lenore

Time to get it diagnosed.  If you don't have that ability than you need to find a reputable shop.  If you do start with an ammeter between the negative cable and battery negative and measure the amount of currant that is drawing while everything is off.  than one by one remove fuses and see which one effects the currant draw. This will help you diagnose which system in the car is causing the currant drain.  Be aware that there is always a very small current drain for the security system.  But if you see a large drain (1 amp or larger ) than there might be a issue.

quick things to check are dome light, and cargo area light, they can draw a lot of juice if left on by mistake.

Sweet ride, welcome aboard.  I just bought a Toyota Solara convertible, I see so much resemblance.  

Welcome aboard, Hey it is a 27 year old car, but a great one.  Do a search on these forums and you will be rewarded with lots of help.  There are some very knowledgeable people on the LS400 on this site.  Hopefully they will chip in.

I would change it.  the Inhibiters in the coolant do break down.  USE only Toyota coolant, though expensive think of it as a long term insurance.  The coolant in Pink comes pre-mixed with water and is a matter of just filling.  Make sure the system is bled for air after filling.  I personally don't feel flushes are necessary on a vehicle that has only used the manufacturer coolant.  You will probably need two gallons minimum of the premixed. 

Wow one expensive brake master, I would look at a recycle yard

The belt can go easily to 125k miles, but 90k is the mark.  Totally agree have the water pump and idlers replaced.  The normal place to find replacement is a sticker on the front cam cover facing the top so you can see it.  If no sticker, than it may not have been done.  YOu can also set up a account with Vin # on MYLEXUS.  Sometimes there are maintenance entries if they had service done at LEXUS dealership.

Road trip....welcome aboard

here  it is:

I would get the valve stem seals replaced if they are the oil issue.  They should have been able to tell you where the problem was occurring.

The only issue I have heard of is the Gas tank plastic shield rattling against the body, easily fixed.  As for other shields maybe your exhaust hangers are stretched or some broken allowing too much movement.

They do make turbo's you will have to do the research.

Huge project requiring major changes.  First of all the LX470 is a rear wheel drive or 4 wheel drive with engine facing front to back not sideways like the RX300.  I don't believe you can do this within a reasonable budget.  Just find  another 3.0 V6 engine or rebuild. 

ON my RX's I chose KYB, been very happy with them...

Well I will keep everyone updated on my RX400h for the tire wear on Michelin Defenders.

Did the tires wear weird?   I have that tire on both my RX400h and my Ford F150 and they are way past 40k miles.  Did you get your alignment checked? 

I just re read your questions, and at 95k miles you are due for a timing belt change.  Many Toyota and independents can perform this for way less than the Lexus dealerships.  Other than that until you reach 125k miles your maintenance other than coolant change, oil changes, etc.  At 125 k the spark plugs are due.

The typical thing is to bounce the corner of the car and see how many times it takes to stop bouncing, over three is too much.  I have 203,000 miles on our vehicle and I changed the shocks because the car felt unstable on a curvy road.  Made a world of difference.  I used KYB shocks and also replaced the upper mounts. 

By the way the phone is on Android version 6.0.1

Ok I am out of ideas, my wifes Samsung Note 4 on Verizon network keeps disconnecting in the middle of calls.  I have tried  deleting all phones in her RX400h (Mark Levinson) and than re-installing her phone, seemed to work for a couple of days than back to phone calls dropping.  Does anybody else have similar problems with Samsung Note 4  on their vehicle?  I know Verizon has done a lot of updates on their software, but the phone is fine other than the blue-tooth hookup.  Any ideas?

Hate to tell you but the 400h gets best mileage in city and when going under 60 mph.  Best I have ever got on highway is 25.6

Personally I would be very cautious about a hybrid for towing....The components for the CVT and Hybrid system are very expensive.  I know some on the boards have towed.  I would certainly make sure to change CVT transmission fluids often if you do tow.  Also make sure the 400h you pick has the tow package.

The hybrid is a great vehicle, at around 100k on the 400h the timing belt needs to be changed.  Spark plugs at 125k miles. and I highly  suggest having the cvt transmission fluid change which is a drain and fill.  I bought mine at 89k miles and now have 203k miles.  The car consistently gets 24.7 with my wife's heavy foot.  Highway mileage the same.  Best mileage was 25.7 in California.   Brakes last forever.  I am on my second set replaced at 90k miles and they still have a lot of pad left.  Good luck with your search, I prefer mine (2008) as it was the last year of the 400h. 

I believe spark plugs are due. 

Wow that Celsior is gorgous...

Welcome aboard, and great set of wheels.