strange behavior of V70 automatic 125 kW

Morning.

What could it be?

Last week I was cruising the highway at 180 km/h (110 mph) and want to
pass an other car. So I made a kickdown. But the engine has roared but
no acceleration took place. The car was going slower and slower. So I
went to the emergency lane. At appr. 80 km/h (50 mph) the car came back
to respond to the gas pedal. But only up to appr. 90 km/h (55 mph). Then
the engine roars but no acceleration took place again. So I made a stop
on the next lay-by. I've switched the engine off and did wait a minute.
Then I've launched the engine again. And all was working fine. Since
this has happened I've made more than 2'000 km (1250 miles) without any
inconveniences.

But the uneasy feeling remains that probably the car wculdn't accelerate
when I do really need it.

Has one of you an idea what the reason for the missing acceleration
could be?

TIA and kind regards, Friedrich

 

Well around here you certainly wouldn't hear of one casually cruising
the highway at 110 mph! That must be hard on the fuel economy.

From what you say, it sounds like the problem is in the transmission,
since you mention the engine revs up. First things first, have you
checked the fluid level? Does it look a nice clean red color or is it
burned? You may have a worn out clutch pack in the transmission. Auto
boxes do typically start to slip under load when they wear out.

 

You are destroying the trans, its obviously overheated and the torque
converter slipped. If you dont want to burn out the trans you need to
keep the temp near 175f, for ever 25f over you shorten fluid life by
20000 miles. If that was my car I would change the oil now to
synthetic, put in a trans oil temp gauge , then you will know how big
a transmission oil cooler you need by seeing how high the temp goes.
An engine oil temp gauge should also be installed, now you have a
coolant gauge, now oil temp. High temp is what ruins auto
transmissions, and their oil, I bet you oil is brownish and burnt
smelling, so its junk from the excessivly high speed you drive, and
flooring it at 110mph is plain old dumb. I would regret buying your
car used. You dont own a race car.

 

Thank you for your clear and impressive explanation. You are right, my
oil is brown and old, and my Volvo is no race car. I'll exchange the oil
next week.

Under normal circumstances I never drive my car with more than 75 mph.
But when I have to go more than 500 miles, then you'll love the German
Autobahn and push the kickdown.

Thanks again, and kind regards, Friedrich

 

Unfortunately it's probably too late if the fluid is already brown. It
should be perfectly fine to reach those speeds for short periods of
time, but to cruise like that has got to be hard on things.