hesitation into 4th gear AT

[samus11]

I've got an 08 Yaris Liftback-automatic trans with ~20,000 miles on it. Love the car, and have had no issues so to speak of.

One concern I have has to do with it sometimes taking a while to shift out of 3rd to 4th. Occasionally it will not shift until almost 60mph (compared to it's usual shifting around 40-45). At this speed, the noise is considerably louder the shift feels rougher.

I don't have a scanguage or a tach to provide any more info. Any reason it would be doing this? Any remedies?

[david_827]

is it having this issue when the "COOl" light is on on the dashboard???? This sometimes happens to me when i try to push my car before it warms up.

[CTScott]

The Yaris prohibits 4th gear until the AT fluid and engine coolant reach a threshold (which is typically when the green "cool" light goes out, as the coolant takes longer to heat up than the AT fluid does).

If you are interested in being able to override that behavior, I figured out how to do so using just a switch and a resistor:

http://www.yarisworld.com/forums/showthread.php?t=37691

[samus11]

It does happen mostly at the beginning of drives, but I feel like I've experienced it after the green "cool" light has gone off.

Maybe I'm just going crazy.

[Golddeenoh]

the green light goes out at 130 degrees Fahrenheit normal operating temperature is between 184 and 194 degrees Fahrenheit. the oils will warm up before the coolant get that hot, the question is are you getting everything hot enough, long enough to operate properly? how long do you typically drive in one outing? if you drive less than about 10 miles in one direction then the engine and trans operating temperature has not been reached and the system safety precautions will not allow the trans to sift into higher gear. this is done to prevent strain on the engine which can cause premature ware and failure.

[MadMax]

Yep, even with the 'cool' light off I still find it takes a while for the transmission to warm up sufficiently to shift into OD (4th).

Unless this is happening after you've driving for a while (5-10 minutes) then it is completely normal.

By the way, where are you in the great state of Texas?

Cheers! M2