1997 autogearbox problems...
Posted: Mon Aug 24, 2009 8:49 pm
I have an A8 (not S8) 4.2 automatic which have developed a couple of gearbox problems.
This is how the problems developed:
A year ago the headgasket in the engine was changed because it had overheated in slow traffic in southern france. The audi specialist mechanic took the car for a (very extended) 600miles testdrive/checking the engine was okay and didn't overheat.
A. When I got the car back I went straigth on holiday with it and the engine was fine but the gearbox clonked very hard when downchanging for mild overtaking acceleration on the motorway from 5th to 4th gear. So I used tiptronic to avoid it changing down.
B. Then when driving on the motorway the revs fall down when coming of the accelerator. The revs fall about 500 rpm at 80 MPH and then really clonks back into lock so the car sort of bangs back into 5th gear when the revs have fallen a sufficient amount. So I try to help and anticipate the clonking point and accelerate a bit so as not to have the car lurch.
C. Then this summer the car started develop a sort of metallic screeching sound when accelerating slowly from 0- 25 mph. I think this is related to the gearbox as well.
The only possitive regarding the gearbox is that I can lock it in tiptronic which stops it kicking down when accelerating from 65 mph and also when accelerating up through the gears if changes smoothly and also changes smoothly down when slowing for traffic.
Just adding that I've been reading a lot up on this on the internet and it seems most cure the problem by having a complete service i.e. oil, filter and gaskets. Some say it's the torque converter not locking tight and that the torque converter needs changing, while another still say it's the solenoids which are clogged.
It has had two oil changes during it's life, one at around 80.000miles and one around 110.000 miles, it's now done 120.000 miles.
I am pretty confused but as I've highlighted the problems and how they developed perhaps you guys can help me?? Would be fantastic as I don't want to shell out for a complete rebuild if it actually isn't needed.
This is how the problems developed:
A year ago the headgasket in the engine was changed because it had overheated in slow traffic in southern france. The audi specialist mechanic took the car for a (very extended) 600miles testdrive/checking the engine was okay and didn't overheat.
A. When I got the car back I went straigth on holiday with it and the engine was fine but the gearbox clonked very hard when downchanging for mild overtaking acceleration on the motorway from 5th to 4th gear. So I used tiptronic to avoid it changing down.
B. Then when driving on the motorway the revs fall down when coming of the accelerator. The revs fall about 500 rpm at 80 MPH and then really clonks back into lock so the car sort of bangs back into 5th gear when the revs have fallen a sufficient amount. So I try to help and anticipate the clonking point and accelerate a bit so as not to have the car lurch.
C. Then this summer the car started develop a sort of metallic screeching sound when accelerating slowly from 0- 25 mph. I think this is related to the gearbox as well.
The only possitive regarding the gearbox is that I can lock it in tiptronic which stops it kicking down when accelerating from 65 mph and also when accelerating up through the gears if changes smoothly and also changes smoothly down when slowing for traffic.
Just adding that I've been reading a lot up on this on the internet and it seems most cure the problem by having a complete service i.e. oil, filter and gaskets. Some say it's the torque converter not locking tight and that the torque converter needs changing, while another still say it's the solenoids which are clogged.
It has had two oil changes during it's life, one at around 80.000miles and one around 110.000 miles, it's now done 120.000 miles.
I am pretty confused but as I've highlighted the problems and how they developed perhaps you guys can help me?? Would be fantastic as I don't want to shell out for a complete rebuild if it actually isn't needed.