Gearbox oil change

From VanagonWiki

Tools you'll need:

1. Jack and 2 stands
2. 4' 1/2 or 5/8 I.D. tubing
3. Funnel to fit tubing
4. 17mm Allen wrench (cut off to 1/2 inch or so on the short side) or Snap-on Wrench, 17mm hex X 21mm box, #S 5902 (see below)
5. 5 quarts transmission lube:

          Bentley says:
               Hypoid oil API/GL-4; MIL-L2105
               SAE 80W, SAE 80W/90
         The List says:
               Redline MT-90
      6.  Oil catching pan.
      7.  Small brush and some degreaser

Chock your front wheels. Jack up the right (passenger side) rear wheel and secure with a jack stand on the crossmember just inside the jack point.

Get your degreaser and brush and a couple of rags and crawl on under there from the rear. slide on past the engine till you're under the front exhaust pipe which runs from side to side. just above the center bracket and forward you'll find the drain plug. Clean off any dirt and grease with your brush and degreaser and wipe clean. Clean out the hex socket in the plug. DO NOT loosen it at this time.You want to be sure the FILL plug will come out before you do that or you will be up a tributary without any means of locomotion.

Move toward the front and find the place where the shift rod (it comes from the front of the bus where you shift) hooks up with the lever going into the transmission case. While you're there, inspect the rubber boot that covers that joint. {make mental note}. Look forward of that at the next rubber boot (or two boots if van is newer than June 87). Feel around just above for the same kind of plug as you just cleaned off.Clean this one too. Clean all around it so no crud will get in when you open it up. Again, clean the hex depression where you will insert your tool of choice.

Now get your plastic tubing, the Allen wrench or the snap-on tool, slide back under and loosen the plug you just cleaned. This is the fill hole. take out the fill plug and insert the tubing. Pass the rest of the tubing over the cross member and coolant tubes and out toward the wheel. There are a couple of ways to handle the "filler" end of the tubing, see the photos.

Get your drain pan and remove the drain plug. The old nasty will pour nicely into your pan.

Check out that plug!! It will have a load of metal filings attached to it. it has a magnet which has attracted all the pieces that flaked off every time you missed a shift. It's a good thing (not up in the oil wearing out your gears).

Take out the jack stand and return your van to level. Chock the rear wheels and jack up the front passenger's side, set a stand and do the same to the driver's side. You'll see more tranny fluid draining.

Let it drain for a couple of hours or overnite. When you see no more dripping you're ready to fill 'er up! Slide the drain pan under the fill hole. Lower the front of the van. Using your new lube oil, clean the drain plug. 

You should be able to reach the drain hole without jacking up the back again. Screw in the clean drain plug. Get it as tight as you can with your fingers.

Slide out and get your funnel. Stick it into the tubing and start filling. Pour in 4 quarts of the tranny fluid of your choice. Check for drips into the pan. If you see no dripping, break out quart number 5.

Fill your funnel and let it drain into the transmission case. Check for drips. Repeat until it starts dripping. Then, pull the tube and let the overflow drip out.

If you used the fossil oil (Bentley), jack up the rear driver's side one inch and let it overflow the fill hole. (Volkswagen now sez to only fill to 9/16" below the fill hole (to relieve hard shifting). List wisdom sez you can fill the case to the level of the fill plug (VW's original spec) if you used Redline MT-90 or other synthetic.)

When the drips have stopped, jack up the passenger rear again and set the stand. Slide on under and tighten the drain plug to 14 ft lbs (or 20 newton-meters if you prefer). Since you can't get a torque wrench in there it's kind of moot. Get it nice and snug and then a bit more. There are lots of threads sealing the plug. Do the same with the fill plug.

That's it. You are done and your tranny loves you again.  Vanagonaut 15:30, 15 August 2007 (EDT)

Alternate wrench, the Snap-on, 17mm hex X 21mm box, #S 5902. It's nice but the cut down hex (allen) key works just as well.