0A6 info thread

[486]

Top Post Dawg
Joined
Mar 1, 2014
Location
MN
TDI
02 golf ALH
AKA MQ500
AKA the meanest transverse gearbox available so far
500nm input torque rating, coaxial slave cylinder, 1.125" 26 spline input shaft, 6spd, 190 lbs dry
They're in the TT-RS, the tiguan, seat alhambra, audi Q3, and transporter vans from what I've seen.
I've got one of them, code LMU, through the free ETKA I've found the 1,2,4-6 ratios, but nothing on the final drives or third gear. If they're the same finals as the gasoline tiguans in the US, the overall ratios on this trans are deeper in first gear and taller in 6th than the EBJ/EGR 02J's first and fifth.
The only ones in the US with the transfer case output are in the TT-RS with tall final drives and very deep change gears.

Their transfer case box outer casing will interchange with similar application automatic and DSG transfer boxes, but the splined shafts are different.
I've got the automatic transfer box and it does bolt up nicely, but the spline interface with the differential carrier is larger diameter and finer spline on the automatic, no contact is made.
The stub axle for the RF drive axle stub that passes through the transfer box is also smaller in diameter so it does not engage the front differential. The outer spline on the transfer box that the RF inner CV fits onto is the same spline as the LF output.
If you do import one, make sure to get a transfer box as well, they're uncommon over here. :p
The transfer box gears are 17 and 27 teeth, with the 17 tooth one going to the rear drive, propeller shaft goes 1.5663 times wheel speed. Not a common rear differential ratio at all from all my googling. I've got the rear differential from a toyota matrix, 2.27 ratio and the overdrive unit from a 42RE, ratio .69, makes for something close enough to live with through different tires.

The input shaft spline is the same as a lot of GM and Ford applications, but they're all 10" plus clutch discs, and I'm looking for some 9" ones. They'll come across me eventually.
ETA: got a 7.25" quartermaster clutch coming, took a lot of figuring but it may well turn out what nascar folk call 1 5/32" might be what everyone else calls 1 1/8", if not then I'm out another $120. To be put into a 30lb or so pot flywheel. Have to figure out if the starter ring gear's similar to the other transverse 4cyl ones...
The bellhousing has no hole for the timing marks to be accessed.
Bell bolt pattern is the same as all watercooled 4cyl. Some have been adapted to VR6 motors.
They take a 240mm clutch, DMF of course.

So, anyone else have info on them? Ratios especially!
 
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Festa

Veteran Member
Joined
Aug 14, 2016
Location
South east uk
TDI
Vw t5 van
They do take more torque than 500nm and I've been running close to 600nm for a few years. The only problem is the rear bearing on the first motion shaft:( the shaft try's to escape out the back of the box either breaking up the bearing or spinning the bearing within the case. They machine out and insert a steel sleeve to save the case but there's no uprated bearings for this as there's not enough room. Some of the other lads with the same box are running upto 650nm with the dmf failing first, I'll speak to the people who repaired mine as I've just had new gears fitted on 6th so will see if they will know the ratio's. I have an jfs code box
 

[486]

Top Post Dawg
Joined
Mar 1, 2014
Location
MN
TDI
02 golf ALH
They do take more torque than 500nm and I've been running close to 600nm for a few years. The only problem is the rear bearing on the first motion shaft:( the shaft try's to escape out the back of the box either breaking up the bearing or spinning the bearing within the case. They machine out and insert a steel sleeve to save the case but there's no uprated bearings for this as there's not enough room. Some of the other lads with the same box are running upto 650nm with the dmf failing first, I'll speak to the people who repaired mine as I've just had new gears fitted on 6th so will see if they will know the ratio's. I have an jfs code box
Very interesting. I assumed they'd have as much of a margin of safety as the smaller boxes, where guys are running 1.5 times the rated torque through them with decent results.

At the moment I'm working on getting my transfer box to work. Tried finding one for sale that'll ship to the US, but the only ones I can find are 4 times what an A/T tcase here goes for, or DSG which I don't know if they'll interchange. Going to weld up the shafts and respline them on my metal shaper.
I'll try and take pics as the transfer box comes apart.
 

Festa

Veteran Member
Joined
Aug 14, 2016
Location
South east uk
TDI
Vw t5 van
Try kernow transporters on Facebook and I know he has a eBay shop as well so he maybe able to ship over to you :) he has various five and six speed boxes but the six speed are stronger. Seems to have a good rating for reliability.
 

[486]

Top Post Dawg
Joined
Mar 1, 2014
Location
MN
TDI
02 golf ALH
Okay, got some more info in.
Flywheel for this trans has the same 135 tooth ring gear as everything else on back to when VW ditched that wierdo inside-out clutch.
The input shaft could be called 1 1/8" or 1 5/32" depending on who your clutch manufacturer is. Basically, if it's 26 spl and fits chevies it'll fit this trans. My 7.25" quartermaster clutch showed up and turns out it's a triple disc, with almost no wear. Nascar throwaways are totally my price, $120, shipped to my door! Three plate, so I've got to call them and get their lightest diaphragm spring on the way, as that'll equate to a torque rating around 800 n/m, very much excessive, but I'm cheap and a set of "rally" friction discs to convert it over to twin disc would be $215.
The starter is the same as the 02M starter, so I can get one of those coming from car-part for about 50 bucks.
Gonna try and pack as much iron in the bellhousing as I can, guys with 1.8s run these with light SMFs, but they've got like 7:1 compression. :p

Oh, and the big 2.5" bearing jamb nut that holds the tiguan transfer case together is left hand thread.
 
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[486]

Top Post Dawg
Joined
Mar 1, 2014
Location
MN
TDI
02 golf ALH
So, been working toward making the auto tcase fit. Welded on a slug of steel and splined it to fit the trans' rear output. Or at least it'd fit if I'd counted the splines right. I counted 35 splines, twice. I cut 35 splines. Now I count 34 splines, twice. :c
Oh well, I'd welded on a piece of A36 and have been having bad thoughts about that for a bit now, so I'll try and get some more proper 4130 or something.
Oh, and on the little seal inside the splined tube, A/T uses 52x31x7, M/T uses 48x31x7, as the minor diameter of the splines on the M/T is 49mm, major is 53mm. AT is some fine spline larger than 53mm minor diameter.
Might put up pics in a bit, if I can get my ancient phone to take a SD card again...
 

[486]

Top Post Dawg
Joined
Mar 1, 2014
Location
MN
TDI
02 golf ALH
Suppose I should update this, if you buy an 0A6 starter you can't use the ring gear from the 02j, wrong tooth form, and incorrect spacing. I think the later ring gears are a few mm larger in OD, and the teeth on the starter are fatter, so the ones on the ring gear are narrower.

When swapping it into a mk4 car, your shifter cables will be too short, put the shifter box atop the trans tunnel, inside the car. I made a stupid complex crank arrangement to get them to reach. Pics in the twin disc thread near the end.


So far it's holding up to a ceramic twin disc clutch with an unknown pressure plate. Drop the clutch in too low a gear and you just about smack your head on the windshield, surprised the airbags haven't gone off.
LMU code is in fact a little deeper in first and a little longer in sixth, cruising at 65 mph and 2000 RPM with 195/65/15s
 
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[486]

Top Post Dawg
Joined
Mar 1, 2014
Location
MN
TDI
02 golf ALH
well, 20k miles in and it's still doing everything it should. Haven't yet figured out how I want to get power to the rear wheels yet, that'll hopefully come about soon.
Figure I'll quote some posts from my compounds thread with relevant info to this thread, reduce the data fragmentation a little bit.

All right, got together a new twin disc (details in sig) got an 0A6 trans from a tiguan, LMU code.
...

New trans in there.

underneath, where the Tcase should go.
The shifter cables are way too short, so I've got to cobble something together.
...

Skip a few steps and the first one's almost sorted. Going to turn the crank by a tooth on the spline to get a little more engagement from the plastic rod end to the actual shifter cable. Right now only about 1/4" of rings are grabbed by the plastic fingers.
...

stick welded, because that's all I got where the car's parked, 3/32" 6011s and 75A burns through a lot of stuff real good. Stack up the slag and it fills in.
...

Forgot the camera inside between trips inside to thaw the toes. Skip a bunch of steps and the crank is almost done, just gotta weld the last arm to the rod in this image. It's now welded and painted, drying as I type.
decided to use up my PTO at work, so the car came apart
I'm not sure if I'm reworking the atmospheric turbo position to fit the transfer case, or cutting the pistons so the coolant res stops pressurizing itself with exhaust. I'll figure out what I'm gonna do with my life eventually.:eek:
Motor mount I had no idea it was broken until it was mostly apart, in fact I'd just opened the hood for greengeeker a couple days before and took the airbox out to show off the shift linkage, neither of us noticed it was cracked a half inch open. :p
May as well walk out and take some pics of progress, gimmie a few...

dumped the motor out on the ground, thinking hard on studs for the motor mounts, def gonna do them for the dogbone bolts in the trans, threads are just about pulled out of the trans case, prolly helicoil them 12x1.75 instead of the 12x1.5 they are from the factory, haven't looked at what the engine mount bolts are threaded, I'd assume the same 1.5.
Dogbone has to be shortened with the 0A6, factory's like 8ish inches from the K-member flange to the bolt hole, new one needs to be 6.5", been meaning to put a real stiff bushing in the bolt end anyways. Maybe a rod end bearing, I do really like those things.

so much junk, no mo room
Atmospheric is either going angled out compressor inducer pointed toward the lf headlight, or just smashed up more parallel to the HP rather than angled down as it is.

...
Got a couple LF inner joints to fit the trans, the six ball style rather than the tripod ones. Outer spline on them is slightly larger than 1.25" OD, so much beefier than the little tiny spline on the tripods. For the outer CV joints, the bolt style have a much larger shaft spline than the nut style. The spline that goes into the hub is the same, you just need to shorten the bolt or it does get smashed on the end by the CV innards.
ETA: oh right, gonna try my hand at making some 4340 shafts and having them heat treated. Hope I can find a friendly heat treater...
 

[486]

Top Post Dawg
Joined
Mar 1, 2014
Location
MN
TDI
02 golf ALH
Got the 4340 ordered for the shafts, only local place that had it wanted 95 bucks, place in michigan wanted 50, shipped to my door, double you tee eff (is word filtered, oddly enough)
Some pics,

turbos off

...
So, got the motor together

fixed the problem of no timing pointer with the new trans

transfer punch marks from both sides of piston stop, .100" is 1 deg on this circumference. I only made a TDC mark, thought about making extra punches for a few degrees to either side, but why bother, pump timing is guess and check anyways.
some pictures of how the timing pointer is handled, with a lack of a timing pointer I had to make my own. Web between the two holes makes the pointer arrow and the punch marks from either side of a piston stop get measured out to put the zero mark directly in the center.

another look above the Tcase

The 4340 for the axles finally showed up, turned them down, splined them on the metal shaper and had them heat treated to 47RC. Really should have took pics of the process again, but w/e.
...
Now the center shaft inside the Tcase should be the weak point. Shame as it is only available here in the audi TT-RS so if it's broke that puts me outta commission for while. All the more reason to get the 4wd going soon.
bit more relevant posts, with transfer case on engine
Shame that I don't have too many pics of how it looks now, it is very crammed into the chassis, but it looks like even the transfer box output will clear the steering rack with the rubber doughnut joint that they use.

ETA: the no-VSS problem was solved with a 7 toothed reluctor wheel shrink fit onto one of the CV axles. Used a three wire hall effect sensor to act as the VSS and it's accurate enough with 195/65/15s

ETA2: further transfer case information, the DQ500 (big DSG) transfer box fits and the splines engage with the MQ500, the right side intermediate shaft is not gundrilled for the bolt that holds it in the differential side gear but that doesn't seem to affect anything. It instead uses a spring c clip for retention, when the press fit of the needle bearings are the real method of retention.
The automatic tiguan transfer box will bolt up, but neither shaft actually makes contact with their mating shafts.
 
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iwannajettatdi

Veteran Member
Joined
Jun 17, 2003
Location
Salem, OR
TDI
2015 Brilliant Black Audi Q5 3.0TDI, 2014 Tempest Blue metallic Jetta Sportwagen TDI, 2002 Blue Eurovan Weekender BHW TDI
Hey [486], this is some awesome info. I've been able to piece together most of this myself reading on the UK/euro transporter forums. I've gotten a 6 speed 0a5 from a 140/180bhp T5 transporter van with the hopes of swapping it into my T4 eurovan. I've currently got a BHW mated to an 02d 5 speed syncro box, but it's geared too low for the type of traveling we want to use it for.

I've got a flywheel, and I had initially ordered a stage 2 endurance clutch kit from South Bend. Obviously the clutch disc didn't mate up to the 0a5 output shaft. I don't remember the size/tooth count off hand, but I had to order a clutch disc from Darkside Developments (love those guys and RyanP has set up a killer website and business, his shipping costs are also super reasonable.) Bolting everything up I noticed that the T5 clutch disc was thicker than the one that was initially made for the 02m set I bought from Southbend. For many reasons I ended up using the 02d just to get the van running at the time, but this winter I'm going to properly fit up the 0a5 gearbox. It's got the 4motion transfer case as well, so I'm excited to adapt the 4motion rear end as well eventually and use a standalone controller. I was tinkering around and found out that the T4 eurovan axles are splined the same and actually fit into the 0a5 inner CV joints. That makes fitting an older axle to the newer stub axles plug and play in a sense. It will also make fitting the axles way easier as I think I'll just have to cut down the T4 axles 15-20mm each side so they'll fit properly in the van/control arms. I'm still not sure completely about that though.

I have a few questions for you regarding the clutch discs. Do you know which Chevy/GM discs will fit? Are they from a specific model? Will any of the 9-9.25" 26 spline discs fit on an 0a5/6 output shaft? Any thoughts on running a clutch disc that is thicker than what the PP is designed for? My concern would be that it wouldn't release appropriately when the clutch was depressed. Is that unfounded?

Also, do the Tiguan's use the stub axle CV joints to connect to the gearbox? It appears the pictures of the 0a6 you have posted have stub axles that the CVs attach to vs. the cup and 6 bolt flange I'm used to on the 02j/m. Do you happen to know the size and spline count of the stub shafts? That would make sourcing inner joints soooooo much easier than trying to find/order from Ebay Romania like last time.

Edit: Nevermind, after digging around the T5 stubs are 26 spline for manual, 42 for auto. The Tiguan appears to be 40, so wouldn't fit either stubs. Still curious about the clutch discs though!

Thanks! -Ryan
 
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[486]

Top Post Dawg
Joined
Mar 1, 2014
Location
MN
TDI
02 golf ALH
I have a few questions for you regarding the clutch discs. Do you know which Chevy/GM discs will fit? Are they from a specific model? Will any of the 9-9.25" 26 spline discs fit on an 0a5/6 output shaft? Any thoughts on running a clutch disc that is thicker than what the PP is designed for? My concern would be that it wouldn't release appropriately when the clutch was depressed. Is that unfounded?
any of them that are 26 spline and 1 1/8 or 1 5/32 diameter, I do not know why they seem to call it two different names, the input shaft itself measures out to 1 1/8", the discs I've had in mine the last few thousand miles are listed in the catalog as 1 5/32 but they sure fit nice and perfect on the 1 1/8" shaft

It will likely release fine if there's clearance in there, you might run out of clearance or release bearing travel though
one option is to take the flywheel (if single mass) to an automotive machine shop and have them make the step a little bit deeper. On a DMF they are far too thin to cut down like that, so I'd get some high quality ground and hardened washers to space the pressure plate off the flywheel by the same amount as the thickness difference.

Also, do the Tiguan's use the stub axle CV joints to connect to the gearbox? It appears the pictures of the 0a6 you have posted have stub axles that the CVs attach to vs. the cup and 6 bolt flange I'm used to on the 02j/m. Do you happen to know the size and spline count of the stub shafts? That would make sourcing inner joints soooooo much easier than trying to find/order from Ebay Romania like last time.
They do indeed have little male splined stubs on either side.
I'm using the left front inner joint from tiguan/t5, the 6 ball style rather than the tripod style.
The rf inner is tripod style, same female spline but not as strong inside, the shaft necks down quite far. This shaft is actually available in the USA as auto/4motion tiguans still use it, where the LF inner is a male 26spl on the (tripod style) joint.
I ran one of these joints for a while when I had it set up as 2wd with welded together axleshafts that I broke rather spectacularly, all the internals are the same as the generic automatic trans tripod joints I describe below, they swap around happily and there are actually a lot of different length axles available but good luck finding the one you'd need. I've got three different length ones here in a bucket somewhere just from junk I've dragged home.
Edit: Nevermind, after digging around the T5 stubs are 26 spline for manual, 42 for auto. The Tiguan appears to be 40, so wouldn't fit either stubs. Still curious about the clutch discs though!
The 26 spline is the end that goes into the gearbox itself on automatics, iirc. They've got a real coarse spline, male stub on the axleshaft that is common amongst a huge number of models that use the tripod style inner joints.
The 42 spline I believe is an internal gearbox spline, the auto axles go into cups that fit in the side gears of the differential or something like that, I've never had one apart past swapping an axle shaft.
The 40 spl is common among both sides of the tiguan/t5 manual trans with mq500, this spline also shows up on the right front inner of automatic and DSG 4motion tiguans.
 

TurboStew

New member
Joined
Dec 30, 2018
Location
Ft Collins, CO
TDI
Busa Buggy
0A6 Stub Flanges

Is there a bolt up flange stub that can work in a Tiguan FWD transmission? I assume that the 02M/Q stubs won't swap. I am using this in a buggy project and I need as narrow flange to flange distance as possible. The 0A6 existing male stub with cv flange added puts me too wide. I like the 02M flanges cause they bolt right up to Porche 930 CVs. Even if a tripod direct plugin (with out the male stub) is available I can weld flanges to those. What is the internal stub spline size, the one inside the diff?

Ideas?
Anything that might work with a few Lathe/Milling ops?
 
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[486]

Top Post Dawg
Joined
Mar 1, 2014
Location
MN
TDI
02 golf ALH
sorry, no idea on the 02m parts, but so far pretty much everything points to 'no'
you can give it a go, but it is unlikely as all heck as just about nothing splined and VW fits anywhere that it wasn't intended
 

[486]

Top Post Dawg
Joined
Mar 1, 2014
Location
MN
TDI
02 golf ALH
I was thinking about it a bit back and I'd bet they're using something that looks like a passat 240mm clutch flywheel

The starter is certainly far enough out from the crank centerline. Try and find a passat FW. IIRC Whitbread made some single mass ones long ago.

ETA: I may well go this route in the future. A grabby clutch is not much fun constantly worrying about snapping axleshafts. My center shaft in the transfer case has to be hating life right now with 4340 axles to either side of it.
 

[486]

Top Post Dawg
Joined
Mar 1, 2014
Location
MN
TDI
02 golf ALH
bringing this back up from the dead
Anyone know what's up with the synchros on these? iirc there were some TT-RS guys having endless trouble with 1 and 2 synchos shearing tabs off when abused. Can't find any mention of it any more other than the thread on the vortex from 2014

I just got my junk back together (had stripped the splines outta the clutch hubs, so had to make some of a better design outta 4140 and got them heat treated) 200 miles later and the front of the car has to come off again as it isn't going in first any more. Feels almost like a stuck detent, but it'll go in all other gears including 2nd which is the same gate and everything. Pretty sure it is this synchro issue.
 
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