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Chris (aka- Moose)
Chris (aka- Moose), Technician
Category: Transmissions
Satisfied Customers: 1764
Experience:  16 yrs. experience with auto, manual, & CVT drivelines
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Sienna: I have a Toyota Sienna - 2010, Canadian, 106,000km

Customer Question

I have a Toyota Sienna - 2010, Canadian, 106,000km (65000 miles)
Never had any issues, there are NO check engine lights.
After a long road trip (~14hrs over 2 days) the van started having sluggish acceleration. It feels like the van is trying to get going in 3rd gear. I can manually shift from L/2/3 to help a bit, but it will still occasionally seem to disconnect from the gears -- it is about to shift from 2nd to 3rd for instance, and the engine will suddenly rev from 2500rpm up towards 3500/4000 before shifting.
It seems to be temperature related -- if the car is cold it will run fine, but once hot this starts to happen. I'm not 100% sure of this, as it has only been 3 days that we've seen this.
I suspect we need to take it in to Toyota, but I'm hoping it is something simple vs major.
Submitted: 2 years ago.
Category: Transmissions
Expert:  Trans_ Service replied 2 years ago.
Hello. Welcome to Just Answer. Please allow me to assist you.
This sounds like the transmission has some seals that are not sealing properly, solenoid valve are not sealing properly, or there is a lot of contamination of the fluid.
If this vehicle was in my shop, I would be recommending to you to get the transmission completely flushed, using a machine specially designed for this. This procedure allows all of the old, dirty and/or contaminated fluid to be removed from the system (where a 'drain and refill' leaves 3-4 quarts of the ATF still inside the transmission (torque converter, cooler, cooler lines, etc)...Additionally, I would also recommend that a transmission fluid conditioner be added. This will soften the hardness of the internal seals. 90% of the time, when we see a slipping condition like this, the trans flush/conditioner additive usually cures the problem. In our shop, we would charger 189.95 + tax for thsi service.
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