slipping?

Its called a continuously variable transmission, and that's what its supposed to do. There's a lot of good information around here for newbies that explains the system in detail.

 

I can assure you that there are no 'gears' that might engage or disengage, and no clutch that disengages under human or computer control. (there is a clutch that would slip if either the engine or transmission were to lock-up at highway speeds, lets hope that never happens)

OTOH, only the steering is under your control, all the other controls and pedals are suggestions to computers. So what you wanted to do and what happens may differ.

One interesting 'feature' of the eCVT (also called HSD and PSD) is that engine RPMs are almost completely unrelated to the vehicles speed. (they vary by the power needed to propel the car as you requested)
Toyota Prius - Power Split Device

 

Another thing is that if you start driving before the engine is completely up to temperature the computer will use more electric motor power on acceleration and less gas engine. Once the engine is up to temperature you can feel the shift to more engine power. Once again, completely normal.

 

Welcome to PriusChat. Here is a post that has more information about the eCVT.

3rd Gen Hybrid eCVT Transaxle in the Classroom | PriusChat

 

My 2008 Prius has 88,000 miles. Transmission serviced 1,000 miles ago. Noticed now tranny seems to slip considerably when accelerating, and notice engine rev increases during this time. Avg MPG for tank has dropped to 38 vs 42 before slip began occuring. Engine is warm, rolling on power slowly but still has slip, eventually "catches up" but this performance issue is relatively new, within last 1,000 miles. You're saying this is normal? I'm listening, but it doesn't seem right.

 

Wrong forum, first time poster. Are you for real?

 

Anyone out there have any thoughts on this issue?

 

Yes, not sure what you mean by wrong forum. Yes, I'm for real and so is the problem with vehicle.

 

There is absolutely nothing to slip in this transaxle. The gears are always engaged, never shift, no neutral, no reverse.
ATF changes get the crud out and provide fresh clean lube for the gears and bearings, there are no clutches to wear.

Fuel mileage varies seasonally. Are you using more AC this time of year?
You can use fuelly.com to watch your FE and see the seasons change.

The idea is to keep the RPM and throttle opening at the best fuel useage for the power requested by the go pedal.

Enjoy the future now in your modern, high-tech, fuel efficient car !!!

BTW, The brakes are a real connection and will work when there is no power anywhere in the car.

 

Bill, thanks for the reply. Not using A/C any more than usual, which is fairly constant for me, much to the chagrin of my wife. It may not "slip" as you say, but there is definately something different about how this car is performing. It seemed to begin in July when I was driving with a fully loaded (5 people) vehicle. Took much longer to get to freeway speeds, I'm okay with that since it's about as powerful as my wife's sewing machine, but it's this feeling of clutch slip that has me concerned. Even now, with just the driver on board, it doesn't get to speed as quickly as it did when purchased early this year. When I casually addressed this issue with a guy at the transmission shop, he started talking about replacing the tranny to the tune of $6K. So, you can understand my concern about the vehicle's performance. I read about the battery issue affecting MPG, but haven't encountered what this slippage issue may be. I understand it doesn't "slip", but that's the best explanation I have for the sensation and what I hear when it occurs. Ideas?

 

Oh, I see now, wrong Gen area. Just put in search for tranny slipping and I ended up in Gen III space. Mr "Friendly", no need to be rude, perhaps a different moniker would be more appropriate.

 

You may be exceeding the weight requirement with 5 adults. If all average 200 Lbs each that 1,000 LBS, limit is 850 LBS

 

Well actually there is this safety clutch on the flywheel area outside the transaxle's lube, I think it is.
The videos talk about it.
There is a possibility that it has gone south. But if this what is happening you would smell that gadawful burning brakes or clutch smell. I have never read about this component going bad. Plus it wouldn't do it for long before it burned out completely.

Good luck, keep us posted.

 

Just checking. Too many brand new posters post some nonsense and never come back.

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Good job on introducing yourself as a jerk BTW.

 

Boys , Boys,,,, go to time out.

 

Thanks for the thought, 4 adults and small child, wouldn't have been anywhere near 850 lbs. That's good info to know, though.

 

Bill, another good thought, however there is no smell occurring.

 

Okay, Mr. Friendly, perhaps I misunderstood what you were initially attempting to convey, however, the "jerk" comment only proves what I initially thought was correct. If I shared all the symptoms I was experiencing with the slipping issue, what part of that query made you suspect it was nonsense, especially since it was in an area dealing with slippage. Geez, dude, really? Again, a different moniker would be appropriate. Don't bother to respond since you can't seem to address the actual topic and question.

d

 

Was the battery disconnected when the transmission fluid was changed? It could be that it is still relearning your driving and the excessive revving is a side effect.