Hey there guys. I have an 04 SC430 that has just over 200k miles on it. I bought it from the original owner that always had it serviced at a Lexus dealer. It had 170k when I bought it. I don’t know if the trans fluid has ever been changed. Lexus website obly says stuff about timing belt, water pump, spark plugs, etc. The transmission shifts perfectly and is very smooth. Should I do a Drain and fill, flush, or leave it alone? I pulled the dipstick out and the fluid was maroonish red to a light brown in color. Any help would be appreciated.

 

Don’t worry about the filter, the can last forever. The best method I have found is to disconnect the trans cooler lines at the radiator and determine which is outflow and which is the return. I believe the straight one will be your output, the angled one will be the return but you’ll want to verify that. Then get about 3 gallons of Toyota Type IV, again, verify for your year to make certain. Then get an empty jug that holds at least 1 gal, more would be better.
Now what we are doing is collecting the fluid that exits the trans and catch it in your empty jug and insert the other side into the fresh gallon. When you start the car, it’ll drain old fluid and pick up fresh flui from the return line. After the new jug is empty the old one should be full,turn the car off amd u can just move the empty one to the collection. And keep doing this til your getting new fluid exiting the output side.
This is an easy method to replace all the fluid from your trans and not damage anything by forcing fluid through like they do when flushing it.
I recommend doing this every 45k miles and use the recommended Toyota ATF, anything else regardless of their claims, could cause a critical malfunction.

 

okay Thanks for the input. So I shouldn’t worry about people saying that the trans will start slipping because of the the high mileage and the possibility of it never being changed before?

 

You sure about, "and insert the other side into the fresh gallon. When you start the car, it’ll drain old fluid and pick up fresh flui from the return line"?

I have never seen it work like this, not saying can't just not my experience. "Normal" procedure would be run engine to collect a quart or so using the line that has fluid exiting, turn off the engine, and then replace the same amount of new fluid back into the trans -- repeat until fluid runs clean.

 

That doesn't work (at least for me), the pump can't draw fluid back into the transmission fast enough I've tried what ends up happening is the fluid flow stops. Either way I used to run the engine to pump fluid out don't do that anymore it doesn't get that much more out anyway.

Do a drain/fill and repeat as much as needed to freshen the fluid. On the filter it is the strainer type so generally it doesn't need to be replace but I have seen them get gunked up pretty badly on neglected transmissions.

 

I have a GS400, so not the identical vehicle, but pretty close. My return line was not long enough to submerge deep into the fresh gallon, and suck it out. So I had to insert a funnel into the end of the line and then I pour it in from the top, so I had a gravity assist. But it worked out fine. My apologies for suggesting this method if it isn’t viable.

 

No need to apologize. Next time I'm going to try the gravity assist both my containers were below the cooler lines.

 

i will do that next week, will pump it out of one side and pour it in thru the dipstick tube

 

Just refill using the proper refill area of the transmission…not the dipstick tube.

 

Proper refill area is under the car, and you can not drain all and refill after with car running.

 

I think I read your post on Facebook on this topic. Lots of different opinions....
You'll see that here too but this group has the experience actually doing what they suggest. Check out https://www.clublexus.com/forums/sc4...rain-plug.html

I would still just do a drain from the drain plug and refill what comes out. Different vehicle and transmission but that was the Lexus recommendation for my RX300 and it worked for me.

 

You got a 04MY so just drain and refill a couple of quarts for like 3-4 times during the next several weeks. It's faster than your regular oil change.

 

You can Watch this video and then decide if you want to change the fluid

Otherwise the link 2 posts up was how I did it

 

Here's a thought take it to a Lexus dealership and ask them to drain the transmission fluid. You got 200k out of the first batch so you should be able to pop for a new batch? You do not want to do a flush as all kinds of krud could break loose and jack up the transmission. Do a drain, drop the pain and put in a new filter and call it good. Just my thoughts. That is what I did on my 1990 Ford Bronco II with 140K on the clock a couple months ago. No Issues.

Dennis

 

The easiest is to do one drain and refill + then use an electric or hand pump to pump out the fluid and refill 3x ~ 5x.

A more involved method is to do one drain and refill + disconnect the trans cooler lines and use the two-bucket method: One bucket filled with refresh fluid for the return line and one empty bucket for the other line + fill to level.

Important to note that the fluid should be, IMHO, at the notch at cold start. Do not under fill this transmission. You risk burning the clutches.