I had my friend's 06 Prius at the dealer for a transmission service and an axle seal repair. The tech allowed me to observe the transmission service portion of the job.
The transmission fluid was the factory fill Toyota WS-ATF and had almost 85k on it. The car spent the first 60k of it's life in blazing-hot Phoenix and the last 25k in hilly Santa Cruz, CA.
The old fluid smelled fine, and still had a slight red tint to it. There's no dipstick on this car, but you can tell while it was draining that the fluid was dark but still slightly red, not completely burnt.
Almost 4 qt of WS was pumped back in after the axle seal was replaced. A drain and refill on a Prius removes ALL of the fluid, since there is not a torque converter. Some of the whine that you hear during acceleration has disappeared. Although it is possible that the whine was caused by a low fluid level, I think that is unlikely since the axle seal leak has only appeared in the last 5k and it is a moderate seep as opposed to a dripping leak.
So if you have a Prius and the car seems to whine a bit than it did compared to new, then consider changing the transmission fluid. It only takes 4 qt of fluid ($40) and a fluid pump of some kind.
The transmission fluid was the factory fill Toyota WS-ATF and had almost 85k on it. The car spent the first 60k of it's life in blazing-hot Phoenix and the last 25k in hilly Santa Cruz, CA.
The old fluid smelled fine, and still had a slight red tint to it. There's no dipstick on this car, but you can tell while it was draining that the fluid was dark but still slightly red, not completely burnt.
Almost 4 qt of WS was pumped back in after the axle seal was replaced. A drain and refill on a Prius removes ALL of the fluid, since there is not a torque converter. Some of the whine that you hear during acceleration has disappeared. Although it is possible that the whine was caused by a low fluid level, I think that is unlikely since the axle seal leak has only appeared in the last 5k and it is a moderate seep as opposed to a dripping leak.
So if you have a Prius and the car seems to whine a bit than it did compared to new, then consider changing the transmission fluid. It only takes 4 qt of fluid ($40) and a fluid pump of some kind.
