There is valuable stuff in here. If you have an interest in this subject 
matter, grit your teeth through the machine translation and read on.

The author is jenssyncro16 who does not appear to speak English that I can 
tell but he is obviously highly advanced in observations and thinking on 
this topic.

Fundamental to the manual gearbox of the Volkswagen bus T3 with special 
consideration of foreign engines in the T3 Here I would like to give times 
something to the gearbox of the T3 of me, whereby I would like myself to 
limit to the gearboxes for water-cooled engines The versions are made not 
for machine-builders and do not come also from such. Possible 
carelessnesses in the mode of expression one may forgive me thus. If 
however wrong circumstances emerge here, I ask urgently for adjustment! 
Design: 4 or 5-Gang 2-Wellen-Wechselgetriebe with integrated final drive. 
Types: I would divide the T3 gearboxes into three groups (independently of 
the engine): - 4-Gang-Getriebe - 5-Gang-Getriebe - syncro gearboxes Body: 
By the integrated final drive the gearbox has in principle three different 
sections: 1. Clutch housing, sometimes also clutch bell called this part of 
the gearbox is identically and freely exchangeable with 4 -, 5-Gang and 
syncro gearbox (nearly). With syncro little things are differently, 
nevertheless fit all bells alternately on all gearboxes. This the engine 
turned part contains the engine flywheel with clutch plate and friction 
disk, as well as the disengaging mechanism. In addition outside still the 
starter button at the clutch bell, which is positioned by means of 
solenoids on the large gear rim of the engine flywheel the clutch housing 
is logical-proves to the engine " openly, sits " and does not run in the 
oil bath. If one puts such a dismounted gearbox before itself, one sees 
also only the long getriebeeingangswelle, which in the installed condition 
into (hollow) the crankshaft of the engine rises up, and which clutch 
disengaging mechanism with clutch release sleeve (or also without 
bearings). The clutch bell is screwed with 10 (?) screws onto the other 
gear-box. Since behind it the oil-immersed part begins, one should remove 
these only after discharging the transmission oil. If only the bell is to 
be exchanged, one can place the gearbox also simply vertically and exchange 
the bell, then the oil can in it-remain. There are three different clutch 
bells for the T3 gearbox: - suitably for Volkswagen Wasserboxer (and 
Luftboxer) - for VW Reihen-4-Zylinder Diesel, also for Reihen-4-Zylinder 
Benziner - suitably for VW/Audi-5-Zylinder-Benziner, also for 
Reihen-5-Zylinder Diesel the latter bell is sold by VW exclusively in South 
Africa! To the operation of other engines (Ford, BMW, etc..) expanders are 
necessary. 2. Final drive Behind the clutch bell is the case of the final 
drive with the differential. It concerns here a winkeltrieb, whereby the 
small pinion (there are pinions with 6 and 7 teeth, which are not by any 
means exchangeable however also with same number of teeth) at the gearbox 
output wave sits firmly. The differential sits as it were crosswise in the 
gear-box and contains the large pinion and the actual differential basket 
with differential gear. With syncro there are special differentials with 
100%-Sperrklauen. With the 2WD sometimes so-called closing differentials 
(max. 30% locking action over friction) were installed. At this 
gehaeuseteil are then logical-prove also the flanges, where the drive 
shafts are bolted on. The getriebeeingangswelle is divided in this case, so 
that one releases here these and the front part, which reaches up to the 
engine crankshaft, exchange could. The front parts of the entrance shaft 
differ in the case of Diesel and fuel he gearboxes according to the length 
of the front pin, which runs at the pilot bearing. There are very many 
serial transmissions, which were always adapted to the respective engine 
and the targeted application by VW. Suction Diesels (in the 2WD) have the 
shortest, ever built transmission, some WBX (e.g. 60 HP WBX!!! and 112 HP 
WBX) the longest. The longest oh transmission supplyable of VW is 32:7 (= 
4.571). Oh transmissions are exchangeable within the 4-Gang -, 5-Gang and 
syncro gearboxes freely, however not between the groups! A final drive of 
syncro does not fit in a 5-Gang-Getriebe etc.. Different oh transmissions 
of the 5-Gang-Getrieben are however freely exchangeable. This is connected 
with the fact that the small pinion is firmly connected with the output 
wave and the shafts are at the 3 groups differently. The renewing of a 
final drive unfortunately causes the complete dismantling of the gearbox. 
3. Change speed gear After the final drive begins the actual change speed 
gear, which is vollsyncronisiert in the case of all T3 gearboxes. The 
design in principle is alike with all gearboxes. On the shafts are 
so-called fixed gears and lot gears. All gears are constant in the 
interference. During the gearshift selection a connection of the respective 
lot gear with the shaft is only manufactured. The fixed gears of 1. and 2. 
Gear are actually no gears, but they form a unit with the 
getriebeeingangswelle (at least with syncro and 4-Gang). By some 
characteristics of the individual building groups, the gears 1 and 2 are 
exchangeable and/or with the 5-Gang-Getriebe the gears 1 to 3 only within 
the series. Both the 5-Gang and the syncro gearbox are derived from the 
4-Gang-Getriebe! Thus the gears 4 and 5 of the 5-Gang-Getriebe correspond 
constructionally 3. and 4. Gear of the syncro and 4-Gang-Getriebe. By this 
circumstance the gear mating of the gears 3 and 4 (and/or 4 and 5) is 
freely exchangeable between all three gear construction rows! For the last 
gear (thus 4. or 5., depending on series) VW manufactured four 
transmissions: 41:48 (= 0.854) were built built in 4-Gang and syncro 
gearboxes for WBX 40:49 (= 0.816) exclusively into 5-Gang-Getrieben block 
39:50 (= 0.780) in 4-Gang and syncro gearboxes for Diesels, very rare (at 
least as production item) also times in 5-Gang-Getrieben to find? (0,76) 
this transmission gave it with 4-Gang-Dieselgetrieben, it is however no 
longer supplyable! 4. What happens with use of foreign engines? The basic 
construction of the T3 gearbox decreases/goes back actually already to the 
all first beetle gearbox of 1936! Thus this gearbox drags many 
constructional lack until today with itself, which cannot be repaired 
unfortunately also. The strongest ever built serienmotor was the 2,1l WBX 
with 82 kW/112 HP, engine identification letter DJ. this engine brings it 
on a maximum torque of 176 nm. The serial T3 gearbox is 
expenditure-provoked with this torque to to its power limit! Each further 
increase of the max. Torque (those max. Engine performance is here less 
importantly) durability will shorten. In the case of very strong foreign 
engines durability knows even only few minutes amounts to the following 
components to suffer with high torques frequently rash death: - the double 
taper roller bearing of the gearbox output wave - the gears of 4. (and/or 
5.) Gear. With GET down copies of the TDI engines with torques to 280 nm 
can the 4. (5.) gear after few kilometers tooth failure have - the gears of 
the final drive - the needle bearing cages of the lot gears (happens rather 
at high numbers of revolutions, thus rather with strong petrol engines) 
There are still many further problem places, that here is however in 
accordance with my modest opinion the most important. Remedy by Volkswagen 
production items: With VW OF South Africa becomes serial a 5-cylinder 
engine with 136 HP and a max. Torque of 200 nm in the T3 blocks. Since with 
beginning of this series the German gearboxes died rashly, some small 
modifications one accomplished. The most important change was the 
installation of two oil returning plates, which in the operation for an 
additional oiling of the final drive with double taper roller bearing and 
5. Gear ensure. These oil returning plates can be re-tooled with each 
German gearbox! In addition became the needle bearing for the lot gear of 
5. Gear and 1. Gear changed. Indeed the old bearing to Bj. was again 
introduced 1984. Apparent the plastic cage of the old bearing is more 
resistant to high temperatures. Furthermore oil oil grooves were 
temporarily trained in the gearbox output shaft, in order the needle 
bearings of the lot gears better to lubricate and also more oils to the 
double taper roller bearing bring. However current gearboxes from South 
Africa are not to already have these oil oil grooves no more, them seem 
thus not to have worked satisfactorily. So completely exactly I do not know 
it however. With these modifications the current South Africa gearbox holds 
the torque from the 5-cylinder engine (200 nm). Further increases are 
wohl.aber no longer possible, since VW does not offer stronger engines to 
OF SA. Remedy by Custom parts: Some offerers developed special gears, which 
are to tolerate high torques. Unfortunately these gear sets do not release 
the other problem areas, so that also with installation of high-strength 
gears no safety is given concerning the durability. Thereby however the 
tooth failure is nevertheless prevented Unfortunately there are no secured 
realizations, what bears the T3 gearbox maximum. It seems safe to be only 
that with use of engines with max. Torques over 200 nm will suffer the 
durability. The gearbox will hold, probably none is able to predict, it 
depends too much of individual efficient operation. Who constantly uses the 
performance of a strong foreign engine fully, must count evenly on 
premature Exitus of the gearbox. Characteristics of the TDI engines: TDI 
engines (particularly however the 4-Zylinder-Baureihe) load the gearbox 
particularly strongly. By torsional vibrations and by the brachiale torque 
with very low engine speeds (AFN engine: 235 nm with 1900 rpm) are very 
highly stressed all components. Here the use of high-strength gears is 
worthwhile itself particularly. Also the use of the two-frame flywheel is 
recommended. This ZMS smoothes the occurring torque points (to 600 nm are 
possible) when engaging the clutch and winding the engine up. 
Characteristics in the case of strong fuel foreign engines: Since petrol 
engines have mostly a high rated speed (up to 6500 rpm), other loads occur 
at the T3 gearbox. Here then frequently overheating damage is to be clamped 
after longer trips with high speed. Thus e.g. the plastic bearing cages of 
the lot gears melt. In addition the hardness layer of the gears is 
destroyed with transmission oil temperatures over 120 �C. Thus pitting 
effect and tooth failure occur. Adjustment of the transmission at foreign 
engines with production items: Nomalerweise are adapted gearboxes by the oh 
transmission. Heavy vehicles with winding up or very weak engines obtain 
short oh transmissions. Depending upon rated speed of the engine and the 
relationship of the driving resistance of the vehicle which can be expected 
to the performance of the engine the suitable oh transmission must be 
selected. A 1,9l TDI with 81 kW/235 nm takes therefore a longer 
transmission than a 1,6l TD with 51 kw/138 nm. The total transmission 
consists of the rolling circumference of the tires, the oh transmission and 
the respective drill step transmission. The number of conceivable 
combinations is nearly endless, for the operation from TDI engines is 
however only " is enough " for transmissions of interest. The longest, ever 
series gearbox for 2WD, blocked in German T3, has the oh transmission 32:7 
and the 5. Gear 40:49. Unfortunately this is only for alpine inhabitants of 
interest (mountain transmission). Since modifications are meaningful for 
the improvement of the durability anyway, one could on the 5. Gear 39:50 
reequip. A gearbox in such a way reequipped (built as said, never in 
series) hands then for the operation of a 66 KW TDI. it then there is still 
a little short, can one by tires with larger rolling circumference (e.g. 
205R14) help here. With the AFN-TDI (81 KW) one must still to be broken in 
be able. I attached individual example transmissions times as chart and 
diagram. (only in the final version) 5. Adjustment of the transmission at 
foreign engines with Custom parts: Two ways are possible also here! 1. 
other ganguebersetzungen: At the related accessory market the up to now 
following ganguebersetzungen exist: 5.Gang 39:50 (= 0.780) in strengthened 
version. Here series gears are improved by glass bead jets in their surface 
finish. These gears are sufficient for the 66 KW TDI, the border might with 
the 81kW TDI lie. 5. Gear 33:23 (= 0.697) these gears are up to 300 nm to 
tolerate. 4. Gear (and/or 3. Gear with 4-Gang-und syncro gearboxes) 28:29 
(= 1.035) as addition of the above 5.Gang with same characteristics 
Unfortunately has the employment of " is enough " for gear mating for the 
5. Gear (thus e.g. o.b. For transmission 0.697) with simultaneous rel. oh 
transmissions (thus e.g. 32:7) are enough the disadvantage that the jumps 
between the drill steps become very large. So it can be e.g. that one 
settles and in the next higher gear with under 2000 rpm lands the switching 
point with 4200 rpm. That can be done in the level still well, with use of 
trailer or at the mountain cannot one however no more up shift! Therefore 
also the offer " suitable " 4. Gear. I personally feel the jumps then still 
too largely, but there one can argue (see also diagrams) 2. other oh 
transmission at present the following oh transmission for 5-Gang-Getriebe 
is offered: 29:7 (= 4.143) With installation of this oh transmission can 
still the 5. Gear completely as desired between the three transmissions 
supplyable of VW to be selected. Optimal adjustment to various foreign 
engines is hereby possible. Also the AFN engine would be hereby very well 
mobile (see also diagrams) A combination with that completely are enough 
Custom transmissions 5. Gear is not meaningful, that becomes much too long. 
So people, that times as the further addition of the problems, which one 
in-acts in such a way with installation of a foreign engine I can show the 
diagrams only with the final version, since I provided her on Excel and I 
cannot convert it in HTML. Ask for numerous criticism Greetings Jens.

_______________________________________________
Derek Drew                                            New York, NY
CEO & Co-Founder
http://www.ConsumerSearch.com/
===========================
"Best Expert Review Site"
for product reviews on the Internet
Jan. 2001, PC World Magazine
==========================
80 South Street, 2nd Floor
New York, NY 10038
derekdrew@rcn.com
212-580-6486

Alternate numbers for the industrious phone caller that wants to try every 
avenue: 917-848-6425 (cell); 202-966-7907 (Work), 212-580-4459 (Home), 
202-966-0938 (Home), 978-359-8533 (fax [efax]), 212-269-3188 (Seaport 
office), 212-269-3188 (Seaport main number).