300Tdi Auto Question.

[Matbrown]

Just a quick Q about autos, i'm new to them so not sure if i have a problem or it's my driving!
When just driving on roads at normal speeds the revs sometimes jump up suddenly then settle as if the clutch was slipping when changing gear or is it just my pedal control?



Mat.

[beast5680]

the engine will sound slightly like its slipping the clutch as effectively its doing just that as it builds speed to change up to the next gear, if you hold it at a constant rpm and drive a flat road you,ll hear it .
if your not used to it it does sound odd when they change gear

[rommelsraider973]

Is it all the time? Could be a loose connection on your alternator? Just a thought mate!!

[Matbrown]

Not all the time, just done it a few times.
It's not the standard gearchange slipping noise, when it goes to change up a gear the revs will increase briefly.



Mat.

[Matbrown]

What is there on an auto instead of a clutch?



Mat.

[bezzabsa]

viscous coupling....in other words - try stirring cold treacle - them try again with hot treacle...lol

[Matbrown]

Could this be developing a fault, does it share the same fluid as the gearbox?
As although it doesn't effect the driving much it's very annoying!



Mat.

[Xtremeteam]

viscous coupling....in other words - try stirring cold treacle - them try again with hot treacle...lol

not quite but ill explain in a bit.

the engine drives one side of the torque converter,this then spins with the fluid inside,on the inside of the TC is vanes which spin the fluid like a pump,as it moves its goes against the otherside of the THC which also hase vanes but pointing the otherway,thus giving it resistance,as it spins the fluid moves faster & gives more resistance,in the middle of the TC is the stator which then turns the fluid back in the oposite direction & starting the process all over again

[Matbrown]

So would a fluid change help?



Mat.