Mk2 3000 S Auto - Auto box warning me?

[slybynight]

Got the car started the other day after a cold 4 months in garage. Pumped up tyres, checked oil, water etc. All good. While reversing out from garage, just lost all drive. Engine carried on fine. Put in N then back into R, no power to the wheels. Put in P then R... still nothing, tried D... nothing there either. No grinding felt through selector or horrid noises, no change in engine revs. Heart sank. Tears appeared in eyes. Tried it once again for luck and ..... everything fine - after a bit of testing, took her out for a lovely little drive. No problems.

It has never done this before. Should I change transmission fluid? What should I use? Is this doable myself? Was it just a long winter issue? Is my box on the way out?

Any advice welcome.

[D366Y]

I've had a similar issue with my auto dying randomly before - I changed the fluid (and filter while I was there) and *touch wood* not had the problem again but obviously can't guarantee it will work for you but was easy enough to do so would recommend trying it.

Depending how handy you are it's not massively difficult...
Obviously I'm guessing you know how to check the fluid - if not it's the red(or black depending on the year of your car) dipstick that isn't the oil and should be between the two notches.

If you jack the car up or get it on ramps or whatever, at the bottom of the gearbox is a large flat rectangular panel (the 'pan'). Unscrew the bolts holding it on and the lovely transmission fluid will start to pour down your arms and all over your face. Amateurs use a bucket or similar to catch this but I'd rather just bathe in it.

The filter is the next thing you'll see underneath which from memory has 3-5 screws or bolts holding it in place and is the large rectangular thing you'll see once the 'pan' has been taken off the bottom - you don't have to change it but if you don't know whether it's been done before it's a good time to do it.

Once the filter is changed (if you're doing it) or simply all the oil has drained out, get the new gasket for the pan, add a bit of sealant if you feel like it for good measure, and tighten back up again to the correct torque - don't overdo it otherwise the lip of the pan will get distorted and start leaking.

Once screwed back up, top up with fluid down the dipstick tube for the gearbox - job done.

[slybynight]

.. job done.

Hey thanks @D366Y - very informative.

[Mr B]

The only time I've ever had what you describe is when the fluid is low in the slush box.

If the fluid is low and there are no visible leaks then the vacuum modulator may have failed, I won't pretend that I know what it really does but I do know that if it fails it allows the engine to suck tranny fluid out of the auto box to be burnt in the engine.

The fluid on the dipstick should look a lovely cherry red, if its slightly brownish it's time to change it, just dropping the sump pan doesn't empty out the torque converter though, there is a great video on YouTube on how to change the fluid with the engine running which will drain the torque converter - you can literally see the fluid changing colour as the old fluid is removed and the new fluid is going in, the torque converter does have a drain plug but you need to remove the starter motor to get to it.

Hope this helps

Wayne

[slybynight]

...Hope this helps...

Thanks @Mr B - very helpful - Good bunch here!

[D366Y]

The fluid on the dipstick should look a lovely cherry red, if its slightly brownish it's time to change it, just dropping the sump pan doesn't empty out the torque converter though, there is a great video on YouTube on how to change the fluid with the engine running which will drain the torque converter - you can literally see the fluid changing colour as the old fluid is removed and the new fluid is going in, the torque converter does have a drain plug but you need to remove the starter motor to get to it.

Hope this helps

Wayne

Good point Wayne - I forgot about the torque converter entirely!

[Lord Flasheart]

Also, to check the fluid level properly, the car should ideally be warmed up & the shifter moved through all positions a few time, after a run would be best,s & check the level while the engine is running.

Totally different to checking the engine oil level when the engine is off & been standing for 5-10 mins

As mentioned, the colour of the fluid is crucial to understanding if it needs changing or just topping up.