vuvu

Could anyone confirms that when check the level of transmission fluid, do I need to put the engine in IDLE mode ? or the engine is OFF.

For the past 2 years, I filled out the transmission fluid and check the level when the engine is IDLE. The tranny shift very rough until the recenlty. I changed the tranny fluid and decided to fill and check the level with the engine is OFF, which I filled the fluid less than before. And now the tranny shifts very very smooth.

So what method is correct? Check level of the tranny fluid with the engine is ON or OFF?

Thanks.

ruki400

You check it when the engine is off, it has a fill level on the dip stick for both cold and hot (running temp).

London Bill

If I may just amend a tiny error in the last post by "ruki400",

YOU CHECK THE TRANS FLUID WITH ENGINE RUNNING

I have yet to see an autobox that is not checked that way, the "COOL" dipstick mark is for filling a gearbox to an appropriate level if for some reason the engine cannot be run at the time (as in service/repair routines).

The engine & gearbox should be at operational temp when using the "HOT" mark to check the fluid level.

strongsail

absolutely, you check the level with the engine idling. When the engine is off, all the trans fluid collects in the pan and you get a high reading on the dipstick. With the engine running, the fluid is pulled into the torque converter and all the passages and the level in the sump will be much lower.

If you fill an empty trans to the full mark with the engine off, it will be way low with the engine running and the trans will not operate normally and will overheat, remember the fluid cools the trans as well as makes the car move.

VQT