911 Transmission Rebuild Fundamentals

Step 1) Remove the transmission from the car

Step 2) Take it apart, making sure you keep track of all the pieces

Step 3) Examine the gears and dog teeth on each gear.
 

Here's an example of a really unhappy set of dog teeth and the matching synchros.

The teeth are completely gone, and the synchro is nice and shiny.  Not good.  This is first gear.

And now for second gear.  HMO.  Also not good.
 

After many expensive tools, throwing of hammered and some swearing, and, as you can see from the gear, a little blood letting as well, the new dog teeth  nod synchro are installed on first gear.


Looks like these teeth are frum Wes-Verginny!  Note the texture on eh synchro...

Second gear got the same treatment.  Here's the new dog and synchro.
 
 
 

Third gear as well...this guy must not have used the clutch much!
 
 

Here's first gear on the shaft.
reassembled input shaft

Yeah, I know, the workbench is a mess.  Hey this ain't no hi-priced photo shoot fer Vic-Torias Seecret!


 
 

And the output shaft as well (See background)   Case is nice and clean and spacing shims in place.

Now we install the shafts (always a treat) with the shifter rods.

Viola.

We use Dow Corning 731 on all the transmissions and engines.  At $95 a tube it's a bit pricey but it's well worth it.
Here we have installed the main gear section.  Not the shifter rod is installed.  No fun if you forget that.

Now simply pop on 5th and Reverse,

Replace the seals, etc. and put on the tail housing....
 
 
 
 

Step back a minute:  THis is a 1972 case, magnesium center and main housing.  If yo look carefully you
can see a couple of cracks where the detents are installed.  Someone over tightened these.  best hope is some epoxy.
 

THis is a shot of the main case on an early (Magnesium) trans.  Note the funky bearings that carry the selector
shaft.  They are made up of a four-row ball bearing set in a cage.

Again with the magnesium case

Lastly, we replaced the clutch guide tube and input seal.  The mag trans doesn't clean up very well, but it doesn't have to be pretty.