Replacing Speedo Gears on a T-5 Manual Transmission

 

Yes, replacing the speedometer drive gear in a T-5 tranny is much harder than its counterpart, the 700R-4, but its still something that can be done in the driveway by average DIYers, w/ common handtools.

The first step is to remove the center console. Then remove the rubber shifter boot bolted to the transmission tunnel.  With the transmission in Nuetral (and parking brake on), remove the four bolts holding the shifter to the tranny.

WithWith the shifter removed, you will now need to remove the roll pin in the "offset shift lever".   You will need to tap the roll pin straight down enough for the shift shaft to move freely.  Don't try to remove it, just make sure it moves independantly of the shift shaft.

Now raise and support the vehicle.  Release the parking brake (the wheels need to be able to turn).  Remove the driveshaft, be very careful of the U-joint endcaps, then can easily fall off and the needle bearings may fall out.

Remove the top bolt of the Torque Arm mount and remove the outer half of the mount.  This will allow you to move the Torque Arm towards the drivers side and up against the body. 

With a jack under the tranny, remove the crossmember bolts starting w/ the tranny mount nut (1) then the four bolts (2-5).  Once this is done, you can lower the tranny and let it hang (the engine mounts will support it).  Now is also a great time to replace your mount if it is shot or upgrade.  There are only two bolts holding it on at this point.

You may need to remove the remainder of the Torque Arm mount, and you may not.  This vehicle had a large vibration dampner on the end of it, so it had to come off.  There are two long bolts holding it on, one welded to the bracket, both w/ nuts on the other side.  The bracket is not removable untill the tranny is lowered away from the body.  Once you have the tranny lowered, you can remove the 8 bolts holding the extension housing to the case.  Make sure you have a large catch pan, you will loose about 3-4 quarts.

Once you remove the 8 bolts, you can break the seal loose by tapping on the end of the extenion housing.  Once you break the seal, let the fluid drain out.  Then reach on top of the housing and grap the offset shift lever (the item we tapped the roll pin out of earlier) and guide it off the shift shaft as you slide the extension housing off the output shaft/shift shaft.

Be very carefull once you remove the extension housing.  The offset shift lever has a spring loaded ball in it and you don't want to lose them or the roll pin that you tapped out.

You can now start to remove the plastic speedo drive gear.  Two words of caution.  The gear is fragile, and has been known to shatter if handled to roughly, and the gear is retained by a metal clip.  You will need to push down on the retaining tap while you gently tap the gear off.  I use a 30mm open ended wrench against the gear, then tap on the wrench to remove the gear.

Getting the new gear on can be a challenge.  Removing the gear, you found out how tight of a fit it is.  You will have to tap the new gear on also.  You will also have to be very carefull in lining up the gear w/ the clip.  If it isn't lined up, you will have to remove the gear and try again.  Place the clip in the hole and tap on gear over the clip.  Make sure it locks in on teh gear (like it was when you removed it).  The driven gear (located on the VSS sender or cable housing) can easily be accessed now, and should now be swapped out if needed.

Now that you are ready for re-assembly, make absolutely sure the bearing and plastic funnel are still on the 5th gear (overdrive) assembly.  These are very important if not in place, and can easily have fallen off during dissasembly.

With that said, you can now put the extension housing back on.  If you noticed that there was no gasket or O-ring, you are correct.  You should use the reccomended sealant, wich is Anerobic Sealer.  Use it just like RTV and spread it evenly over the mating surface.  Once you slide the extension housing over the shafts, you will need to reach back on top of the housing and guide the offset shift lever back on the shift shaft. This is tricky because you need to make sure the spring and ball are installed into the offset shift lever and that they didn't fall out.  You may need to crawl up inside the car halfway through installation to make sure its going together properly. Install the 8 housing bolts.

Reinstall the remaining removed components (Torque Arm mount, crossmember, Torque Arm and driveshaft).  Once you get under the car all back together, remove the fill plug on the side of the tranny (there are two plugs, the lower being the drain, and the upper being the fill).  My secret to filling this back up easily, it to pour the fluid into the top of the extension housing since the shift lever is out.  It has a drainback hole, and you can't overfill because once it gets to the proper level, the remaining will flow out the fill hole.  Then reistall the fill plug.

You will need to align the hole in the shift shaft w/ the hole in the offset shift lever so the rollpin can be re-installed.  Tap in the rollpin and reintall the shift lever and shifter boot, along w/ the center console.

Make a quick double check that everything is tight and there are no extra parts, and enjoy!