Since I needed to split and measure up the innards of one of these for r+d purposes I thought Id take a few snaps as I went incase anyone is thinking about taking apart there's for whatever reason, they're pretty handy to split and if you've done it once shouldn't take longer than 30min or less. Its a good idea to wash off the heavy crud first, luckily, done so before I picked this one up First up, drain the oil, an old wheel stud and a 17mm spanner and away you go, Next, the drives have to come out, two M8 bolts threaded in against some nuts or spacers and out they pop, Turn it up and remove end cover, these bolts are 11mm so you may have to root around for that spanner..., Off, 5th gear exposed, With a scriber mark the selector rod where its bolted together at case, this hole is slotted for adjustment, Open, Out, Next, the fifth gear fork pivots, Off, Next the ring, un-clip spring and note how its fitted, its behind all three, Lift the ring up, Press all three back away from centre at this point, Lift off ring, Notice the three flat spots for when your refitting, And remove these, Next up, opening the bolts securing the end gears, I use a cloth between gears to lock them, it hasn't failed me yet, Drop the ring all the way down again to lock the full assembly together, that is, the gear onto shaft, and open bolt, Swap cloth and open the other bolt, Set-up your pullers and pull off gears, removing the ring above again to get the pullers closer to gear,
Off, And the same again, Out with the selector tower, Quick re-cap on parts removed, And the tower shaft support bush on the opposite side, Open all the bolts you see facing up holding case halves together, And turn it on its side and open the ones in the bell-housing, Incl the 4 nuts holding the internal bearing carrier, And turned up again open the torx bolt holding the reverse gear shaft support block, Out with the four fork pivots, two per side, And the other reverse gear shaft support block bolt, Another re-cap, Carefully break the sealer joining both cases, Lift off main case, The forks, these can be lifted away now too, it might seem a bit out of control at this point but its ok, they all go back just as easy, Out, Reverse gear fork has to come out, open the bolt and remove complete fork assembly, You can now lift out all three shafts, Out, And the diff can come out now too, Just lifts up, Bag the shafts and diff if your setting them aside for a while, If your fitting a new diff or changing bearings then the box will have to be checked and re-shimmed on assembly, this is to make sure the correct pre-load is applied to new parts or bearings on re-assembly. Shims go behind the bearing races and can be got off vw in a number of thickness's, the case is re-assembled with just the shafts and diff installed and the axial play and turning torque is checked and the sets are shimmed as necessary to meet the correct tolerances and torque. SPACER RINGS DIFFERENTIAL THICKNESS (mm) PART NUMBER 0,65 02A 409 210 0,70 02A 409 210 A 0,75 02A 409 210 B 0,80 02A 409 210 C 0,85 02A 409 210 D 0,90 02A 409 210 E 0,95 02A 409 210 F 1,00 02A 409 210 G 1,05 02A 409 210 H 1,10 02A 409 210 J 1,15 02A 409 210 K 1,20 02A 409 210 L 1,25 02A 409 210 M INPUT SHAFT THICKNESS (mm) PART NUMBER 0,650 02A 311 140 0,675 02A 311 140 A 0,700 02A 311 140 B 0,725 02A 311 140 C 0,750 02A 311 140 D 0,775 02A 311 140 E 0,800 02A 311 140 F 0,825 02A 311 140 G 0,850 02A 311 140 H 0,875 02A 311 140 J 0,900 02A 311 140 K 0,925 02A 311 140 L 0,950 02A 311 140 M 0,975 02A 311 140 N 1,000 02A 311 140 P 1,025 02A 311 140 Q 1,050 02A 311 140 R 1,075 02A 311 140 S 1,100 02A 311 140 T 1,125 02A 311 140 AA 1,150 02A 311 140 AB 1,175 02A 311 140 AC 1,200 02A 311 140 AD 1,225 02A 311 140 AE 1,250 02A 311 140 AF 1,275 02A 311 140 AG 1,300 02A 311 140 02A 311 140 1,325 02A 311 140 02A 311 140 A 1,350 02A 311 140 A 02A 311 140 A 1,375 02A 311 140 A 02A 311 140 B 1,400 02A 311 140 B 02A 311 140 B 1,425 02A 311 140 B 02A 311 140 C 1,450 02A 311 140 C 02A 311 140 C 1,475 02A 311 140 C 02A 311 140 D 1,500 02A 311 140 D 02A 311 140 D 1,525 02A 311 140 D 02A 311 140 E 1,550 02A 311 140 E 02A 311 140 E 1,575 02A 311 140 E 02A 311 140 F 1,600 02A 311 140 F 02A 311 140 F 1,625 02A 311 140 F 02A 311 140 G 1,650 02A 311 140 G 02A 311 140 G 1,675 02A 311 140 G 02A 311 140 H 1,700 02A 311 140 H 02A 311 140 H 1,725 02A 311 140 H 02A 311 140 J 1,750 02A 311 140 J 02A 311 140 J OUTPUT SHAFT THICKNESS (mm) PART NUMBER 0,65 020 311 391 P 0,70 020 311 391 Q 0,75 020 311 391 0,80 020 311 391 A 0,85 020 311 391 B 0,90 020 311 391 C 0,95 020 311 391 D 1,00 020 311 391 E 1,05 020 311 391 F 1,10 020 311 391 G 1,15 020 311 391 H 1,20 020 311 391 J 1,25 020 311 391 K 1,30 020 311 391 L 1,35 020 311 391 M 1,40 020 311 391 N Hope this helps, Brian.
Thanks for the wheel stud and spanner idea Brian. Was searching for the size of the hex bung and found this, very useful .
Bloody brilliant thread de-bunking the mystical nature of the gearbox. Dont get me wrong.......there are some specialised tools needed if you're going to play with gears and syncros but for say diff and 5th swapping this is ideal info.
Excellent write up. I have done a few, and the fifth gears are normally stuck hard onto the splines. A bit of heat has been needed to help the pullers. Likewise, the 1-4 gears onto the mainshafts. Also, isn't it surprising the oil is so dirty? Once you spend the time to strip and rebuild, and thoroughly jizer everything, the next time (!!) you strip it it will still be super clean. Jon
Shims only go behind the upper race, unlike the 020 the abf was machined right from the start so the lower one doesn't need one. Also the 5th gear selector doesn't need to be marked and unbolted, it goes through the hole fine without loosing it's position. Quick tip, remove the case bolts in the bell housing first, will save you having to tip the box over and get any remaining oil all over the place lol, I forget this every time....my workshop stinks lol Anothe tip for anyone who've stripped alot of 020's is, on the rebuild of the output shaft, remember that the 1st-2nd gear synchro hub that locates reverse goes the other way around. Easy mistake to make, and means a full stripdown if you get it wrong and don't realise.
Cheers for the picuture, handy for those not sure if it's a DIY job or not Quick Question to add on to this thread, I have done a couple boxes myself I've found couple times on this pic The smaller gear, and you can see this in the picture the 2 gears don't mess up 100% true - could even be 2+mm difference I've also seen couple OEM (in warrenty) boxes fail on this gear, stripping the teeth off, as well as on my own box running high torque any info on this, and how to get it right?
Unfourtuatly the 2 shafts are set with preloads, and not actually spaced into position. The input shaft has fixed spacing all the way through, as 1st and 2nd are machined on, and the 3rd, 4th and 5th spacing is fixed. The outputshaft is preloaded from the bottom so the shaft is set(unless you prebuild, and start machining the top bearing housing for the top taper roller, which isn't recommended as there's not enough meat there) The synchro hubs are then set into position with circlip retaininers, so there's no margin for spacing, until you come to the thrust washer on top of 4th. Unfourtuantly there is only 1 size available Part number 02a 311155A so it's not an adjusting shim.(same goes for the one under the 5th gear on the input shaft) From what I can see it's set 'as is'.
Great thread If i ever decided to start playing with gears i'll be hunting this again.. Sticky..??? Quick easy to answer question: Can i take my selector tower off without stripping.? I just want to get in to clean and spray.
sounds a silly question but refering to the sbove posts, if i want to take my tower out, how do i know its in neutral as mine has been out of the car a while. what doees the tower look like in neutral? any pics? thanks
Similar situation Ditchyboy. I bought mine off ebay. So din't have clue what was neutral.? But thinking about it i guess the middle position of the leaver would be neutral.? Mine was still wedged on solid whatever position so I read another post that said to give it a hit with a mallet at the bottom of the tower.. i tried that but ended up smashing the black cap.. Cant seem to find a part number on vagvat either.. Edit: Found Part No: 02A 945 413C
Neutral is when the input shaft rotates, but the diff doesn't. Sorry of that's stating the obvious. Again, very very useful guide Mart: Done that. Put 020 1st/2nd sync in upside down. Doh Jon
