Which gearbox?
- Thread starter Hooley
- Start date
timmus
A2OC Donor
Yes, this discovery process is very exciting
I will find out on the 2nd of April
Absolutely! The fact that this option has suddenly sprung up is exciting. I'm already considering talking to a friend of mine with an A2 who doesn't want the longer 5th but can't afford the 6th gear. Whatever the outcome of the JDD 'box, a way of extending all gears proportionally seems to have been found.
It's clear that I have my doubts about the JDD per se as a workable solution, but to a degree I am playing devil's advocate. As Simon said, the A2OC is a sounding board for new ideas, and challenging ideas helps to separate the good ones from the bad. I do agree that Simon argues the case in favour very well, and I do hope this works out!
Tom
Edit: Just as an aside, Mike Skipton fitted my longer 5th. Including all parts, new BlueMotion oil and Mike's time, I was charged £295.
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Hedge
A2OC Donor
I was quoted over 400 by Stealth. Kinda put me off.
Cheers, Hedge
Tom, I suppose that we're all lucky in that you don't have a TV and that you have the time to help us, as you do! LOL! I am a bit surprised, however, that this time, you have neglected me! Well, just a bit! I need the answer to my question regarding changing the 6th gear ratio on the 6-speed box that "Spike" had deemed to be a suitable replacement for our 5-speed? ( that was just a few posts back) So, MASTERMIND, help me there, please? I like my idea as a cheap way to a 6-speed box! Until, that is, it is "blown out of the water"! LOL!
David
David
Some information on that 6-speed gearbox that might be suitable for the A2 ..... Type O2S, code GQM. From :- VW Golf, 10/03 > 05/06. The 02S is also known as MQ250-6F -- the "250" probably refers to its torque rating (in Nm), although that is not true with all VAG gearboxes. It also sometimes is incorrectly referred to as an 0A4, which is a 5-speed. (That's 0A4 -- not 04A, as one would expect.)
I have located a fully refurbish box for £795 + V.A.T. I'm sure that a cheaper box can be found ....
David
I have located a fully refurbish box for £795 + V.A.T. I'm sure that a cheaper box can be found ....
David
I don't think its going to be cheap. A GQM box from a breaker is around £650 ( http://www.ebay.co.uk/itm/VW-Golf-M...arts_Vehicles_CarParts_SM&hash=item4ac269066f
This and your donor box both need to be stripped and the clutch housings, speedo drive and driveshaft flanges swapped. In the process the final drive assy will need shimming to set the bearing preloads. Add in replacement seals, gaskets etc and the rebuild could easily cost £500 with removal and replacement of the gearbox from the car another £200 (plus vat on these 'best guess' Stealth prices)
Total so far is £650 + £600 + £240 and this is without any upgrades to the 6th gear ratio. Assuming there are gears available for a taller 6th, parts plus fitting would add another £300+ to the bill
Cheers Spike
timmus
A2OC Donor
Easy now. Yes, I'm willing to speak my mind and I think I express myself well in written form, but I nevertheless defer to the superior knowledge of other members here.
Ok, so I've had a bit of a look into this. The 02S gearbox is very, very similar to the 02J gearbox in the A2.
As an aside: From what I've seen, I suspect EuroTuning's 6-speed conversion kit was inspired by the design of the 02S 'box. In my research, I've actually found a few different companies who offer conversion kits similar to that made by ET.
Let's assume that the issues that Spike describes can all be overcome, admittedly at huge cost, and that the 02S can be fitted to the A2...
The 6th gear in the 02S is either exactly the same as the A2's fifth or fractionally longer (3.5%), depending on which exact model you use. This results in a phenomenon I described way back in this thread, where you've got almost too much gear flexibility. In other words, the gears are a bit too close together. It's great if you're doing some spirited driving on country roads, as you've always got a perfect gear for every speed, but, a lot of the time, it just results in changing gear all the time. My parents' Touran has the 02S 'box, and I find that I skip gears frequently, mostly when changing down.
Would I go to the expense of having this in my A2? No, absolutely not. I would rather have 5 gears spaced as standard than have 6 gears in the same total range.
Ok, so let's do as you suggest and replace the 6th gear with a longer gearset. It turns out that this isn't possible, but let's assume it is...
You'd end up with 5 gears for urban and cross-country driving and a 'longer 6th'. However, the first 5 gears would only occupy the range of 4.2 gears in the A2. So, you'd basically have exactly the same drawback as the 'longer 5th' setup, except you'd have 5 gears below 'the gap', meaning lots of gear changing from 1st to 5th. I'd honestly rather keep things simple and have a longer 5th.
It seems you can't actually do this for two reasons. The first is that a longer 6th gear needs a larger driving cog, and that would argue with part of the selector mechanism; the rocker. The second reason is that the 6th gearset sits on the very end of the gearbox shafts. If you fit a longer 6th gear, the driven cog gets correspondingly smaller, making the gear 'heavier' and increasing the forces on the gearbox shafts. If you have a heavier gear than intended on the very end of the shaft, furthest away from the clutch, you significantly increase wear and the risk of bearing failure.
This is where EuroTuning's kit is so clever. Unlike most of the 6-speed conversion kits, it does away with the rocker part of the selector mechanism. This kills two birds with one stone. The larger cog obviously can't argue with a rocker that's been removed, and the loss of the rocker means that 5th and 6th gear have to swap places. In other words, whereas an 02S gearbox orders its gears 1-2-3-4-5-6, an 02J converted to 6-speed has its gears ordered 1-2-3-4-6-5. Consequently, the longest, heaviest gear is no longer on the very end of the shaft, meaning it is supported evenly by the bearings and much longer gears can be used whilst keeping the forces within VAG's stated limits.
Most 6-speed conversion kits can't offer anything longer than a 0.75 gearset, meaning they're only suitable for converting the gearboxes of petrol-engined cars, where 0.75 would be considered a 6th gear. EuroTuning's kit solves the problem for us TDI owners who've already got a 0.75 5th as they're able to provide ratios we'd consider suitable as a 6th gear.
Cheers,
Tom
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Thanks Mike, 10% will do for me
I would get an extra 30-40 miles for every tank!! Cheers Spike
I wish I had never asked now...
J
Why? Is it because your going to be £500 lighter?
I agree Tom, if your idea cannot endure a little examination then it's not worth pursuing.
IMHO, there is a lot of potential in fitting the JDD gearbox into an A2
If you look the specs of the BlueMotion/Ecomotiv/Greenline VAG group cars (all using the JDD box).
You will see that they are heavier and have a higher aero drag than the A2's.
But they are using the same engines (with a few updated components, ECU etc)
These cars are touted as contemporary eco marvels (even beating the mighty Pirus at the eco stakes) and return as such, amazing MPG/emissions etc.
OK, they now have a few new tricks to eek out more MPG, like stop/start etc. But, we could do that too, with a twist of the right hand!
But weight saving/aero measures are always the first things you should look at, when trying to get more performance/economy (look at F1 car development).
We all know the A2’s weight/aero advantages, so in theory, the A2 with a current eco/longer gearbox could match the latest eco ‘green’ cars?
What I love about this:
If you were to go into a VW showroom and buy a BlueMotion with a similar spec to the Audi A2 SE, it would cost you nearly £17,000.
For that, you could walk out thinking you were a ‘green’ person and had just done your bit for the environment, and your wallet!
Or you could buy a ‘recycled’ A2 for a 1/7th of the price and with a few tweaks get similar running costs!
My bet is...the A2 will last longer and not to mention it's better looking too!
For all the people looking at alternative gearboxes that might fit the A2.
Here is a list of engine codes to check out AMF, BHC, BWB, AMS, BAY, BMS, BNV.
These engines with compatible(?) gearboxes are used in a lot of VAG group cars, here are some:
VOLKSWAGEN:
LUPO 1999-06 MODEL YEARS (6X/6E 3 CYLINDER) WITH ENGINE CODE - AMF
POLO 2000-02 MODEL YEARS (6N2) WITH ENGINE CODE - AMF
POLO 2002-05 MODEL YEARS (9N) WITH ENGINE CODES - AMF, BAY
POLO 2005-10 MODEL YEARS (9N3) WITH ENGINE CODES - BNV, BWB, BMS
SEAT:
AROSA 1997-04 MODEL YEARS (6H) WITH ENGINE CODE - AMF
CORDOBA 2003-05 MODEL YEARS (6L) WITH ENGINE CODE - AMF
CORDOBA 2006 MODEL YEAR ONWARDS (6L) WITH ENGINE CODES - AMF, BNV, BMS
IBIZA 2002-05 MODEL YEARS (6L) WITH ENGINE CODE - AMF
IBIZA 2006-2009 MODEL YEARS (6L) WITH ENGINE CODES - AMF, BNV, BMS
IBIZA 2009-10 MODEL YEARS (6J) WITH ENGINE CODES - AMF, BNV, BMS
SKODA:
FABIA 2000-04 MODEL YEARS (6Y) WITH ENGINE CODE - AMF
FABIA 2005-08 MODEL YEARS (6Y) WITH ENGINE CODES - AMF, BNV
FABIA 2007-10 MODEL YEARS (5J) WITH ENGINE CODES - BNV, BMS
ROOMSTER 2006-10 MODEL YEARS (5J) WITH ENGINE CODES - BNV, BMS
Please use as reference/starting point, do your research to check compatibility with your car.
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Tom! .... That "Mastermind" comment was just a bit of light-hearted fun, and a reference to my earlier post, which was also meant to be taken in a comical vein! That aside, you DO have so much knowledge and are willing to give a lot of time to helping others on this Forum! AND, as I know from meeting you, you are also a very friendly and pleasant Guy! I would never mean to offend anybody! .....
David
David
timmus
A2OC Donor
timmus
A2OC Donor
You're absolutely right, Simon, and this is just one of the many reasons I love the A2. Sat on the motorway, my A2 is capable of 80mpg.
It's bigger, better looking and better to drive than a BlueMotion, but also has OpenSky, aircon and auxiliary heating, Bose, full electric glass, Sport seats and a raft of other weighty luxuries. Other cars might be catching up with the A2 TDI where the raw economy figures are concerned, but with other factors taken into account, the A2 is still king, 15 years after its design.
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timmus
A2OC Donor
I'm afraid I didn't spot anything suitable for the 02T gearbox, Bruce, so the petrol-powered A2s in the ranks are still limited to 5 gears...
MikeMarsUK
A2OC Donor
Thanks Mike, 10% will do for me
...
The saving is all as a result of the RPM drop (lower RPM -> lower engine resistance & a better area of the BSFC chart).
nuttinnew
A2OC Donor
No problem Tom, in the big scheme of things it's irrelevant with the output from a 1.4 petrol, and their 5sp is about the longest geared off-the-shelf anyhow (I'm not sure what box a 5sp 1.2 tsi uses). A Lupo 6sp could probably be used, but if I was going to change box in it I'd rather a 6sp auto or dsg
Aero tweaks are still possible, and I'm sure 1.2 arches would cover standard 16" SEs without problem (though I'm sure my A100-capped steels would be better still for aero).
Aero tweaks are still possible, and I'm sure 1.2 arches would cover standard 16" SEs without problem (though I'm sure my A100-capped steels would be better still for aero).
timmus
A2OC Donor
There's one synchro sleeve for 1st and 2nd, and another for 3rd and 4th. Chances are that the 3rd gear synchro ring is a bit chewed and that the sleeve (that's shared between 3rd and 4th) is also worn on the 3rd-gear side. Third gear does seem to be the common problem for 02J gearboxes. When Vince reconditioned mine, third was the worst... though I wasn't suffering from problems anything like as bad as you describe. As you know, my recondition was brought about by a badly worn diff', possibly because the previous owners didn't change the front tyres as pairs.
Tom
dan_b
A2OC Donor
I've never really understood how gearboxes work to be honest - but the 3rd/4th having the same synchro seems to tally with my experience - 3rd to 4th can also often be a bit tricky if 2nd to 3rd has been a bad one, but usually a bad 2nd to 3rd will alert me to be doubly careful!
It's interesting that Hooley started also getting issues going into 5th - I presume then that 5th has its own synchro as well?
It's interesting that Hooley started also getting issues going into 5th - I presume then that 5th has its own synchro as well?
timmus
A2OC Donor
Hi Dan,
Have a read of this thread... posts 3 & 4 in particular should increase your understanding of how a gearbox works: http://www.a2oc.net/forum/showthrea...on-and-6-Speed-Conversion&p=165094#post165094
Note that synchro sleeves and synchro rings are not the same part. Each gear has a synchro ring of its own, though each pair of gears shares a synchro sleeve. Because the 02J 'box has an odd number of gears, 5th gear has a synchro sleeve all to itself.
Once you've had a read of the posts I've linked, have a look at the annotated photo below. It shows 5th & 6th gear as a pair to either side of their synchro sleeve. The same arrangement is true for 1st & 2nd, and 3rd & 4th.
As the synchro sleeve moves towards a cog when you select that gear, it first meets the synchro ring. This causes the cog you're trying to select to spin at the same rate as the synchro sleeve, allowing the synchro sleeve to move over the cog's dog teeth, thereby locking that gear to the spinning shaft within. Sorry, it's difficult to explain with words alone.
If a particular synchro ring is knackered, this rotational speed matching no longer works properly. This means engaging and disengaging that particular gear can be difficult, and can be accompanied by crunching noises as the synchro ring and the cog's dog teeth fail to mate properly.
If you've got issues going from 2nd to 3rd, and from 3rd to 4th, the issue is almost certainly with the 3rd-gear synchro ring.
I hope that makes sense.
Tom
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