Member Since: 17 Jul 2012
Location: West Yorkshire
Posts: 131
The Megatronic Valve Body is the gubbins that does all the gear changes by operating valves that sends hydraulic fluid under pressure to various parts of the gearbox to push things around.
It is basically an oblong block with lots of channels and actuators in it. On top of the block a metal plate goes over it and it's bolted (I think) onto the gearbox - I picked this up when I had mine rebuild, so I may not have understood all of this perfectly, but it's my understanding anyway.
The oblong block does not have a normal type gasket to seal the pressure, but around the top of the block all the channel tops are sealed by a small embedded bead of silicone so that the flat plate, when bolted up, makes a seal.
What can happen is that if you run the gearbox for too long without an oil change (every 30K miles as suggested) then the breakdown of the oil can result in wear to this silicone bead and holes to be blown through it. As this gets worse the leaking of pressure from the hydraulic fluid can result in not enough "oomph" to move things properly.
Typically this this manifests with the torque convertor failing to lock up at lower revs. If you get the revs up, you increase the pressure of the fluid, overcoming the leaks, which does force the TC to lock up.
The slipping TC causes the plates in the TC to rub against each other and polish them to a glass like surface which makes the slip more likely. As the TC slips, heat builds in the transmission fluid which degrades further.
It's a bit of a vicious cycle.
The recon of the TC or new TC will likely use better quality plates and will lock up even if you have poor seals around the channels. It's another chunk of cash to get the valve body re-conditioned on top of the work you have had done.
I decided to get mine done, on the grounds that I was looking to keep the car for the longer term.
I'm not sure I made the correct decision, since other problems on my towing trip to Millau have dented my confidence in the D3
The CPU can be seen in the second shot - bottom left corner, under the spring type thing.Mark.
2006, D3 SE Auto - gone but not forgotten.
2014 BMW 530d M Sport Tourer.
1977 Triumph Spitfire 1500
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Disco Picture Website Here
22nd Aug 2014 5:17 pm
ids
Member Since: 12 May 2009
Location: Herefordshire
Posts: 384
Mines now in at VMTP
I had a BAS remap a while back and suspect the extra torque has finished the TC off for good. My motor has done 180K now so I suppose thats not bad.
It got to the point where driving from Telford to Cannock I had to pull over 4 times as it kept going into F mode (stays in gear it seems)
Initially mine started not being able to change (it seems in about 4th up to 5th) and had a surge of revs as it could not change. I also had had the usual wobbles up hills as well as some noise (squeal) when changing.
Driving a POS 2005 Astra at the moment as a loaner from them... hoping it will be back soon. Modern hatchbacks are pure misery.........
2nd Sep 2014 2:26 pm
Mambosasa
Member Since: 31 May 2013
Location: Birmingham
Posts: 226
I may see yours there tomorrow. Going to get the ECU re-set. It seems to have issues engaging 5th gear. Clunking into gear, then juddering until its out of the 'pull'. Hopefully the resetting the controller/ ecu will resolve it.D4 HSE all the way
2nd Sep 2014 6:49 pm
Blobby
Member Since: 28 Feb 2009
Location: Gloucestershire
Posts: 277
I'm also going back to VMTP (on Tuesday) both for the required 1,000 miles checkup on the TC and gearbox rebuild and for them to identify why my rebuilt transmission now makes strange loud noises as it changes up/down - enough to make people turn and look in the street. It changes gear perfectly and the strange noises can be minimised with adaptive throttle control but something isn't right and it's driving me mad. I'm even looking forward to having the 2005 Astra loan car back.
2nd Sep 2014 6:58 pm
ids
Member Since: 12 May 2009
Location: Herefordshire
Posts: 384
The fella on reception seemed to know what he was talking about about it needing about 30 miles to calibrate it. But with two people going back that makes me a little concerned.
We shall see I guess.... However it doesnt take long for a reputation to spread so lets hope all three of our issues are sorted.
You are welcome to the Astra. It really is . Check out the sunglasses that have been left in if you get it. Proper Bono jobs.....
Ids
2nd Sep 2014 8:39 pm
Blobby
Member Since: 28 Feb 2009
Location: Gloucestershire
Posts: 277
Think the 'fella' on reception is Nigel and he seems to check-drive the cars.
The 'sunglasses'. I wondered what that little box was too. Wasn't tempted to wear the jewel encrusted sunglasses even though I was driving into the sun. I did pump the Astra's tyres up though as one was down to 6 psi. It's speedo is also hugely inaccurate as checked it against GPS as everyone was overtaking me on the motorway. When it says you are doing 70 you are really doing about 63.
Likewise, I REALLY hope they get all our issues sorted. I paid them £2.1k. Don't mind paying the money so long as it works well afterwards.
2nd Sep 2014 8:50 pm
incubus13
Member Since: 02 Feb 2014
Location: Bourgas
Posts: 17
Where can I buy these solenoids? I need the yellow one. I find them only in USA, Russia and China sites... Something UK or EU? 8)
5th Sep 2014 1:58 pm
therealboss
Member Since: 21 Mar 2014
Location: Co Carlow
Posts: 1958
After reading this thread I'm so happy I decided to go to Bristol Transmissions, fingers crossed it's all working a dream, very smooth changes and now getting better MPG.
Member Since: 12 May 2009
Location: Herefordshire
Posts: 384
I have now had mine back from VMTP
Pleased to say all is well and it drives perfectly now. Along with the TC I had the sump pan replaced with a metal one with the removable filter.
I also had to have a new clutch drum, plus the output spine was damaged so that was replaced. They also found issues with the valves but swapped mine for another they had and sorted that.
Best part of £2.6K so those who don't look after their transmissions beware !
Ids
16th Sep 2014 7:01 am
manwithhabits
Member Since: 25 Sep 2012
Location: Doncaster
Posts: 31
I had my gearbox done a few months ago - new TC, new clutch packs and seals the whole lot, including a new Mechatronic as mine was 'a bit worn' and just wasn't able to build up pressure. This is what resulted in the car not liking the idea of first gear, but requiring a significant amount of oomph to give up and go for second - and all the resulting torques hitting the rear prop shaft all at one probably explained the sudden demise of the centre bearing.
Still having shudder issues, and think this is now going to be the clutch pack in the transfer box. Going to drain, flush and refill with new oil and a tube of the red stuff and see if that helps - even if it's temporary. At least then I know what I'll be spending more oney on!!!
18th Sep 2014 8:22 pm
Mambosasa
Member Since: 31 May 2013
Location: Birmingham
Posts: 226
Let's see what they say after they drop the gearbox down again. I hope they sort it out.
The bling sun glasses are still there. My drive to work today was 'fun' D4 HSE all the way
18th Sep 2014 9:36 pm
Snowonthehill
Member Since: 31 Aug 2015
Location: Oswestry
Posts: 1
Torque converter judder
Appear to have the same problem. Revs fluctuating under load, initially only in auto, now also in manual. Judder from drivetrain on pulling up in lower revs.
Has anyone had the torque converter replaced in/near shropshire, any recommended addresses?
31st Aug 2015 8:47 am
Mambosasa
Member Since: 31 May 2013
Location: Birmingham
Posts: 226
Well, mine has gone back in. They tell me that the TC is slipping again. But this should still be under the warranty period.
Interestingly they seem to suggest that what I had in was a recon TC not a new one! At £2.5K I thought I was getting a new one. Surely it can't be so. D4 HSE all the way
2nd Sep 2015 11:58 pm
Barn1e D3 Decade
Member Since: 28 Aug 2006
Location: Mid-sussex
Posts: 2021
For a TC replacement I would say £1000 is about right price. £2500 if including a autobox rebuild. As for the TC being refurbished I think that is common and I doubt you end up with an inferior product if from reputable supplier. I used Autogearboxes in Hailsham in Sussex. Their sister company next door manufactures the refurbished TC and seems to supply Parts of UK. Traditional engineering and fun to watch.2005, TDV6 S, Auto, 190k miles, owned from new, V8 Brake Upgrade, Nancom Evo, RLD protector, BAS EGR blanking & Remap, separate ATF cooler, changing all the fluids ahead of time.
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum
. Check out the sunglasses that have been left in if you get it. Proper Bono jobs..... 
