Iluvlexus

OK. Finally did it. Was quite easy with excellent access to the drain and fill plugs..Neither fluid was particularly bad with the CVT darker than the rear. Only issue was the CVT must have had 6 quarts in it. I opened up the fill plug and it came pouring out. Wonder why it was so full? As other have noted, the CVT took 4 quarts and the rear 2. Thanks to all for your help.
Scott

thomas1

good job. What was your mileage?

Iluvlexus

Sorry, meant to state that. 97K. My fluid appeared much cleaner than yours. Anyone else note that the factory fill is quite generous?

MeryLexmas

If I were to drain it, I would put it into a container where I could measure how much came out. It would suck to have 6qts come out and only be able to replace 4. If Lexus considers it lifetime fluid, there is a chance that you may not be able to put in as much fluid as they put in originally during assembly.

thomas1

Here is my latest tranny fluid comparison after 18k miles at 129 total k on vehicle....note dirty fluid on left.....That is from driving hard to LA/Sacramento many times...at 80plus mph.

retiredguy

Rule #1 is to always....ALWAYS crack open the fill plug BEFORE opening the lower drain plug. That way you know that you will be able to replace the fluid. I've seen many times people open the drain plug, drain the fluid only to find out the fill plug is frozen shut.

kwanyu

Thanks for the great writeup guys. Took me 30 minutes to do both front CVT fluid and rear diff fluid on my 130,000 mile 2006 RX400h.

Fluids were fairly dark for me. And I want to say the car feels a lot smoother but I'm sure it is just in my head.

I'd highly recommend a decent sized wrench, along with a lot of rags for the job, and an extra quart of oil nearby.

thomas1

Your welcome....Glad it went so smooth, my old bones are moving slower, maybe you should do mine for me again, it is due in 500 miles.

spacecraft

One question for those who already did the job:
What about the CVT oil radiator behind the bottom of the front bumper, on the driver side?
Is there a way to drain it also, or did you just accept to leave some old oil in the circuit?

thomas1

I just elected to drain and fill, seems to clean up everything quite well. After two changes the fluid was great looking.

spacecraft

Thanks for your feedback.
I just realized that this matter is not specific to the 400h, so I thought to follow up on the "Transfer Case and Differential Oil" thread, in the generic RX 2nd gen section.
Thanks in advance to anyone who has further thoughts on this topic for following up on that thread, just to avoid splitting the same discussion...

https://www.clublexus.com/forums/8494980-post34.html

kwanyu

I don't know if I have the oil cooler radiator, but it does look like I have two radiators. I had assumed it has something to do with the hybrid cooling but maybe it was for the tow package (I have a hitch but I never used it).

Either way, even if you have the oil cooler radiator, wouldn't a second drain/fill essentially just clean the majority of the oil assuming the oil circulates properly?

jimboesfo

I don't think that a second drain and fill would be worthwhile.

From the owner’s manual for transmission drain and fill capacities:
3.9 qts without tow package
4.1 qts with tow package

The service data sheet (thanks maseace) indicates 4.4 qts. I assume that this is the total system capacity. So it would appear that at most only 0.5 qts (about 10%) might remain in the system after a drain and fill.

thomas1

Yes what I did the first time was wait a 1000 miles and then do the second change. This was because I bought the vehicle with 87k miles and the fluid was really brown. After the second change the fluid was a bright red.

maximizese

I'm preparing to do a CVT fluid change and was wondering how you all pour the fluid into the fill hole. Can this be down topside from the engine bay with a flexible funnel or do I need to use a siphon/vacuum pump from underneath?