MYP Gearbox 1.4tdi AMF (75) 6 speed MMXXIV

[rotifer II]

Introduction​

Hi All,

A little background on why it's time to install a six-speed gearbox. Since June 2020 a MAL geabox has been fitted to the remapped 75-hp TDI.

After a fair few years of operating this quirky MAL gearbox, it's time for a change, when shifting gear quickly between third and fourth, it crunches. However, add a pause in the gate before selecting fourth gear, prevents the crunch.

After rebuilding cylinder head in January, the car spent all summer gathering cobwebs waiting for a (cheap) 6-speed MYP gearbox. Finally found one last week in Liverpool for £207 with a 30-day money-back guarantee, so I bought it.
The next day, in my newly built tiny workshop, I checked over the case's exterior for cracks and the bolt hole threads, everything was fine.

To improve the tired gearbox the easily accessible, worn-out parts will be replaced before fitting the box to the car. These include the shifter tower bearing, guide tube, ball stud, clutch release arm and release bearing. I hope the internal gear cogs, synchromesh parts, and bearings are not worn out. I think there is backlash (freeplay) in the gears, but if everything works out ok in the end with a couple of oil changes, I'll call that a win.

When emptying the glitter-laden treacle from the MYP drain plug, I thoght this is not good, plus it was a bit short of the recommended 2.3 litres. (I find out later why that was, spoiler see last image) The levers, gearbox end cover, and tower selector were removed. The tower selector proved difficult to disassemble, the steel pin in the aluminium case was stuck fast. A rotary tool and die grinder attachment (slowly) cut the toughened pin. Once dissasembled I discovered the MYP selector had no tower bearing. Could it be how they were designed? I don’t know. There is a lot of side-to-side play in the selector tower. I must check to see if the MAL tower fits the MYP box.
Inside the gearbox end cover there is a magnet, which was caked up with grey paste, I cleaned it, clipped it back into place.
In the next couple of days I plan to remove the bell housing, look for more magnets and take a few photos of what I find.

A thank you​

I recognise and thank all of you who have taken any part in previously documented MYP 6 speed conversions shared on A2OC. I will attempt to credit those whose information I have read and reused.

All the best



EDIT 22/09/24

Drained the remaining gear oil following the workshop manual instructions.

 

[TAABVW]

I have fitted an MYP to a couple of A2's. One of them has very similar crunching from odd gears to even gears. I have tentatively concluded that the crunching is actually coming from the connection at the bottom of the gear stick and not the gearbox at all. The evidence for my conclusion is the crunch sets one way and then the other (forward and back on the gear stick). So for example if it crunches into 1st and I miss gears and go 1st to 3rd to 5th, then I get no crunching going into 3rd and 5th because the crunch is "set" forwards (on the gear stick). The same if I "set" the crunch in the even gears. But going forward and back on the gearstick (odd to even or vice versa) the crunch is continually being "reset". A pause in the gate allows time for the sychro to spin up thus requiring less pressure on the gear stick and the crunch set can be avoided.

I mention this in case your new MYP still exhibits a crunch when fitted and in case any others can tell me if my tentative diagnosis is correct.

 

[rotifer II]

Hi, @TAABVW.

A theory right from the start, great stuff.
My gut feeling is the internal gearbox selectors are worn/need adjustment. I'm at the beginning of my journey to teach myself how the bits inside the gearbox do their job.

EDITED 25/09/24 (taught myself a little more)
Thinking about replicating your observations on other gearboxes, hypothetically, if a schematic (map) of the movements of the Bowden cables (left and right) (up and down) and how they move the relay lever and the gear selector lever into the gears from neutral, a description can written down for all gears 1st to 6th and reverse detailing how each gear choice move the two cables and levers. This would allow gear combonations (e.g. first to third (odd numbers combination) or second to fourth (even number combination) to be understood and importantly conveyed to other folk. It should then be possible to test your observation on different owners gearboxes. A written methodology and a table to populate for each gearbox tested could be created. A tick in the table would indicate a crunch and a cross, no crunch. The table could have columns with different different speeds to change up or down gears at. Then others could follow the instruction/methodoligy and populate the table when taking part in the gearbox crunch experiment. A handy bar graph would show the results.

I like your "reset theory"; it makes sense.

I have a question: have you any ideas on how we might repair the crunch?

Great to hear from you.

 

[Robin_Cox]

I have fitted an MYP to a couple of A2's. One of them has very similar crunching from odd gears to even gears. I have tentatively concluded that the crunching is actually coming from the connection at the bottom of the gear stick and not the gearbox at all. The evidence for my conclusion is the crunch sets one way and then the other (forward and back on the gear stick). So for example if it crunches into 1st and I miss gears and go 1st to 3rd to 5th, then I get no crunching going into 3rd and 5th because the crunch is "set" forwards (on the gear stick). The same if I "set" the crunch in the even gears. But going forward and back on the gearstick (odd to even or vice versa) the crunch is continually being "reset". A pause in the gate allows time for the sychro to spin up thus requiring less pressure on the gear stick and the crunch set can be avoided.

I mention this in case your new MYP still exhibits a crunch when fitted and in case any others can tell me if my tentative diagnosis is correct.

Does it crunch if you move the gears at the counterweight above the selector (obviously I don't want to interfere with your gear-lever calibration but the obvious question would be to compare this with the gear cables disconnected / connected) to see if the crunch is at the gearbox end or the gear-lever end surely?

 

[Little Dog]

The words I immediately picked up on were “glitter ladened treacle”.
Ferrous debris tend to be dark grey and collect on a magnet. Glitter if it is non magnetic needs investigating.

 

[rotifer II]

Hello @Robin_Cox,

The MAL gearbox has the characteristics of a crash box between 3rd and 4th if the the gear change is rushed.
The link below is a youtube video of 3rd to 4th selected via the shift tower.


MAL 3rd & 4th

EDIT
The gearbox has no crunch when shifting the tower by hand.
EDIT 2
The crunch is definitely in the gearbox not the gear stick mechanism inside the car.

I am fairly sure the gearbox mounting bracket rubbers are worn out, which mess up the shifting accuracy.

I have a replacement.

 

[rotifer II]

Hello @Little Dog,

The magnet had grey ferrous material deposited on and around it.

The gear oil colour is shown on the white card above.

Link to a YouTube video of the oil.

MYP Gear oil​

 

[Little Dog]

If you are on Facebook I would run the picture of the oil past Martin Emment. There is nothing he doesn't know about VAG boxes, https://www.facebook.com/martin.emment?comment_id=Y29tbWVudDoxMDE1NjkyNDI4MDI0Njk1N18xMDE1NjkyNDg3NjIxNjk1Nw==&locale=en_GB
EDIT, that is his personal page, he also has a business page. It is the business page you want.

 

[rotifer II]

Hi @Little Dog, thank you for passing on Martin Emment's details. I do not have a Facebook account I closed it years ago and have not made a new one.

 

[TAABVW]

Does it crunch if you move the gears at the counterweight above the selector (obviously I don't want to interfere with your gear-lever calibration but the obvious question would be to compare this with the gear cables disconnected / connected) to see if the crunch is at the gearbox end or the gear-lever end surely?

For me there is no crunching when using the counterweight to change gear.

Reads like Rotifer is pretty certain his crunch is in the gearbox so perhaps trashed synchro. Anyway I will not contaminate his thread any further with my issues.

 

[rotifer II]

Please keep your issues coming. (EDIT) I do not see them as issues at all. 22/09/24
It's all about gearboxes this thread and if a lot of us are suffering the crunch, so to speak, it would be nice to resolve it somehow.

Your input on the 1.4 tdi Struggling to start... was great.



Edit 22/09/24
Was looking at the photos of the gear selector cables in post number19-20 of the thread

Link
gear selector cables update

 

[rotifer II]

Thinking about the gearbox mount a little more, a worn mount should not make a difference to gear selection because the cable carrier is isolated from wobble as its mounted directly to the top of the gearbox.

 

[rotifer II]

Research​

Hi All,
The videos that Matt-98AHU posted to the TDI club forum in April 2023 are what I've been using as a guide to take apart the 6 speed MYP.

Available at the TDICLUB forum.

ClubTDI-Matt-98AHU​

The aim of their video is to demonstrate the transplant of the 02S gears into an 02J case.

For those who own an A2 with a mechanical vehicle speed cable setup, the swap has been done previously by @67boris post number 119.
You can see that Matt98-AHU has a background in gearbox work with access to various dedicated tools and a lathe.

I guess that A2OC folk will have the tools and know-how to do the same?

Anyway, after taking apart some of my own 02S MYP box, I've arrived at PEAK TOOL—that is, the place where my basic tool kit is unable to remove the fifth and sixth gear.

Here are my thoughts: I have bearing pullers of different sizes, but even if I were to get the gear cogs off, I have no way to press them back. The condition of gears inside the casing will be unknown until taken for a drive.
As I understand it, the 5th and 6th gear cogs need to be removed to split the casing. It is what I would have liked to do—remove only the bell housing, but as far as I can tell, it is not how the box was designed to be taken apart.

 

[rotifer II]

LINK: Workshop Manual​

02S gearbox manual

From post number 121
- New 6 speed gearbox method - passat '11 onwards MYP gearbox

EDIT
I made the mistake of thinking the bell housing could be removed without removing 5th and 6th gear and the synchromesh.

Which has left very little room to reseal the two halves.

 

[rotifer II]

Good Luck​

Hi,
I picked up an additional PTU gearbox from Oldham yesterday as I wasn't convinced about the quality of the MYP from Liverpool.

Owning two gearboxes made it easy to compare their condition and basic functionality side by side.
The PTU from Oldham is the better of the two. As the private seller of the PTU box provided the car's registration number so I could check the mileage, 146k Audi A3.
The Liverpool MYP business seller had no registration information due to the high turn-over rate? Advertised at 98k they box was taken from their business VW Passat.
When buying second-hand parts, it is luck, be cautious.

To summarise, the £440 plus time and fuel is a good deal for two six-speed boxes and also this was good experience/fun.



Look at the difference inside each cover; that is a hard 98k miles.

Note
I will keep the thread title the same even though technically it should now say PTU not MYP.

 

[rotifer II]

AI-What does it know?​

Just an experiment to see if an AI chat bot can create instructions on how to fit an MYP gearbox.

Here​

 

[rotifer II]

Gear Casing Exterior (Replacement Parts)​

The next job before fitting a gearbox would be to clean it.

With usual assortment of spray oil, scrapers, brake cleaner and rags.

The parts bolted to the exterior of the gear casing can easily be replaced and its worth checking these before refitting the gearbox.

Clutch guide tube​

Usually shows signs of scratches along the shaft, polished areas of ware, and possibly rust. I would recommend replacing this part as it has two functions. Not only does it act as the bearing guide but it also seals the oil inside the gearbox.

Clutch release bearing​

Another component that should definitely be replaced with a high-quality named brand. Cheap bearings are prone to vibration that transmits noise through to the cabin.

Clutch release fork & clip​

If you have a VW part that is in good condition, I would say that you can refit it, as the quality of these is far superior to that of non-VW items, and it should provide many more years of service. I will be reusing this part; you do need to check the level of ware in the location where it pivots with the ball stud and slave cylinder.

Reverse light switch​

Remove this and clean the threads check the ball bearing at the end moves freely. Grease the threads to reduce contact corrosion.

Ball stud​

These are so cheap, I would go ahead and fit a new one.

Radial Shaft Seal Shift Tower​

(EDIT 08/10/24)

Internet search for a radial shaft seal 15x24x6 you should find one.

For those who have not ordered seals before it just taken from the following dimensions
internal diameter (ID) 15mm outer diameter (OD) 24mm Height 6mm

You could use 6.5mm or 7mm for the height if you can't find 6mm one.

Differential Seals-Drive Flange​

Left and right seals are different.

 

[rotifer II]

Gearbox Casing​

The shift tower that came with the MYP box had excessive play the PTU box tower is fine. If you're looking to buy a 6 speed box I recommend finding one locally so you can inspect it.

Shift Tower​

There are no bearings in the shift tower, and none came out when draining the oil I don't know where they have gone, perhaps there weren't any? The two parts that make up the shift mechanism were not designed to be dismantled unless you cut through a fixing pin, which is what I did.

Possibly the sleeve had a bearing that has disintegrated? If the remaining piece of pin lodged in the aluminium housing could be pressed out along with the sleeve, then could a bearing fitted? I'll find out when I attempt this task later.
This reminds me of some kind of plan that Baldrick might concoct.

View inside the aluminium shifter housing​

Shift Tower Shaft​

Relay lever​

Gearbox Selector Lever with Damper Weight​

A white plastic block slider runs inside a metal channel located on the side of the counterweight. I cleaned this channel with fine wet and dry paper and gave it a coat of silicone grease for silky smooth gear shifting.

Casing Brace​

There is a brace fitted to these gearboxes, so I will try and fit it. I don't know yet if the gear cable carrier requires modification for it to fit, I'll find out soon.

 

[CrispyEdd]

Great clear layout and info thanks for taking.time to present the thread so clearly and straight forward. Great pics

 

[rotifer II]

Shift Tower Casing​

EDIT (01/10/24)
The split bearing bush measurement given below is wrong.
Please use the VAG part numbers to order OEM.

Had a go at removing the rest of the locking pin and split bearing bushing. It was much easier than I expected. The locking pin was driven half way with an alignment punch, and an old nail finished the job. The inner bush was pressed out using the bench vice and an 11mm socket.

Skoda Part Number 02T 301 209A (7-14 days order time £2.65 + Vat from Skoda main dealer)​

The diameter where the shim fits is 17mm. EDIT 18mm

The wall thickness of the worn split bearing bush is 0.88mm a new bearing is generally 1.0mm so here is the reason for the movement in the selector.
0.12mm + 0.12mm = 0.24mm It doesn't sound much but as you travel out along the selector, the movement at the end inside the gearbox will be a bit more than 0.24mm.

EDIT (09/10/24)
Thankfully, a split bush bearing lower tower bearing cap. This cap is bolted to the underside if the gearbox and usually has a big VW cast into the housing. You can see the golden colour of the bushing in the first picture.

Split bearing bush size

The casing has two sprung ball bearings opposite each other that grip the cup. One of the bearings had almost worn through the surface ridges of the cup. If I had a welder I would drop some weld in the low spots and angle grind them level with the existing ridgeline.

The pin is a necessary part of the gear selection mechanism slotting neatly into the cut outs in the cup.

I plan to use the hardened Dremel bit as the locking pin when rebuilding the tower.

With care, the components can be separated from each other.