Automatic Transmission Fluid

[GEN]

Hi!

Does someone know the procedure for checking the automatic transmission fluid? (on a 98 LS400) Is it done hot or cold? I'd be most grateful for any info.

Thank you.

[steve2006]

Hi,

This information should be in your driver's handbook but here goes,

It is recommended that the transmission fluid should be checked when hot ( to be the correct temperature in our current weather a 15 mile drive will suffice)

With the engine running at idle take the transmission slowly from Park through all the positions then return to park.

With the engine still running ( take care here) pull out the dipstick, wipe it on lint free cloth, reinsert then pull out again to check the level.

There are 2 sets of marks on the dipstich Hot and cold so use the hot range to determine the level.

The cold level is only a rough indication and not as accurate as the hot reading.

If you need to add fluid use a funnel and pour down the dipstick tube.

If the fluid colour is black or smells burnt replace the fluid it should look cherry red in colour if ok.

Use only Toyota Type IV fluid as replacement.

[runsgrateasanut]

Reviving a somewhat old thread. I always find checking Trannie level is a nightmare. I had the car up to temp this morning and then left it a short while no more than twenty minutes. Started and put through the gears and back to park. Tried this several times checking the fluid level and its never consistent. It was the same for me with the Mercedes. You see fluid on both cold and hot but nothing in between and so on.

I don't know that I'm loosing any, but the car is getting a bit clunky going into reverse and certainly at start up. Colour looks good.but I have added a cupful hoping to improve the smoothness. Drives smoothly enough.

Confess that after the Transmission/radiator fail on the Merc I was putting fluid in and taking it out again by tube, quite a few times. Car is still on the road with someone else (no advisories last MOT Ouch!) but I wish I could feel certain I haven't now overfilled.

Two options I suppose. Either let a mechanic check and hope he knows what he's doing or have a complete drain and refill. Not something I'd like to attempt with fluid in the Torque Converter as well as the sump to contend with.

[Malc]

......... my indy just always checks this fluid level and quality ( by sight and smell ) at every service and has done this for each of my Ls400's over the years.

Never had to top-up or replace at any time to my knowledge.

If you're unsure then just let your servicing guy take the strain, he probably wouldn't even charge for a 10 second job ( checking that is )

Malc

[steve2006]

Unlike Mercedes there is no drain plug for the torque convertor on a Lexus so it's a case of either drain and replace 2ltrs at a time via the sump or remove the cooler pipe pump some out and then replace with the same quantity.

I think there's a tutorial for both on www.lexls.com.

It is recommended in the owner's manual that the car is driven for an extended period to ensure the fluid is a full operating temperature and properly circulated within the transmission to ensure a correct hot reading,letting the car idle for 20 minutes may not acheive the same result.

The process I have detailed previously also needs to be done in a timely manner again to ensure accuracy.

[runsgrateasanut]

Thanks Malc - you are probably right. Steve I didn't leave it running for 20 mins but after a ten mile drive I leftit to settle for 20 mins. Though I read that this was the procedure.

Question is, with a car done over 115k miles, would you find when you start the car from cold and select reverse that there is likely to be a bit of a clunk (or jolt should I say) as it engages? Is this normal or should it be as smooth as silk.?

(I should add Malc that you would need take the car for a long drive beofre going to the Garage as they can't check it hot just by letting it stand and idle on the forwcourt., so means they have to tkae it for a drive. Would they want to bother or just check it cold)

Edited February 17, 2015 by runsgrateasanut

[SHELLDRAKE]

Stuart: I always press the brake pedal before putting it into gear, this stops the car from jolting "R or D" otherwise the jolt will happen.Mine has 160k on the clock don't worry about the mileage (as smooth as silk)

[runsgrateasanut]

Thats good to know Norm. Used to have similar in the S Class. Just been wondering if level may drop over the years (21) with some form of evaporation, that is assuming its not been checked or changed in its history, which I can't say. There's no leak which is the most important consoideration.

[Malc]

..... Stuart hi, I've probably driven around 200k in my Ls 400s over the years and haven't ever concerned myself that the gearbox fluids are other than ok !

That's why I take it to my indy to service once a year with the MOT and just about get superb and trouble free motoring ( don't much like visiting the tyre sales place tho', it's ALWAYS expensive it seems )

Malc

[runsgrateasanut]

Just a thought, Can you actually engage the gears without the foot on the brake? I have always done this and so never cheeked but thought it was a safety thing on most auto's?

Just taken out the small amount of t/fluid I added and although the colour might loook nice and cherry red on the stick it sure isn't that colour once you get some out into a jar. Much darker. Hopefully not disturbed any silt if there is an that gathers around the filter. I'll get my mechnic to check it when he gets the chance - got so many things to do, wishbones front and back, rear springs, exhaust leak. Tutch I'm going to be borassic lint as they say down south, at this rate.

[cruisermark]

hi

in the mark 3,4 and 430 you can't