I am the original owner of a 2008 Lexus LS460 with 147k on the clock (mostly highway.) The transmission fluid has never been changed but continues to work with no issues. Should I leave it alone or do a drain and refill to avoid future issues? I would never do a flush. A Toyota tech told me to leave it alone since I did not change it at 60K. What do you think? Thanks.
Depemds on the curiosity factor to me.....if curious...I would drain the pan...drain into clean pan...Check the amount of residue on the oil pan to see how much wear has shown up...Clean the residue from within the pan. Button it back up and refill with what you drained. Other than cleaning the bottom of pan..nothing has changed.
Another is don't clean the pan...just inspect to see how much residue is present. Then slam dunk it back on. Refill using old fluid.
The deal is IF YOU changed the fluid..well...its probably that the trans will now experience slippage now that it did not before when its cold like so many other complaints have been posted here lately...unless your in a local thats NOT COLD.
Remember that this is an experienced prediction...not necessarily a 100% probability...
I would drain and refill the fluid.
If it helps, I have a 2012 LS460 AWD with 138K miles. I just flushed it with no problems. When people talk about changing the transmission fluid they use terms with different meanings. Usually when they say "flush", they mean use a tool that applies pressure to move the fluid in and out.
However, when I use flush, I mean drain and refill manually (multiple times until your fluid is like 98% changed out) - no pressurized tool.
The latter is what I performed. It took roughly 5 drain and fills to get the fluid to be much newer. After the 4th drain and fill, that's when I also dropped the pan and replaced the transmission filter and gasket and put in the final amount of transmission fluid. (That way the new filter was filtering almost exclusively clean transmission fluid.
Note, when you drop the pan is when you'll get a good look at the metal on the magnets. For 138K miles, I was pleasantly surprised how little debris was there - there was some, but it was very clean.
The fluid I drained was BLACK. Over the 5 flushes it became much more red as you'd expect. You'll want to get a pump so you can easily pump the 2.5 to 4.5 Liters of fluid in at a time. You won't get a funnel in there. There are 2 videos I used to muster up the courage to do the job. These 2:
https://www.youtube.com/watch?v=6dKEMI_YFrQ&t=169s
https://www.youtube.com/watch?v=ej_6BZpK3gg&t=666s
Also, you'll need to buy the transmission gasket and filter/screen from Lexus - I went to ebay and bought from a lexus dealer (on ebay) at a good discount.
Also, there's LOTs of disagreement on various lexus boards regarding what fluid to use. If you're not sure, use the genuine toyota WS (World Standard) fluid. I personally used the Valvoline MAXLIFE ATF - much cheaper and WS qualified. Good luck! 😎
