Hey guys,

Got a bit of an issue with the auto in my EF Fairmont i6, been like this, well ever since i bought the car i guess but never knew it had a problem till it happend to me a few weeks later.. So here goes..

The problem seems to be the way it shifts down to first gear from second gear (and third depending on the speed im doing), when slowing down to a slow speed then accelerating again. What happens is i'll slow down and the car will be rolling and when i accelerate again it will change from second gear back to first, but its like it slips, it revs out for a split second then will kick into first gear pretty harsh depending on how much pressure is applied to the accelerator. Sometimes when i slow down to take a corner pretty slow then hit it, the car just revs out, then kicks into first so harsh it chirps . Sorta like dumping the clutch kinda feel if that makes sense?

Lately ive really been paying attention to it and it seems it does it even slowing down to a stop. You can feel the car kinda jerk forward as it goes from second back to first. Other than that the auto shifts up and down smoothly, just downshifting to first is my main concern.

The auto has recently been flushed with the filter changed in hope of it fixing the problem but its still there, even got a guy from the gearbox place who serviced the auto to testdrive the car while i sat in the passenger seat, and luckily enough it happened when he drove it, he hit the gas coming out of a corner and it reved out, kicked back hard into first gear with a chirp. Straight away he said it was changing straight from third gear to first without even selecting second and that the TPS was causing the problem. So i thought okay maybe he could be onto something, but i changed the TPS and it still has the same issue. The same day i decided to test the auto a bit to see if it does it all the time, by manually selecting second and driving at say 30kmh then flooring it.. Found out that it does it not only from third gear as the guy said but second gear aswell depending on the speed and how much pressure i apply to the accelerator.

So now im thinking it may be a solinoid or whatever controlling the down shift to first or something inside the box.

Hopefully i wont be needing a full rebuild, lol just havent got the money for that right now.

Anyone here had a similar problem? If so how did you go about getting it fixed?

Any help will be greatly appreciated. Thanks in advance.

Probably needs a rebuild, how many kms? First thing to try is to clean all the terminal plugs that go the the gearbox. There is a little white module attached to the gearbox. Get underneath the car, I'd pull all plugs, clean them and put them back in.

I not 100% sure but each gear has a little clutch and they can wear out so from 1 to 2 might be slipping but 2 to 3 and 3 to 4 could be fine. I would get it down to a trans place see what they think, hopefully its not to exspensive.

Thanks for the replys..

The gearbox has done almost 220,000ks now.

Will try cleaning out the connectors and terminals that go to the gearbox and see if anything changes. The auto will definately be getting a full rebuild in the future when i take the car off the road, but for now i just want it to shift as per normal, just incase it might be puttng a bit of un-needed stress on the uni's and diff etc with the harsh downshifting.

I've got a few weeks off at the moment so will definately go back to the trans place and get someone else to drive the car and get them to diagnose the problem. Will let ya know how i go and hopefully get the problem fixed.

Thanks again.

Check your fluid levels and condition of the fluid. If you don't drive it too hard you might get away with a fluid change until you want to rebuild. As was said also check the solenoids but if it is only when downchanging I wouldn't think a solenoid problem.

Interestingly I had the exact same problem, to the letter in my EF Fairmont.

The transmission in my car has never been anything to write home about. It started having that problem a week or so after I got it.

I had a mechanic tell me it was a bush that was loose at the back, and it was leaking fluid. So that got changed, topped up the fluid and away she goes.

However during the time it was slipping, I must have damaged the drive plate. A few months later it developed a rattle from the bellhousing which caused me a lot of bafflement. I had one mechanic tell me it was tappers, another tell me it was the catalytic converter, until I finally hopped under the car and heard it loud and clear.

It should be something that you should pay attention to quickly, because what happened to mine is, the damage to the drive plate caused un planned for pressures on the crankshaft and gearbox. My auto is now basically unusable, and my bottom end will need a rebuild soon.

It sounds like your coast clutch or engine braking clutch has worn out - called the C4 clutch.In a BTR transmission there is 4 clutch packs,2 bands & 2 one-way sprag clutches.

When you drive along with your foot off the accelerator coasting,does it free roll as if you have put it in neutral?

Doesnt really free roll when im coasting, i mean ill take my foot off the gas and it'll roll for a seconds till the revs drop down then the speed decreases, but thats normal. But you could be onto something with what you have said about the clutch packs so i'll see what the trans place have to say about it. Thanks for all the advice guys!!