Over the last few weeks, I've noticed that my autobox hasn't quite been "itself".

Not sure how to describe it, but something seems to "slip" when accellerating in high gears. Not marjorly - but noticable.

Eg travelling along at 60mph, at approx 2000 rpm, if I give it some throttle, (not enough to change down) the rev needle will go up, and the engine will rev a bit before it seems to think about putting any more drive to the back wheels. Then the revs drop back down, and it pulls the car along without a problem. I did think possibly I need to check fluid levels, if it's low it wouldn't build enough pressure, hence this slippage, right?! (I know little about Auto transmissions).

The Omega's covered 120k now, and the previous owner of the car openly admits he did a lot of towing, which I guess would have strained the box, maybe the fluid has lost it's effectiveness and needs a change??

I've been deciding for weeks whether or not this is normal behavour (I don't recall it on my other omega's), or if it's even an issue, however today when I was driving home from work:

I'd just pulled away from a roundabout onto an A road. I got upto about 55mph, and it had gone through the gears.. and suddenly the MID came up with a message in big letters: "AUTOMATIC GEARBOX"

It seemed to go into some sort of emergency (limp home) mode for the rest of the drive home, and would only start off in (third?) gear, and kickdown/sports mode was disabled.

When I restarted the car, It was ok and the message had cleared.

One thought I did have, is that my Heater Bypass Valve has been leaking recently, and I've seen water running off the bellhousing. Is it possible that, maybe some water has entered a sensor or some electronics in the box, confusing it and causing that error?

Or is it more likely related to the funny autobox behaviour I've seen over the last few weeks?

I'm aware that I only paid mokey nuts for the car really, and I've had a LOT of trouble-free driving with it, so I won't cry if it's terminal, however on the other hand, apart from a tyre and a steering idler it just walked it's MOT, so I really don't want to get rid of it just yet!

Any opinions on the ins-outs of this issue? Cheers all.

JamesV6CDX wrote on 15. Aug 2006 at 00:46:

Probably absolutely nothing related to your problem but you also get that message and those g/box symptoms if you leave the throttle position sensor off (when you've done a cam belt change!     )

Frankly, I would change the gearbox and cut out all the nonsense. It does sound like it may be knackered beyond the routine oil and filter change. A secondhand box should cost no more than £100 and make sure you get it from someone who can tell you they drove the car, not your average breaker.

I know a chap in Nottingham who supplies me with boxes. Not had a problem yet. PM me for his details if you want them.

Changing the box is not that hard, but will take a whole Saturday. You will need VERY good axle stands and 2 decent trolly jacks, not your £9.99 Halfords jobbers! Also a good socket and Torx set.

You are welcome to borrow my stands and jack and any tools you may need. Make sure you get an AR35 box. They are stronger than the AR25s.

Can you fit an AR35 to a car that was fitted with AR25.

I understand that its the Torque convertor and the ECU that control the shift points, so if you change these as well as the box, will it work?

James, I agree with RMB.

Does sopund like its more than a fluid change thats needed.

Yes you can change the clutch bands, but why bother, cheaper to replace the box. 120K is nothing for a Vx autobox, They not Renault autoboxes you know, with silly plastic gears!, so surprized it failed. Although the fluid change is 60k, but I doubt that mine has ever been done and its on 138K. If towing it will (obviously) increase the strain on the entire drivetrain, and increase the clutch band wear.

I would swap the Box, and if you can fit the AR35, then these were designed for the 3.0 V6, and the later 2.5 TD so can handle mopre torque. (But you will need the Torque convertor and the Gearbox ECU)

If you do have to get an AR25, make sure its from a V6 and not a 2.0, as the one for the V6 had more clutch ands to cope with the extra torque (agian, take the Tourque convertor too, shouldn't need the ECU if you have an AR25 allready).

Hello James - any news on having a gas conversion?

Hi Matey,

The reason I've held off, is obviously because of my Autobox.

Although I'd love to have LPG - I've had to ask myself the question - is it really practical, on a N reg high-miler with a scrape on the side and some rust, and starting to have probs etc.....

Or should I hold off for a bit, and save up for a nicer/newer Omega?

What do you think? I'd appreciate advice! Cheers

Tatty - fair enough - if you are planning to scrap yourself it may be worth doing if you don't mind throwing away about £20 - £30 of pipe, if you are selling for scrap or sell on - you will lose money.

You need to work out how long to pay off £800 with fuel savings.

A couple of years will pay for the kit and give you some nice savings.

Refitting is not that awkwards - move bits around