Tomorrow i am going to service the transmission and engine "ignoring codes" new filter new transmission fluid engine oil and filters for both. I noticed ticking noises last few days then the start of bad shifting into 4th. So i must service it right now or kill the car. I have had 2 full rebuilds over time i have owned car so i know these signs and i would destroy the box in a couple of weeks from now if keep driving. These posts here are common mainly after "this event" and it is too late to fix. I already added a cooler under fender but going to drop the sump and look at this burnt oil tomorrow and see how dark it is. Then pan for steel. I have a few big magnets next to me i will add to the sump tomorrow., Have loads to do to car eg have two radios to fit so will see what i am motivated to do after i finish it. "Ignoring codes" the same two codes everyone has and changed those sensors like 3 times as well as every plug coil more than twice and codes go off on same points of road that i can predict the moment it first happens of a day Uphill same point misfires wondering really that it has to do with effects it with tailshaft and amount of play in it. Sounds odd but that is another variable of movement which computer doesn't allow for. How different is the drivetrain between model rx330 etc as going to probably fix it like we do. Just documenting this in case it saves your rx300 this week from dying.

 

How is the air flow on the cooler? Any obstructions?

The fluid only heats up when it is providing the slip, vehicle stopped, and vehicle during shifts. Are you doing long stops (gear engaged) and lot of stop and go traffic. If you get a good bit of highway driving in-between, the torque convertor should be in lock (no-slip). You should get a CEL code for converter failing to lock.

I understand that you can't change the driving environment but worth giving it a thought as to why the problem keeps coming back.

Talking about magnets, they need to be at a certain position based on the way the fluid runs down (gravity-based). So make sure they are where the factory suggests. You can always try to do more, but an understanding about fluid flow would help. The sad part is that the magnets only hold on to things that can be magnetized and aluminum and certain alloys don't get removed from circulation.

If you go the path of rebuild, make sure you get the upgraded planetary gears. Also check the pump tolerance if you suspect fluid flow as an issue. The art of engineering is to balance all things and adding axially cooler may be a good idea for temperature control, but it can stress out the pump. I am not saying this is what happened, but with sale volumes in hundred of thousands, the engineer are no longer over designing sub-modules. I keep reminding folks that back in 90's the gold standard was 100K miles for auto trans.

Salim

PS: Just realized you are in Australia and the ambient temp can be high too.

 

I had my second rebuild only about a year or two ago so hoping i am not going to be spending on a 3rd rebuild. I have been sitting in traffic. Anyway done the service today and will see how it behaves this week. i did it twice today as forgot to add the magnets and pan wasn't as dirty as previous services.

 

I have a 2001 RX300 with 193,000 miles I had the trans rebuilt at 155,000 miles and haven't any problems. I use Max Life synthetic trans fluid change it every 20,000 miles I put a thin Hayden trans cooler in front of the AC condenser.
I also use the Max Life in my power steering and it really works well, I am in lots of traffic here in So Cal with the heat and no problems. I have always used synthetic fluid since 1986 in all of my cars some going over 500,000 miles.
And never had problems with the transmissions, the only reason I had problems with the RX300, I bought it used and the tranny was bad the planetary gears let go. On this tranny the planetary are welded and hardened. So I will se how long
this tranny last. I use Mobil 1 extended service in the motor change it at 10,000 miles or one year did this on all my cars, and no problems even at 500,000 miles on my 86 Cressida. Synthetic oil far exceed regular oils in my book.
Toyota and Lexus new vehicles should last at least 300,000 miles plus they are now running full synthetic fluids in the motors and transmission's.

 

My transmission is fine. I did however have all these symtoms and turned out cheap air fillter clogged up in weeks and that combined with my services have fixed issue.

 

Did you get the trans serviced and what happened.

 

I dropped pan and took out filter replaced it added magnets i pulled out air box and put it back with another filter which wasn't old but clogged but i do drive over a dirt road each day and will change that again to k&n filter as it makes a huge difference. I bought air filters for $8 and $80 and one is 10 x better.
Dropped oil also and changed filter all synthetic. K&N oil filter too as well as air filter. And took it to a friend to get a reboot on computer.

 

I am still runing one of these $8 air filters a new one and you can know there is no flow under load eg giving it a bit up hill sudden stop then back on gas it works like a plastic bag and it is 2 days old. I will go back to the perfomance air filter next few days and give up entirely on cheap but was using them up. Other thing is if ever find a source for mesh transmission filters not geo fabrics as far better flow let us know. I been driving mellow and if not giving it a bit but finding these filters are so rubbish if you decide to suck some air.