091 Transmission Refresh
by Richard Atwell
Years ago Ron Van Ness wrote a fantastic article archived at the Type2.com website entitled '71 Transmission & Shift Rod Make Over. Much of the information including the contacts in the article is still valid but if you have a 76-79 bus with an 091 transmission the part numbers are different and there are some subtle differences.
This article aims to make clear what you'll need to perform a minor overhaul of the 091. Anything more than this requires that you take your transmission into an experienced repair shop for major work. You simply won't have any of the tools required to do the work even if you attempted to purchase the parts. See Ron's article for the tools you'll need.
This article is intended as a companion to Ron's article with it's descriptive images and explanations. However, all of the parts number for the 091 including the ones in common with the 002 are listed here so you don't have to go back and forth.
Click on images to enlarge.
Problem - You can get the shift rod into all gears but there is a clunk heard when you do it going into reverse or from 1/2 to 3/4 or vise versa.
Cause - Shift rod grommet missing.
The grommet rests in a hole in the frame and eventually the force of shifting cuts into the silicone rubber and it falls off into the cover pan and maybe through the hole and onto the road. Replacement can be done in situ. Simply undo the nut holding the coupler for the front and rear shift rod and slide the front shift rod backwards so it clears the hole in the frame. Take the new grommet and install it into the frame so that the outer groove is sitting on the frame and lubricate the rubber between the inside lips and then push the shift rod back into place and secure it.
There are no images of this part for the later style shift rod except in ETKA. Here's a scan of the fiche. It's part #15 not #19 which is a plastic piece for the earlier style shift rod.
This item is almost NLA. Reproductions are available but OEVeedub has several Genuine VW German parts at the time this article was written. The original is a thicker item and will last longer (probably survive lack of lubrication better).
Although the coupler and the components in the shift rod are the last to fail you might as well replace them if you've got the engine dropped or you're having shifting problems and you know the other components have been replaced. The bushings cannot be changed without removing the transmission to extract the rear shift rod.
There is a little confusion about the parts inside the shift rod. The part descriptions at Bus Boys are probably the biggest cause. Items L and M on that page are incorrect. They should read like so:
What happened is that part way through the 1977 model year VW added a third bushing to the rear shift rod to firm up the shifter. They didn't publish this information until late in 1977 and few people know about the modification. This article is a companion to the original with it's thorough descriptions and documentation.
The plastic bushings have been NLA for some time but poor reproductions are available. The front bushing is identified via metal ring that clips to the inside of the bushing. The rear bushing(s) are 1 piece plastic. You may as well replace any torn or decrepit shift rod boots that you see. Two are required.
All the reproduction bushings are poorly molded. You will have to remove the flashing left by the mold and possibly trim the nubs to get them to fit on the shift rod. Several folks have broken the frontmost rear shift rod bushing trying to install it. It seems the metal ring inside is too large and you should swap in the original ring before attempting to insert it into shift rod.
The shift coupler connects the shift rod to the input lever in the nose cone of the transmission. Several versions of this item exist:
I have no idea which is best to use. As usual the Mexican part is the worst looking of the bunch and the securing hardware isn't the same as the original. Although YMMV, you can probably expect it to fail before the first two. The HD unit comes with a hardware set that almost matches original (a washer is missing, the securing screw is not self locking and the split tube looks like it will require you to crimp it first). Urethane is almost always a good upgrade. And of course, the dealer item is pricey when you probably only need new guide pieces (823 711 477, 2 required).
|front shift rod bushing (74-79)||211 711 182||OEVeedub||$5.33||Genuine VW German|
|rear shift rod front bushing (68-79)||211 711 179||Bus Boys||$5.00||Aftermarket|
|rear shift rod rear bushing (68-79)||211 711 185B (2 required from
VIN 217 2053 839)
|rear shift rod boots (68-79)||211 711 183B (2 required)||OEVeedub||$10.24||Genuine VW German|
|rear shift rod coupler kit (68-79)||311 798 211||Bus Boys||Varies||by cost|
Problem - You are having trouble shifting into 3rd and 4th.
Cause - Chances are that you don't have a problem with the shift rod but instead the shift ball inside the nose cone has disintegrated.
The ball is made of plastic and over time whittles done into a tiny toe ring and falls out of it's socket while you are about to descend several thousand feet in elevation of course. The ball is all that connects the shifter lever to the input selectors that control the shifting forks.
Bentley has no photos of the 091 nose cone. Where is it? In the yellow Workshop manual naturally.
The first thing you'll notice that's different about the nose cone is that the bushings are different than the 002. Instead of the front bushing having a seal pressed into it, the seal is plain. Instead of a bushing that wears, there is a special bearing with balls somewhat like a needle bearing except it can slide as the shift lever moves. At the rear there is a similar bearing and you can easily remove them and press new ones in. This nose cone design will be less likely to wear the hockey stick compared to the 002 nose cone and you can see why an 091 nosecone upgrade is offered by the rebuilders for the 002 transmission. Both bearings should be lubed with MoS2 grease for long life.
You probably won't need to rebuilt the nose cone because of the improved design. I would suggest replacing the ball joint, gasket and shaft seal.
|Ball joint (68-79)||004 301 241A||Long Enterprises||$4||Plastic 241A, Metal 241As|
|Front shaft seal||001 301 227D||Different that 002 seal|
|Front and rear nosecone bushings||091 301 207||NLA||Special sliding bearing|
|Dust cover||211 711 115A||NLA|
|Shift lever "hockey stick" (68-79)||091 311 541||Bus Depot||$34.95||also try RC Trans|
|Nosecone gasket (73-79 from
VIN 213 2044 551)
|002 301 215A||Bus Depot||$1.67||also try Long Enterprises|
|Backup switch (68-79)||211 941 521||Bug Haus||$4.95||Hella Mexico|
I've never been able to find the 001 301 227D seal but recently I located a 013 301 227 seal for a Passat/Gol (Brazil models). The seal package says it's 15x24x7 which matches the dimensions of the Elring original:
I found this seal at Importec Parts. Their part number is J1162-52304.
The 091 bell housing is larger than the 002 to accommodate the 228mm clutch and matching flywheel. There is plenty if information in the Type2 archives and library with regard to transmission swaps.
Ron covered all of the details. Basically you want to replace the throwout bearing if you are changing the clutch or it's grinding on you. Lubing the guide sleeve depends on it's construction (see photo). I'm not sure if the plastic or metal sleeve came first but only the metal sleeve is available and it's probably more durable although I do not know what it does to the throwout bearing.
|Bell housing gasket||091 301 131||Bus Depot||$2.37|
|Throwout bearing (71-91)||113 141 165B||OEVeedub||$19.88||Sachs, OEM German|
|Drive shaft oil seal (68-79)||113 311 113A||BugHaus||$1.95||OEM German|
|Guide Sleeve (71-79)||113 141 181A||OEVeedub||$2.21||Denmark|
|Starter bushing 12v (68-79)||113 301 155||Bug Haus||$1|
|Release Shaft||091 141 701||Bus Depot||$9.95||Mexican (German is $64 @ Volks-Cafe)|
|Release Shaft washer||113 141 717A||Bus Depot||$1.40|
|Release Shaft bushing right||113 141 711A||Bus Depot||$5.25||Probably best left alone|
|Release Shaft rubber sleeve||113 141 721A (2 required)||Bus Depot||$1.49|
|Release Shaft bushing left||113 141 707C||Bus Depot||$10.18||Why so much!|
|Clutch Return Spring||091 141 723||Bus Boys||$2.85|
|Return Spring Guide Seat||091 141 727||Bus Depot||$2.85|
|Clutch lever circlip||N 012 420 1||Bus Depot||$1||2 maybe required|
Did your clutch cable break? Always replace the clevis pin when you replace the cable. Grease the cable before putting it into the guide tube and grease the lever end so it's less likely to corrode and snap. There are two boots that keep dust out. The first boot needs to go on after you thread the cable through the frame but before you insert it into the guide tube.
|Bowden tube boot (68-79)||211 721 365A (2 required)||OEVeedub||$1.88||Genuine VW Germany, aftermarket too stiff|
|Bowden Tube(68-79)||211 721 361D||OEVeedub||$5.95||Gemo, OEM German|
|Clutch Cable wing nut (68-79)||131 721 349||GoWesty!||$2.49||OEM German|
|Clutch Cable (73-79)||211 721 335J||GoWesty!||$7.95||Gemo, OEM German|
|Clutch Clevis Pin (72-79)||211 721 351A||GoWesty!||$3.49||Genuine VW German|
Got oil leaking from behind the CV joints on the transmission end?
|Drive flange grease cap (68-79)||002 517 289A (2 required)||Bus Depot||$3.49|
|Side gear oil seal||091 301 189 (2 required)||Bus Depot||$4.95|
|Flange o-ring (68-79)||002 301 185A (2 required)||Bus Depot||$1.99||I think Ron forgot about these|
|Side gear cover screws (68-79)||N 090 173 3 (4 required)||Bus Depot||$2.14|
There is a gasket set (091 398 005A) that contains these items:
I guess the Vanagon gasket is for packaging simplicity but why leave off the grease caps?
Before installing a new clutch disc and pressure plate you should check the endplay of the crankshaft and reset it. In addition you might need to get the flywheel resurfaced (this process requires that the same amount of material removed from the inner surface as the outer so the pressure plate holds the clutch in the correct position). The last preventative maintenance item concerns tapping the oil gallery plugs and putting in threaded inserts. It would be too bad if one popped after doing all the above work.
|1||Shim kit||021 105 280||Bus Boys||$18.50||Individual shims available at Bus Boys|
|2||Flywheel seal (72-79)||029 105 245B||Bus Depot||$9.95||Viton, Victor Reinz or Elring|
|3||Flywheel o-ring (72-79)||021 105 279||Bus Boys||$1|
|4||Pilot bearing (68-79)||111 105 313A||Bus Depot||$3.95||INA, OEM German (Some kits missing it)|
|5||Flywheel felt (72-79)||021 105 311||Bus Depot||$1||They send you 111 105 311|
|6||Flywheel washer (72-79)||021 105 275||Bus Depot||$1|
|7||Flywheel bolts (72-79)||N 014 335 1||VW Dealer||$4.95||The old bolts have stretched|
|Clutch kit (76-79)||029 198 141A||OEVeedub||$132.46||All items Sachs, OEM German|
|"Kingsbourne" clutch tool||5335||Bus Depot||$2.95||Made in Taiwan (Some kits missing it)|
When figuring out which shims you'll need, either calculate what you need or buy three of each shim in advance: you might need 3 of the same size shim. Because the endplay spec is 0.07-0.13mm it's too hard to predict what the factory set your endplay to and what shims you'll need to get it back to 0.09mm. Having said that, the 0.34mm, 0.36mm, and 0.38mm shims are most likely what you'll need.
|Shim||021 105 291||0.24mm|
|Shim||021 105 281||0.30mm|
|Shim||021 105 283||0.32mm|
|Shim||021 105 285||0.34mm|
|Shim||021 105 287||0.36mm|
|Shim||021 105 289||0.38mm|
Since the engine is out and we've come this far we might as well go all the way and seal all the SOB areas that are hard to get to. All of these items fit 72-79 models.
|Crankshaft seal (fan, rear main)||021 105 247A||Bus Depot||$4.95||Victor Reinz or Elring|
|Fan hub o-ring||021 119 125A||Bus Depot||$2.33|
|Oil cooler seals (required)||021 117 151A||Bus Boys||$1|
|Oil filter bracket gasket||021 115 359A||Bus Boys||$1|
|Oil filler tube gasket||071 115 315A||Bus Boys||$4.50|
|Engine Mounts (ruined by oil)||021 199 231C||Bug Haus||$13.95 pair||Meyle, OEM German|
|Engine Bay seal||411 813 225||Bus Depot||$19.95|
|Oil Pressure Switch (might as well)||021 919 081B||Bug Haus||$4.95||Hella German|
All part choices are my own personal choices and I've tried to locate the best quality without ordering from every vendor who was unable to answer my questions. You will save money if you purchase all of those items from a single vendor such as Bus Depot or RMMW but the part quality will vary according to the stock they have on hand at the time of your order. BTW, the RMMW online catalog used to be good but now it stinks. Get their printed catalog.
Why is the rear main seal called front main seal? Technically the flywheel end of the case is the front, but it's since it's called rear main on most other vehicles folks still use that term. You have to check the part numbers before you order to verify what you are getting sometimes. And yes, you 914 folks are just so lucky!
Rick Long tells me that for street use, the plastic shift ball lasts longer. The metal ball was created for drag racing.
11/27/03 - Created
05/09/04 - Added shift rod bushing warnings
05/15/04 - Confirmed nosecone part numbers and corrected description
06/09/04 - Added flywheel diagram
06/30/04 - Added more ball joint photos
09/06/11 - Fixed broken photos, added translate button, updated footer