No, you can't use the r+p set from a 4 speed in a 5 speed or the other way around for that matter. You also can't use either of those in a Syncro tranny or the other way around. Also you can't use the early aircooled and diesel 4 speed r+p sets in a waterboxer 4 speed or the other way around. Machining can be done to allow some mixing between 4 speed types, or so I was told.

The r+p set in Vanagon trannys uses a pinion shaft which runs the full length of the tranny. One side of each of the other gears fits onto machined locations on this shaft. A complete tranny rebuild is involved to change the r+p. Tranny rebuilders have access to various r+p ratios that were never used in North American models so it is likely that you can get the gearing combination you desire but not by simply mixing r+p sets from different tranny families.

Mark

Kim Springer wrote:

>Hi, > >For inquiring minds: > >http://www.t3-infos.de/images/T3-Getriebe.pdf > >I have the AAP transmission in my Tristar. Has anyone ever considered (or done) a conversion/hybrid with a diesel 5 speed gearbox and a 4 speed ring and pinion? > >Would this work to make a "freeway flyer" 5 speed? > >Kim Springer >'89 Tristar > >ps. glad to see the John Wallace, email generating, hacking, exchanges, die off! > > >