5th Swap Page 2

To get the gear off, you need to remove the 12mm XZN or triple-square bolt from the center of the main shaft (this pic was taken later, after the bolt was loosened)....



In order to remove the 5th retaining bolt, you need to stop the main shaft from spinning around. To do this, select 2 gears at one time. This is why the selector shaft was removed, so we could select 2 gears. In the pics, I use 5th and reverse.

Here is a pic of the 5th synchronizer sliding collar, when 5th is not selected. You can see the small teeth of 5th gear under the ring, and if you look close, you can just make out the small teeth of the brass synchronizer ring in the shadow of the sliding collar. When you hear grinding, those are the teeth that grind. They are grinding against the inside of that sliding collar. They are easily damaged, so remember that grinding = bad ;)



Here is a pic showing the 5th gear selected, after I pushed the sliding collar down and engaged it with the small teeth on 5th gear. The trans is in 5th gear now...



If you look inside the selector hole now, you can see the fork furthest from the camera has moved towards the engine...



Reach in and push the fork closest to the hole towards the engine as well. This will engage reverse gear. You can select any of the forks to pick any 2 gears, but reverse is closest.


As Vdubs pointed out, it is possible for the trans to slip out of reverse on earlier trans models not using a reverse over-center spring inside, so you might want to use a flatblade screwdriver to reach in and move one of the other forks to one side or the other. :P

The first fork only moves towards the engine, and that's reverse gear, then the second fork moves back and forth for 1st/2nd, then the next fork works 3rd/4th, then the last fork is 5th as you've already seen.



Here is a pic again into the selector bore, showing now the closest fork moved towards the engine as well, so the trans is in both reverse and 5th gears, and is completely locked up now.
Now you can remove the big XZN hollow 5th retaining bolt. It is in there kind of tight, so have a cheater bar ready. It is installed at 111 ft-lbs, and it is old, and thread locked. ;)



Once the bolt is removed, you can remove the 5th gear from the main shaft. It will either wobble up fairly easily with finger force, or fight you and be seized on. Either way, you'll notice the shift fork is keeping you from fully removing the gear, so it needs to be removed. Ideally, you can lift the 5th gear, and the sync hub and collar and shift fork all off in one piece. Ideally ;)
To start, you need to unlock the 5th adjustment tube. It is locked with this bar which is pressed onto some splines preventing the splined/threaded tube from spinning. Use a screwdriver to pry the bent ends up a bit, then pry the bar up all the way, once the bar is up, turn it sideways so it won't fall back down again. If you don't have one of these, and have a tube peened in place, see the bottom of this page for more info...





Use either the VW special tool or some homemade version to engage the splined/threaded tube (the tube has 2 notches in it, and the tool has 2 tabs to engage them) and spin it CCW...



The shift fork will unscrew from the threaded tube, and allow the fork to be lifted free of the tube which will stay in the trans....



If things work out well, you should be able to wobble the gear and lift the entire assembly from the shaft....



If things didn't work out to well, then the hub is stuck onto the shaft. You will need to pull the gear, and to do so will probably require the removal of the shift fork to let the puller hooks in close enough to get under the gear.

Lift the sliding collar upwards after you have unthreaded the tube from the fork...



When you lift this collar up, the 3 locking sync keys will want to pop out of the hub...



After the sliding collar is lifted off the hub, if there are any locking keys remaining, go ahead and remove them....



Attach a puller to the gear and yank it off the main shaft...



OOK, now one way or the other, you've got the "driving" 5th gear removed, and now the "driven" 5th gear remains. Use a good set of circlip pliers, and remove the circlip....

For 16V and 2.0 trans (up to date code 01067), the circlip and washer are replaced by a locking clip. The driven gear also has a deep groove to allow the locking clip to lock into place. The pinion shaft groove only allows one style of clip, either the 8V circlip, or the 16V locking clip. This means your 16V or 2.0 code (prior to 01067) can only use deep grooved gears, but your 8V (or MK3 codes after 02067) can use deep or shallow groove gears. The bottom of the page has more pics to explain...



These snap-off pliers do a pretty decent job on all the circlips in the trans....



If the driven gear doesn't just wobble off with finger force, then use a puller placed as shown, in the 2 pockets in the case for the puller hooks...



Here is the trans minus 5th gear. You can see the 2 pockets for the puller hooks for the driven 5th gear on the right in this picture as well...



Assembly is pretty much the reverse of the removal....put the driven gear on with a new circlip, install the driving gear with a new retaining bolt, thread the shift fork back on and lock it with a new lock plate after adjusting 5th gear.
To adjust the 5th gear, turn the threaded tube to move the shift fork in and out. There should be 5mm space between the top of the fork and the top of the splined tube. I adjust it so the sliding collar can float on the shift fork when both in and out of 5th gear. You don't want the fork to be holding the collar in place and wearing when in or out of gear....



Use something at least 12mm thick like a wrench to support the shift fork (protect the trans gasket surface during this), and press the new locking plate down to lock the tube in place. The pic shows the VW tool but it just needs pressed down onto the splines and doesn't require the special tool...



Install a new 5th cover gasket and stick the cover back onto the trans. It might take a bit of tilting and moving to get the spring and rod into the hole and then the cover over top of the 5th gear, but it'll go.
Install the selector shaft into the housing, put the spring and cover back on, bolt in the reverse switch, put the detents back in and you should be done .

Here is why the 16V codes and MK3 codes up to June 1st, 1997 will only accept the 0.80 and 0.91 5th gear sets. Those gears are the ones that use a deep groove in the top face of the gear for the output shaft, which secures the special locking clip. The locking clip has a tab that fits into the groove to stop it from sliding off. If you get a gear and machine a groove into the face for the special clip to lock in, it'll work just fine.