VW T25 T3 and Syncro Gearbox Drain Plugs; The Good, The Bad, and The Ugly
On the VW T3 T25 Syncro gearbox, the magnetic drain plug is located at the bottom of your bell housing in the centre. To undo this, you will need a 17mm Allen key these can be found at most motor factors.
Both the gearbox oil and the drain plug magnet are a very good way to determine the state of your gearbox and how much wear is evident. A fresh magnet will look like this and over time will attract whatever metal finings are present in the oil that has either worn or broken away from the internal components.
A VW T25 T3 or Syncro gearbox in good condition will generally look like the ones below showing very little material present and thus wear. The sludge present with be of a very fine nature and have no pieces of metal present.
A VW T25 T3 or Syncro gearbox with considerable wear will look quite spikey like the one below and generally needs a rebuild. Often there will be small finings or even very small lumps of metal present within the sludge. A drain plug exhibiting more material than this, I would advise stopping driving immediately. As there is significant damage to internal components and prolonged driving will generally lead to the destruction of your gearbox.
Drain plugs resembling the one below often have pieces of metal present evident from either broken bearings or gear teeth. These ones were from VW T25 T3 or Syncro gearboxes which had considerable damage to them, resulting in the replacement of major parts to make them serviceable again. If your drain plug looks like these, STOP DRIVING IMMEDIATELY. There is significant damage to internal components and prolonged driving will generally lead to the destruction of your gearbox.
Like all things, it is often cheaper and easier to fix a box that has less wear than it is to fix one which has had severe damage so the quicker you can get your gearbox looked at the better.
Hope this is of help,