When I slow down to stop or go slow (under 1100 in overdrive there is a clunk as the auto box changes down). Is this the sign of an expensive repair or can I do something to fix this before it dose more harm? There is also a lag and a clunking engagement of drive when the car is cold and you come out of park or neutral into drive. It only happens first off. Any help would be appreciated as I am new to the forum and to working on Magna's, especially the V6. Thanks for your input. Cheers John

Go and have your transmission serviced. Get the mechanic to adjust the bands, change the fluid and replace the filters. DON'T tell them you think there's something really wrong with the transmission otherwise you leave yourself wide open to be taken for a ride by the more unscrupulous repairers (they are out there...not all, just some). If, after a full service, you still hear the clunks and stuff that's when you get the mechanics to search further. I'm no expert but it sounds like the tranny is low on fluid or the vacuum modulator is a bit wonky.
Read the excellent info on this page: http://www.familycar.com/transmission.htm

stroppy, have you actually owned a 2nd gen with these symptoms?

OP, read up and adjust the throttle position sensor (TPS). I bought a 2nd gen with these symptoms and a TPS adjustment fixed it. Mind you, the 2nd gen auto does jerk into gear when cold due to the higher idle, so foot on the brake. lol

Thanks for responding guys, I did an auto fluid change with filter kit and Nulon fluid 20,000 klms ago and it did not change the problem then. My daughter has used the car for the last year since I did the oil fluid change and now I have the car back again and want to fix the problem with the clunk down from overdrive. There does not seem to be any slip at all. Ok MadMax, where do I read up on the TPS and how to adjust it and also how to locate and adjust the vacuum modulator if the TPS does not fix the problem? I read the good article on family car Stroppy, thanks for the info. Cheers John

Thanks for responding guys, I did an auto fluid change with filter kit and Nulon fluid 20,000 klms ago and it did not change the problem then. My daughter has used the car for the last year since I did the oil fluid change and now I have the car back again and want to fix the problem with the clunk down from overdrive. There does not seem to be any slip at all. Ok MadMax, where do I read up on the TPS and how to adjust it and also how to locate and adjust the vacuum modulator if the TPS does not fix the problem? I read the good article on family car Stroppy, thanks for the info. Cheers John

You're welcome...of course. MadMax probably knows more about Magnas than I do so his advice is invaluable. I'm working on previous experience with a couple of Holdens which showed the symptoms you wrote about. In one case, a thirty cent piece of vacuum tubing fixed the crazy change pattern and clunking on a Commodore4 (shitbox, that car!) I owned. At the time I thought I'd be up for a new Trimatic tranny but it turned out that a hose to the vacuum modulater had perished because some twit had dropped some type of oil on it during a previous service. I was fortunate in that the head of the service department at Geoff Brady Motors worked out what the problem was in a snap, then he smiled and said..."See, I just saved you be taken by some other tranny mechanic for hundreds of bucks!" The second car I had that started doing weird clunking in the tranny was a VL Commodore and that turned out to be a faulty modulator.

Good luck with it all...hope it all turns out well for you.

Mad Max, can you give the guff on how to adjust the TPS? Thanks, John

Its in the manual. You will need to get your hands on a multimeter.

http://www.lisho.net/?page_id=3

Johng12: I used to have this problem happen in my old KS verada.. so while I was driving around town I used to turn the overdrive off as I was slowing down under 60km/h to avoid the clunk, but it also doesn't hurt to leave the O/D off around town anyway.