texas008

Over the weekend, a friend came over and performed the transmission service.
He's been in auto repair business for over 10 years and has the professional obd reading tools.

Feeling after the service:
The transmission feels smoother than before, the car feels more powerful. Definitely worth the efforts.

Nomenclature:
on the trans fluid pan there is a fluid overflow hole in the left middle of pan, and a drain hole in the corner
on the driver side of transmission there is a refill hole and refill plug (very hard to reach)

steps:
1. Jack up the car on four corners.
2. Drain fluid from the drain plug, the fluid is of dark red color, but not brown or black.
3. Drop the transmission fluid pan. The exhaust pipe bracket needs to be removed because it is in the way.
4. Clean the pan, the magnets, replace pan gasket,
5. Replace transmission filter, I use beck arnley filter, looks the same as the OE filter.
6. Bolt the pan back to the transmission. Plug overflow hole and drain hole.
7. Open the refill plug & refill hole on the driver side of transmission. they are very hard to reach.
8. Somehow could not fill by the side refill hole, then decided to use the bottom overflow hole, forgot to close the two refill holes on
the side. After a while, pan is full and fluid starts to flow out,
9. Plug in obd blue tooth transmitter, and pull up the transmission temperature info. on a tablet.
10. Start the engine, idle for a while and shift to D, transmission fluid splashed out from the two side refill holes.
11. Shut off the engine, plug up the two side refill holes
12. Start engine, shift to D, let the odo speed reach above 10 mph for a while and then let car idle. Continue to pump new fluid in from the overflow hole, When the temperature reading is between 45C to 55C, and when the fluid starts going out in light stream from overflow hole, plug overflow hole, all done.

Question:
1. Why did the trains fluid gush out from the two side holes, when shifting to D, would that cause damage to the transmission?
2. Where to get the obd blue tooth transmitter and the software that reads the transmission fluid temperature?

Lexuslsguy

There is need to service the transmission screen. In other words, don't drop the pan unless you need to actually service the unit. This holds true to the 400 & 430 as well. Drain and refill every 30k miles is the best preventive maintenance.

Doublebase

Unfortunately there is no screen on the LS460 , they went back to the traditional filter setup.

Kennyr44

Correct, paper filter thats made to be replaced like any other paper filter. Drain and fills of 3 Qts may be enough every 25 to 30k if started when the car was new.

texas008

This is the first transmission service for this LS460 with 75k miles.
There are quite some metal shavings on 3 magnets in the fluid pan.
If only drain & fill, probably 3.5 qt will come out; dropping the pan, probably 4.8 qt comes out. I've probably got ~ 5.3 qt out due to fluid gushing out of the refill holes.

Kennyr44

Now do another drain and fill and you should have pretty clean fluid.

texas008

Yes that's what i'm planning to do in the next few weeks,
it's just a bit of work, but not that hard, requiring some patience, probably on a similar level to bleeding brake fluid.
only 2 challenges i can see:
1. Temperature monitor: will use the jumper wire procedure, and also use a heat gun as backup,
2. Hard-to-reach Refill plug: will get a 24mm long wrench, or will just refill from overflow hole.

Determined to bring the transmission service down to a easy DIY task.

My friend who worked in the auto repair business mentioned that in the dealership, there is no time to check the transmission temperature, they just let car idle for 5 min and call that the right transmission temperature....

Kennyr44

These tricks of the trade are common in the world of flat rate service. For instance if you worked on one vehicle all the time and you clocked it as taking x amount of minutes to get the trans temp from cold to spec it would be pretty close to spot on. But doing different cars would not work. I do know that lots of trans shops don't measure temp settings when filling the new style no dip stick trannys. They say just getting the fluid hot is good enough to put the overflow plug back in and its correct. I know 5 minutes is not even close enough to get the temp up in my ML350. Shooting the laser thermostat at the fluid at the overflow hole as its trickling out works good. For the LS the fill hole is tight to get to even if you have the right wrench. The key is getting enough fluid in the fill hole before closing it and running the car. You don't want to have to go back to the fill hole with everything hot.

roadfrog

Temps are only part of the equation. As I recall, Techstream also opens and closes certain valves and solenoids in the valve body, ensuring proper fill. Thats why I don't mind spending 149 dollars to have my Toyota dealer do it.

Doublebase

The data link connector jumper wire procedure has a sequence where you shift the car through gears, most likely opening and closing the valves you mention. Whenever most cars have a transmission service that drops the pan and filter, most techs shift the transmissions through all the gears and reverse several times to push the fluid through the tranny. I have a friend who is a tech for Lexus and Kenny44 is right, he knows or guesstimates how long it'll take the fluid to reach temp without using any scan tool.

Ive done my tranny service three different ways now...once I changed the filter, gasket and cleaned the magnets. Used the DLC procedure, worked great. Once did a simple drain and fill and measured the amount out and in. Worked great. Once used a machine to pump fluid in and wasn't exactly sure if I put enough in...added a little more to be safe, didn't bother checking. Six months later I realized it was overfilled because it was leaking out of my pan gasket. Used a temp gun to measure temp, pulled the plug and about a half quart came out before it reached a light stream - that was a year and 30,000 miles ago. Never had a problem...even when I screwed it up. 144,000 miles and shifting great. Next time I may use a scan tool...just to try it.

zracer31

Thought I would chime in on another way to flush out all the old fluid with out a dedicated machine. I removed drain plug on pan and measured how much came out. Then dropped pan slowly and caught remaining fluid and measured it. Replaced gasket and filter, removed fill plug from drivers side of tranny and then added new fluid that equaled all that I took out. Now that there was fluid back in tranny, I disconnected the supply line from the transmission that runs into the bottom of the raditator, added a 1' length of clear hose and inserted it into an empty and clean old milk jug. I had a friend start the car (left it in park) and watched the tranny pump out 4 quarts of nasty near black fluid. Shut off car, reinstall 4 quarts of new fluid in tranny to replace what it pumped out. Repeated the same process two more times ( used 11 quarts total). At the end of the last time, the last 1/2 quart or so came out nice and bright red indicating all the old was flushed out. Reinstalled tranny line on radiator, followed the Lexus procedure exactly as many have done to set proper fluid level and called it DONE!

I have used the same process for all my cars and never had any issues - this is about as simple as it gets and costs nothing but about 10 - 15 minutes to do properly. This worked becuase the internal pump in tranny draws the fluid from the bottom of the pan, pumps it through the valve body, clutches etc then pushes it into the torque converter and then out to the cooler in the radiator and returns cooled fluid into pan to continue the cycle over and over again. By shutting car off after every 4 quarts of old fluid pumped out and adding 4 new qts into fill hole, the tranny "thinks" it is returning from cooler line and maintaining level in pan. It only takes about 15-20 seconds at an idle for the tranny to pump out 4 quarts.

roadfrog

Just playing devils advocate here and I think all this info is valuable. Soooo....if you drained a certain amount of fluid and then replaced that amount into the trans, you're assuming that the trans had the proper amount of fluid to begin with and wasn't short of fluid. In other words, your transmission may be under-filled? Am I wrong?

Chuckinnj

SIR, Your theory is correct! However, you are assuming that the fluid level was done properly by a Certified Lexus mechanic prior to the drain....... I would not trust that a NON Lexus/Toyota certified mechanic checked the temp and level properly WITHOUT using the Techstream.
IMHO: Doing this trans service is worth every penny going to the dealer to have done properly with a Techstream......... I would not do this service and I do a lot of my own maintenance. This is one service record that I would want to see that was done by the dealer "IF" I was purchasing a used LS.

roadfrog

That's exactly what I'm saying. That's why I had my Toyota dealer do this service for me. I'm a hardcore DIY'er, but I feel better leaving it to them. Especially for 150 bucks or so.

zracer31

FYI - To clarify my earlier post - I performed the magical jumper wire/shift through all the gears/sport to drive yada yada yada per the Lexus shop manual procedure to get the computer into the monitor temp mode. Worked like a champ, removed overflow plug from pan but NOTHING came out..........so in went about another 1/2 quart and then the fluid started a steady very light stream out the overflow. Reinstall that plug, reinstall the fill plug and all is good in the universe of LS transmission service.

To each his own, but this doesn't take a certified Lexus technician to accomplish. There is a reason this procedure was developed as an option to the Techstream - it works!

Also, I would like to take this opportunity and say THANK YOU to all who contribute and share their knowledge on CL, I have gained alot of insight and knowledge from searching/reading/applying what others have shared over the years