AU automatic troubles

macman · 17-03-2012, 05:10 PM

The auto in my 5.0l AU2 has developed an issue where if you downshift into 2nd or 1st (to slow down) it just goes into neutral. D to 3rd is fine, gearbox upshifts by itself fine, doesn't slip.

Firstly, doesn't seem to matter at what speed - into 2nd at 30km/h, into 2nd at 60km/h, still hits neutral until you touch the throttle...

Things I've tried:

I've just reset the ECU etc by leaving the battery disconnected for two days, no change (except for the engine having to re-learn idle speed).

Changed the auto fluid (Castrol TQ95) and fitted a new pickup filter. Drained around 4.5 litres by just dropping the pan, then refilled it ~4.0 litres (till full), started up and ran through the gears and needed to add another ~500ml (till full).

Last of all, at the same time I fitted a PWR trans cooler. Cooler gets nice and warm (indicating fluid flow) but still no 1st or 2nd when downshifting manually...

Any ideas?

BHDOGS · 17-03-2012, 05:25 PM

Neutral selector switch

J.C. · 17-03-2012, 05:51 PM

^^^^^ What he said, plus did you change the trans filter and if so, do you have the old one?
Check it out as it tells a story if there is a mechanical failure happening. If a clutch is failing for example, the material can vary in size from very fine particles that you can feel with your fingers, to chunks.
Was there any crap on the trans pan sump when you removed it?

Been down this road. It can be a scarey one. One I don't wish on any T owner due to the differences with the T trans.

macman · 17-03-2012, 06:47 PM

The trans fluid was BLACK. Looked like it had never been changed (I've never changed it since I've owned it). The pan gasket had been leaking by the looks too.

In the pan, the magnet was reasonably thick with very very fine metallic particles.

Going to remove the neutral safety switch, give it a clean and see what happens.

The fault appeared after my rad cap failed about three weeks ago. Came outside to the car in a pool of coolant - wonder if it has upset the switch?

J.C. · 17-03-2012, 06:53 PM

There is no harm in doing what you intend on doing. Can't hurt. Do the simple things first.
Can you recall if the fluid "smelt" burnt at all?
I'm interested to see what the remedy and outcome is.
Reckon you can keep us posted on that?

5.0 ED · 17-03-2012, 07:00 PM

If your gear selector is correct and you manually select 2nd and then manually select first, and it doesn't engine break, but the car will still engage when you put your foot on the pedal, then you will have a faulty clutch pack, the car is now running off the sprag "one way clutch" and normally drives on this in D, but because you are manually use the shifter slides the shift rod further and opens an extra oil passage which turns on the clutch pack on top of that to engage engine breaking.

Not an electronic fault, but a mechanical, gearbox overhall to fix it fault.

If this is a T series and your using the buttons on the steering wheel to change down gears, then try using the manual shifter instead. And if the manual shifter does work, they you may get away with cleaning the valve body.

macman · 17-03-2012, 07:43 PM

Okie dokie. Cleaned the two connectors that go to the inhibitor switch. One had some corrosion on one of the terminals. It's made no difference.

Yes, it is a T-Series (my TE50) and it behaves exactly the same in ESS or normal automatic shift mode.

J.C. the fluid didn't strike me as smelling burnt, no. It was very very dark though (darker than the fluid I drained from my TS50). The amount of material on the magnet did make me think though, but than again it's done at least 50,000k's since I've owned it and I've not done a fluid change previously (and doubt the previous owner did either) so I justified the build up of material that way. Are the clutch materials magnetic?

5.0 ED · 17-03-2012, 10:56 PM

Well just a note i will add in here, that i have seen a few BTR's do it, and most of them have continued to live on for a fair while longer, just with no engine breaking, my parents had a v8 fairlane that was like it for years. But it was also drivin nicely.

macman · 18-03-2012, 02:31 PM

So my next three questions:

1. Were the fine metallic particles on the magnet the clutch materials?

2. Is this because they just wear out around these k's or have I done something to cause this? Is it caused by a slipping box, overheating etc etc?

3. Are these ebay rebuild kits (consisting of clutches, bands, bushes, gaskets, seals/rubbers) going to fix my issue and has anyone any experience in these kits?

P.S. Thank you for the help so far.

skip02 · 18-03-2012, 05:20 PM

only costs $40 for a new inhibitor switch i would try that first if the connections were corroded good chance inside the switch is aswell.I have seen them rusted solid to the shaft and had to destroy the switch to remove it .That part of the car consistently cops a lot of water

Mr Hardware · 18-03-2012, 07:11 PM

Mine has the same thing, and it has been like this for the last 130,000klms.

I'm pretty sure 5.0 ED is right, last time i asked about it someone said "something something sprag clutch something don't worry about it".

macman · 18-03-2012, 10:01 PM

Thanks skip02 - I'm going to snatch the inhibitor switch of my TS50 and try it in my TE50 and see what that tells me. I've had the TE50 up and down off the stands that many times over the last two weeks it can't hurt to do it again!

Mr Hardware - interesting to hear from another AU owner who has the same issue (and that you can still "live with it" like "5.0 ED" also said). If it wasn't a T-series with ESS I might leave it however it then defeats the purpose of the function (IMO). I'm probably obsessive as well because when things don't work, it really gets to me!

I often flick back into 2nd gear in traffic or to avoid gaining speed down-hill so will definitely need to get it sorted I think...

I'll swap the inhibitor switch this week and report back. Failing that, I'll take it to a trans specialist and look into a rebuild :(

5.0 ED · 18-03-2012, 10:17 PM

I can 100% tell you that it is not anything at all to do with the inhibitor switch.

The transmission has electronic control as well as mechanical, the electronics are limited in what they can/cant control, and this is something they cant control.

The electronics can only control what actual gear it is in, not its engine breaking, it also controls shift firmness, and the lock up touque converter, but not engine breaking.

Yes you can purchase a complete rebuild kit like that, and fix it with it, however the clutches are inside drums and in order to replace them, you need to disable it and reassemble it and really require the correct transmission tools to do so.

Although you should do the whole transmission, you can just pull the pump off and the first drum and the clutch is in that drum, and not have to pull the rest of the transmission apart, however you do risk putting it back together and having other issue's soon after, you need to be spotless clean with everything.

macman · 19-03-2012, 01:00 AM

I've read some links between gearbox electronic issues and coolant damage, especially regarding leaks from the heater tap onto the plugs where the engine bay loom meets the transmission loom as well as damage from coolant straight down the back of the engine, down the gearbox and onto the inhibitor switch. Apparently coolant can be reasonably conductive/damaging to electrics? Interestingly enough, the loss of manually selecting 1st or 2nd to engine brake developed straight after a severe coolant leak (about 2-3L of coolant SHAT out the expansion tank when I was out). Driving home straight after is when I noticed the issue had appeared. Whether that's what's happened or not, I can't say at this stage but I will definitely start by cleaning some more connections and completely removing/cleaning/replacing the inhibitor switch.

When that yields no results I'll be looking to rebuilding the gearbox with one of these ebay kits.

Timing isn't great as I'm completely without a car if the TS50 sells while my TE50 is still out of action. Also, up until recently there was an AU3 XR8 (220) on Gumtree being wrecked locally - with a full 6 speed manual setup, already removed and ready to go for 3k... Would have been a nice escape route.

Thanks for your advise/expertise 5.0 ED. I appreciate your confidence in ruling out the inhibitor switch and am not dismissing what you're recommended. I have access to another 'known good' switch so for my own satisfaction must try it first. When I post back confirming it's made no difference, things will be getting serious!

Dave.

Mr Hardware · 19-03-2012, 10:32 AM

Yeah i can understand from the ESS perspective. I switch between 3rd and 4th all the time, and mine catches 3rd perfectly. 2nd and 1st it doesn't want to know about unless you're on the power. Six years now it's been like that (half the car's life) and the rest of the automatic has been perfectly normal the whole time. And i don't baby it.

macman · 19-03-2012, 11:30 AM

Interesting how your gearbox is behaving in exactly the same way. D to 3 and it catches 3rd perfectly just like you said however it's just 3 to 2 or 1 and it just hits neutral until you blip the throttle then it comes back. Otherwise it shifts perfectly up/down automatically and always has (except once it didn't want to find reverse when I was parked on a hill but that was a year or so ago)...

I've always babied my TE50 (and my TS50) and I very rarely drive them "hard" except on an occasional skidpan day etc otherwise it's just daily commuting to work at 60k's in traffic.

Incredible that yours has been like it half the cars life and is still quite happy. Gives me some level of comfort!

fisherperforman · 19-03-2012, 12:14 PM

no engine braking in manual 1 is clutch 4 fault.might be time for rebuild

macman · 19-03-2012, 09:45 PM

Swapped the inhibitor switches over - both were in good nick and made no difference. Left them where they were (one from the TS is still on the TE and the one from the TE is still on the TS) - no point swapping them back.

Also noticed, the TS has a heat shield over the area, the TE doesn't (probably fell off).

Someone recommended to me to go to a trans specialist in Ashfield so I'll be heading there tomorrow to see what he says it will cost me for a rebuild. If it's over $2,500 I will be seriously considering wrecking the car. I love my car but I CANNOT afford to spend any more on it and I STILL need to sell the TS50 - it's got nothing wrong with it and one wants it for 10k so who's going to buy a TE50 with a bung gearbox?

Thanks 5.0 ED and fisherperforman, you were both right. And everyone else who has taken the time to advise/comment, thank you too.

I'll post up tomorrows results.

Mr Hardware · 20-03-2012, 10:55 AM

macman, i'll give you $5k for your TE with bung gearbox.

irdonn · 20-03-2012, 03:58 PM

macman .. I've used these guys a few times too. Opposite Welshpool train station, so easy to get home from.

http://www.transmissionmasters.com.au/contact.html

5.0 ED · 21-03-2012, 08:12 PM

Got any pic's/links to the car? Not sure how i would go about getting it here though lol.

macman · 22-03-2012, 01:01 PM

Calm down people... LOL... Plenty of pics online of both my TE50 and my TS50 (in the T-series showroom and the AU showroom).

It's all back together and I'm driving it to work again. After the trans fluid change it just feels soooo smooth. Just have to remember no 1st or 2nd when shifting manually.

Also the pinging seems to have gotten worse so I'm just driving VERY gently to avoid it at the moment. Still need to fit the new camshaft synchroniser which will hopefully address this issue.

Didn't manage to get to the workshop before he closed for the day on Monday. Tuesday and Wednesday were out of the question. Will try and get there for a "diagnosis/quote" this afternoon.