I've got a new problem with my '98 V70 XC wagon that I hope someone can help me diagnose. The last 2 times I've driven in the mountains, while pressing the accelerator to pass someone on a hill at 50-50mph, instead of the car shifting down to a lower gear to accelerate, I experience a very disturbing thumping that feels like it's coming right through the floorboard. If I ease off, the bucking sensation stops, but I'm then slowing down. Eventually it seems to find whatever it needs and does kick down and I take off, but clearly something is not functioning correctly. The car only has about 82K miles and otherwise drives fine. It's only when I'm trying to pass while going uphill at a moderately high speed that I experience the thumping. If anyone has an idea of what this might be, I would be most appreciative. Otherwise, it's in to the Volvo dealer, and who knows what they're going to tell me. Thanks.

 

Cars' do not "kick in" to go into overdrive.
If you press the pedal it will go OUT of overdrive and into a lower gear (kickdown)
With that being said.....want to try your question again and say what you mean?

 

Obviously I'm not a car guy, so I apologize for the poor description. It's simply that when I step on the gas to pass somebody at 50mph on an uphill grade, instead of feeling the car downshift and accelerate, I feel it start to buck and there's a thumping through the floor. If I ease up, it stops, but I lose speed because I'm on a hill, trying to pass. To use your term, I was expecting it to kickdown to a lower gear so I could pass with power, but instead got thumping and loss of power. I hope that's clearer. Thanks if you have any ideas what it might be.

 

Probably a shot torque converter in the tranny
(You probably need a transmission)

 

Check your transmission fluid level/ condition.
Dipstick is yellow and hidden near right side of radiator under some things.
It's in that general vicinity; just look for yellow.
See what it looks like hot.
Although this DOES NOT sound good, check your fluid first.

 

And about taking it to a dealer- don't waste your time unless you have money to burn, and or enjoy being financially and ethically violated.

 

Thanks for the responses. Does a shot torque converter require a whole new transmission, or can it be replaced without replacing the entire transmission. If not, what is a reasonable estimate as to what a new transmission would cost?

Hard to believe that a car that only gets drive 6-7K miles a year should have blown a transmission, but this car continues to surprise me with all the things that have gone wrong.

Thanks again.