Automatic Gearbox- Unwanted Shifts - Glaikit Wee Scunner {P}
Been driving a Toyota Avalon rental car for the past two weeks. Very comfortable cruiser in California/Arizona/Nevada. It had a 3.5l engine, 268 bhp (SAE) and a 5 speed auto box with a (partial) manual over- ride.
I noticed that when I hit a decent up hill stretch of freeway at 75mph on cruise control, it would drop down two gears. This caused noticeable torque steer to the right - which must be downright dangerous in slippery conditions and was pretty alarming at times.
This happened even after selecting 'top gear' in manual mode.
Most UK spec manual cars could maintain this speed in top gear so is the Toyota auto set up peculiar?


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I wasna fu but just had plenty.
Automatic Gearbox- Unwanted Shifts - Glaikit Wee Scunner {P}
Bump. Does no one on the forum drive an automatic?
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I wasna fu but just had plenty.
Automatic Gearbox- Unwanted Shifts - Muggy
I do, but I cannot offer any suggestions unfortunately; I have never had any problems like that.

Mine is a 1996 Suzuki Swift.
Automatic Gearbox- Unwanted Shifts - expat
I have a 4lt Ford Falcon auto 2003 model. It doesn't drop gears like that. I just put it into drive and it goes. Never touch the tiptronic side of things. The only reason it would drop gears on a hill would be if it needed lower gears to keep up the speed. Mine certainly doesn't do anything like that. It has heaps of torque and just lopes along quietly and easily. Mind you we have very few steep hills where I am. I would think that perhaps it had a fault with the transmission.
Automatic Gearbox- Unwanted Shifts - jc2
Ford C3 used to do it but that was because it had vacuum k/down rather than mechanical.
Automatic Gearbox- Unwanted Shifts - Kevin
What altitude were you at?

Kevin...
Automatic Gearbox- Unwanted Shifts - Micky
Sports mode? Does the speed remain the same under cruise control? Or does it accelerate? If the latter then perhaps a problem with cruise control. Take it back and demand a 4.6 Mustang with stick shifter. You know you want to really. Enough of this auto nonsense.
Automatic Gearbox- Unwanted Shifts - Stargazer {P}
All the Holden Commodores (3.8l auto) and Toyota Camry autos I drove as part of work in oz were similar to Expats post, no problems with downshifting in cruise unless attempting to use cruise to go up a steepish hill....quite a big 'jump' just as the car crested the hill and no longer required the lower gear.

Working at the top of a very windy mountain road made using cruise too much quite interesting!
I did manage the whole 2 mile ascent once letting cruise do its own thing but that was in a 5.0l V8 Ford Falcon Ute.

Happy memories

StarGazer
Automatic Gearbox- Unwanted Shifts - Kevin
Forget the altitude question.

Look here:

www.lemonlawclaims.com/toyota_avalon_transmission_...m


Kevin...
Automatic Gearbox- Unwanted Shifts - Glaikit Wee Scunner {P}
Thanks Kevin,
Looks like I am not the only one to suffer.
Otherwise a very relaxing car to drive.
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I wasna fu but just had plenty.
Automatic Gearbox- Unwanted Shifts - Bagpuss
From Kevin's link, cut and pasted in its original shouty form:

"OTHER TIMES, I WILL PRESS THE GAS PEDAL AND HAVE NO RESPONSE FOR SEVERAL SECONDS BEFORE THE CAR TAKES OFF. IT MAKES IT VERY DIFFICULT TO MERGE INTO TRAFFIC AS I NEVER KNOW WHEN THE CAR WILL GO OR NOT GO."

Sounds to me like Toyota is trying to give the Avalon the driving characteristics of a Turbodiesel;-)
Automatic Gearbox- Unwanted Shifts - Muggy
Ah - hang on a minute - "no response for several seconds"....

The ATF has got "cooked"; in these instances it *should* return to normal response after a few minutes of gentle driving, but I think I heard somewhere that if the ATF is frequently getting "cooked" it will need changing as it will degrade as a result?
Automatic Gearbox- Unwanted Shifts - David Horn
It's a cruise control thing, if the Accord I drove last week shares any gearbox traits. As you approach the hill, the car starts to slow, so the computer pulls the throttle cable in. However, the hill gets slightly steeper, but the throttle isn't depressed enough yet to keep the speed up. So the computer continues to reel in the cable but the time lag causes it to hit the stop and the kickdown point before it starts to accelerate appreciably.

Hitting kickdown on the motorway usually causes any autobox to drop to 2nd gear (maximum power at about 5000RPM), explaining the abrupt jolt. I suppose it could be a fault with the kickdown sensor though, or the whole system could be badly designed. The Accord never had enough power to induce a torque steering effect. (*David runs out to hug his turbo diesel*).