2014 Lexus ls 460 AWD Trans Fluid Change

[srgilbert]

I've seen a number of ways to handle this one but thought I would throw this out.  Would it be OK to simply drop the 2+ quarts via the pan plug, refill the same amount and then do this again 2 or 3 times to swap out perhaps half the trans fluid?  LS 460 has 55K miles so there should be little risk I would assume.  No leaks.  I've also seen via the trans cooling lines but that seems more challenging.

 

Thanks!

[Steve]

I believe the transmission requires the car to run to temperature as the fluid heats up and expands. you will be there for ages messing around and best just doing the job fully and also replace the filter at the same time. I know when we dropped my transmissions sump there was slight sludging at the bottom too. So best just do the job then adding cold fluid, warming up to a specific temprature and dropping out the excess. and keep going back over and over. It will also invlove you connecting a OBD reader to get the temprature. exactly before dropping excess fluid.

I think doing it properly is the easiest way. took us about 90 mins.

Lexus do provide a workshop tech notes about how to change this properly. Best to stick to this to get it right.

Be careful what you see on youtube. 
 

[srgilbert]

Appreciate the feedback - yes replacing the filter/gasket makes sense as is cleaning the sludge.  I am having some 2 to 1 downshift harshness at time - hopefully this will help.  Fluid is about 10 years old but only 50K miles.

[dstrz]

@srgilbert I too am experiencing some 3-2 and 2-1 downshift harshness on a 2014. I’m curious if you were able to get the fluid exchanged, what method you ended up using, and if it resolved your issue.

[srgilbert]

Well I have the supplies but have not performed the change yet.  I have had the battery disconnected a couple times and that seemed to help for a while - no idea why.  Checking with Lexus the transmission has the latest software.

[srgilbert]

Finally did the transmission strainer and 6 quart exchange of transmission fluid.  The greatest challenge was to get access to the front 2 pan bolts due to the transmission support.  Managed to get a 10mm open wrench on them and slowly got them out.  About 2 months ago the battery went bad so the transmission was rebooted and that helped the smoothness of shifting.  The 6 quart flushed helped a bit more.  I set the reminder for another 30K and wont be as fearful next time