Toyota has eliminated the cause of engine sludge and premature rear oil seal failures? Thanks.

 

My first car was a '71 Toyota Corona. I've had many Toyota's since--Corolla, several Pickups, and several Camrys. I always had good luck with them and no sludge issues. I've also owned 2 Acura's (TL and MDX) and had good luck with them. I have since gone back to Toyota in the form of Lexus RX's (07 &'10). I found the Lexus to be in a whole different league in terms of quality of materials, fit and finish. YMMV

However, it seems to me that for you to be considering Toyota is senseless, since you say that your wife "definitely doesn't want one". Are you trying to start WW III?

 

I know nothing about the seal problem, however I think the sludge problem was solved very easily.
I think the sludge problem was solved by telling people to change their oil. Some people never changed it, and the oil was turning to sludge. I had a 1998 Avalon and received a letter to change the oil on a regular bases, which I think was 5K miles.

I've not heard of a sludge problem in recent years in any model vehicle.