Bill Dowd

I started using mobil one snythetic fluids trans motor power steering and rear end since 1986 put 529,000 miles on a 1986 Toyota cressida using all mobil one fluids and every thing was original now my 1991 Lexus ls 400 with 297,000 has been using all mobil one fluids trans motor power steering and rear end and no problems. I plan to run to the car to 400,000 and sell it. if your are going to use regular trans fluid like the man said above use the Toyota type 4 and drop the trrans pan and look for any metal if none clean the screen and go about your merry way the trans will last 300-500,000 miles using type 4 or mobil one snythetic the secret is to change it every 25,000 drain the pan from the drain plug in the trans pan. also look between the radiator and the air condition condensor to make sure no junk has gotten in there it will clog up the air way for the radiator and cause the engine and trans to run hot. I put a big trans cooler on my 91 so far no problems in the hot So Cal weather which includes trips to Palm Springs at 117 degrees and some times sitting in traffic at 117degrees for hours at a time and the old lexus just keeps rolling along.

DesertLS

I was finally able to drain some of my transmission fluid after it kept on reading that it was overfilled. I drained about 1.5 quarts so I was sure I wouldn't have to disconnect the hose again to drain more.

After draining the 1.5 quarts, it was reading at the "C" level with the engine at operating temps. I kept filling and checking, filling and checking, adding about 0.5-0.75 quarts total until the reading was in the "HOT" level.

The pic is the final reading at operating temp. I'm going to check again today after running some errands. It seems good to me. What do you guys think of the level?

python

iTrader: (4)

add another half pint or so

Yamae

I had a similar experience. The cold level was barely touching the LOW end of the gauge at 15 degrees C but after driving 40km, the level was about 3mm higher than the high end of HOT marker.

So I decided to drain some. I drained about 0.1L and the hot level was a bit lower than the high end of HOT marker but when cold, the gauge did not get any. I mean I could not see any red part at all.

I added 0.05L but still the gauge did not reach the surface of ATF but after 40Km of drive, the hot level is just the high end of HOT marker.

The symptom is something common among other Celsior owners here. I just wonder why?
Is it because of the accuracy of the gauge not enough?
Does Toyota ATF Type IV increase the volume more than Type II?

RA40

iTrader: (6)

That gauge is not well calibrated. On the original, that ferrule would slide up and down so I had no real idea what was "proper" tranny fluid level. I bought a new one and like Yamae has stated, it has varying results on hot-cold checks.

I just tried to get it matched up this last time and with the cold level accurate, it does not go into gear. It took .5l more and now it reads overfilled when hot. As far as what I have encountered, it is less tolerant of underfilled levels.

LScowboyLS

I, too, have noticed that this transmission cannot decide whether it is over or under filled

DesertLS

Well it sounds like I'm not the only one with this issue. When I did the original fluid exchange, I filled 0.5 quarts less than I drained so I could make sure it got the accurate level. After getting the engine to operating temp it still seemed overfilled. When I drained and refilled some this weekend I netted another 0.5 quarts less for a total of 1 quart less since before the fluid exchange (still able to follow me?).

After running some errands yesterday, I checked the level and now it reads overfilled!!! It sounds like no one is able to get an accurate read so I'm probably going to add 1 quart back to get it to the same level before I did the fluid exchange and probably the level from the factory.

By the way, I'm pretty sure it was the original fluid as the auto part store rep where I recycled the fluid had to ask me again if I was sure it was transmission fluid. It was the dirtiest fluid she had ever seen. It is a 99 with 85k (I got it at 83k), so I'm guessing it had never been changed (previous owner ). Better late than never!

LScowboyLS

I spoke to my friend who is an engineer for Aisin - he said that there is some thermal expansion difference between the original Dexron III and T-IV which would cause the dipstick to not make as much sense.

he also said that on these LS400 transmissions, A340E, A341E, and A650E, that it is much better to have a pint (0.5 liter) too much fluid rather than too little

he said that these RWD Aisin transmission models are not truly overfilled in such a way that will cause any problem, until it is overfilled to the point that the fluid gets foamy or frothy (aerated)

PureDrifter

iTrader: (10)

does your friend have a title...?

If he's not willing to post up here himself (preferably with his title and posting) then it's just hearsay.

Any other factual evidence would be fine too. ie-chemical analysis of t-ii v. t-iv Indicating a difference in expansion rates.

sam12345

iTrader: (1)

There are two lines and hash marks between the two lines with the word hot on it. That means that anywhere between the two lines is ok. It also means that the lexus engineers designed the transmission to operate between the two lines otherwise it would make no sense to put those two lines it woul only have one line. Therefore comment 422 is ok and it should be left that way. Furthermore it makes sense to put it in the center of those two line since the transmission may operate hotter or colder than what it was when measured so you have a margin of error either way.

RA40

iTrader: (6)

I'll go with that. Just tell our LS400 to be there.

sam12345

iTrader: (1)

The one that matters is the hot check.

From the Lexus manual. http://drivers.lexus.com/t3Portal/do...df/6-3_192.pdf

CHECKING AUTOMATIC
TRANSMISSION FLUID
1. Check the fluid level only when the transmission is at normal operating temperature. With the vehicle level, first set the parking brake and then start the engine. While the engine is idling, depress the brake pedal and shift the selector level into each range from “P” to “L” and return to “P”.
If the vehicle has been driven over 16 km or 10 miles (24 km or 15 miles in frigid temperatures) and the fluid temperature is 70_C − 80_C (160_F − 175_F), the transmission is at normal operating temperature.
You may check the level when the transmission is cold. If the vehicle has not been driven for over five hours and the fluid is about room temperature 20_C − 30_C (70_F − 85_F), the transmission is cold.
However, checking a cold transmission is to be used for your reference only and the transmission must be checked again for correct level at normal operating temperature.
If the vehicle has just been driven for a long time at high speed, in city traffic in hot weather, or the vehicle has been pulling a trailer, an accurate fluid level cannot be obtained. Check the level after the fluid has cooled down (about 30 minutes.)

sam12345

iTrader: (1)

From the Lexus owners manual

c. Pull the dipstick out and look at the fluid level. If the transmission is cold, the level should be in the “COOL” range on the dipstick. Similarly, if it is normal operating temperature, the fluid level should be in the “HOT” range. If the level is at the low side of either range, add automatic transmission fluid type T-II or equivalent to bring the level within the range. (Fluid is added through the dipstick tube, using a funnel.)
d. While checking the fluid level, also check the condition. If the fluid is black or if it smells burnt, have it changed.
e. After checking, return the dipstick to lock position.
CAUTION:
When the engine is running, keep hands and clothing away from the moving fan and the engine drive belt.

NOTICE:
Avoid overfilling, or the transmission could be damaged.

http://drivers.lexus.com/t3Portal/do...df/6-3_192.pdf

ls400geek

This is really interesting because I experienced the same exact thing. I raised my car up on an driveway incline and got a little over 3 quarts out of the transmission on my drain. It also took about 1/2 hour for that much to come out as it dripped out fairly slowly after 2 quarts or so.

ls400geek

Interesting, 3 quarts came out on my drain, and I added 3 quarts back -- it's at the full line (and after checking it several times on a level surface going up and down through the shift cycles several times). I drove it for over 1/2 hour and checked it again and it was at the full line.

I should note that (as mentioned in my post on this thread) I did a drain/fill on an incline (over 30 mins).