transmission fluid change

I am in the proccess of changing my gf's transmission fluid in her 99 sienna and the book said it has differential fluid. so i drain the regular trans fluid about 3.5 qts came out which is what the owners manual said to refill. then i drained the diff fluid and 2 qts came out the book said only .8 qts. So I'm guessing since I cant find a fill hole for the diff fluid, the are the same and i just drained some of the new trans fluid out of the diff hole. I need some sleep. And it's hard as hell to get an accurate reading on the dipstick.

I'm pretty sure the diff and trans fluis are separated. (from 98 thru 2001 I think) When I drained mine, the diff fluid was much cleaner than the trans fluid.

The diff fluid does not have a dip stick. It has a separate drain plug on the back of the diff. Is this where you got 2 quarts from? Above the diff drain plug there are 2 bolts. I removed both, and filled from there till it comes out. I did drain and fill about 0.8 Q. in the diff.

When I refilled my trans, I thought I put in the recommended 3.8 Q and the level turned out right. I too had difficulty getting a good reading. Seems the design splashes oil on the dip stick making it hard to read. I dont remember how I was able to get a good reading, but it did take some patientce and multiple tries.

Good Luck.
Dan Strong


I am in the proccess of changing my gf's transmission fluid in her 99 sienna and the book said it has differential fluid. so i drain the regular trans fluid about 3.5 qts came out which is what the owners manual said to refill. then i drained the diff fluid and 2 qts came out the book said only .8 qts. So I'm guessing since I cant find a fill hole for the diff fluid, the are the same and i just drained some of the new trans fluid out of the diff hole. I need some sleep. And it's hard as hell to get an accurate reading on the dipstick.