Problem: I heard some noises just before I was pulling out of an intersection and the truck popped out of gear and made some loud noises. She's dead Jim!

Symptoms: Transmission will not engage any gears. There are loud grinding sounds in park, drive, reverse or neutral. Transmission fluid spilling out from the front of the transmission. (This is spilling from the torque converter which has disconnected and fallen inside the housing)

Reason: I was towing a large 26 foot center console boat on a trailer 400 miles round trip to the coast for the duration of the summer. This overloaded pressure on the flex-plate caused it to fail and literally explode. (Pictures 1 & 2 & 3)

Diagnosis: Remove the inspection plate at the front of the transmission located on the bottom of the bell-housing. It is round and has 3 screws. This will determine if you have busted parts inside that area. (mine had the large chunk of metal pictured)

The Fix: (grab some coffee)

To start, this job is a two person job. And not your daughter or wife, this stuff is heavy and cumbersome to lift and maneuver around.

All bolts are metric! This is a British truck so put the American/Standard wrenches away.
BAG AND LABEL ALL BOLTS!!

First step: is to remove the cross-member bars bolted to the frame. Then take down the drive shafts, front and rear. (remember which end faces which on the front one)
Next: Take down the exhaust from the header flange all the way back. Unplug the oxygen sensors! and be careful doing it, they can pull apart. Leave them attached to the pipes as they may have rust holding them in. There are 4.
Then, go ahead and remove the transmission mount bolts, they will stay in place until lifted. Also remove the 2 transmission fluid cooling lines on the bottom and driver side of transmission. (17mm I believe) Also unplug everything you can find to unplug from the bottom before we go inside to the top. (All plugs only fit to one plug so don't be afraid and no need to label them all)

Now to the inside: The entire center console area will have to be removed. (Its Easy and takes about 20 minutes)
The shifter **** pulls right off. (Its tough, and be careful not to hit yourself when it does pop free) The gear position indicator at the base of the shifter works write out with a flat blade screwdriver or small pry tool.
The Transfer case shifter **** unscrews easily. The leather boots will pop out with a little effort.
Unscrew the window buttons panel and also pop the seat mover buttons loose as well. (These can stay connected or you can unplug and label them to make it easier)
There is a pin holding the parking brake cable to the parking brake handle. That must be removed as well to allow the console to lift up around the lever.
Once the console area is removed, also take out the heater ducts on each side and the padded area under the shifter area.
The shifter cable will need to be disconnected and pushed down through the floor. (There's a clip holding it in place)
This will expose the metal plate held by rivets. Drill those out, and you should see the top of the transmission area. (If you've gone this far, there's no turning back now)
Leave the transfer case shifter connected to it wires to avoid changing the adjustments of it. The Transmission shifter is easy to adjust and will most likely need it when finished anyways.

Lowering the unit: First loosen the motor mounts to allow some play when lowering the unit.
Set up a jacking system to handle the weight of both trans and transfer case.
Lift everything first to allow removal of the transmission mounts. Then slowly lower it a bit (watch from the top, #2 man, to see if anything is still attached. It won't lower too far, but it will lower enough for access to the 14 bolts that hold the bell-housing to the engine. (I used several short connecting extensions to make a long and bendable extension to maneuver to the bolts.)
Once loose, it may take some wiggling and a pry bar to break it loose to get the trans to move away from the motor. (be careful to keep everything aligned so that no damage is done to seals and gears.) The trans will back away and can be lowered down. (CONGRATS!!)

Repairing the damaged goods:
If the torque converter doesn't appear damaged, it may be re-used.
Unbolt the flex-plate from the fly-wheel on the engine and attach the new one. (Not hard to do at all)
Drain the torque converter and refill with 1qt of transmission fluid. DexIII fluid. Then re-installing it can be tricky. It must be wiggled and rotated in the process until 3 clunks happen. (Check You-Tube videos for demonstrations) Once it clunks the final time, the converter should be recessed in the bell-housing by an inch or 2. You will know when that final clunk happens. When in doubt, do it all over again.

The oil pan to the engine must also be removed to allow for re-installation and aligning the torque converter to the fly-wheel.

The re-installation process goes backwards from this point up.
Be sure to drain all fluids and re-fill accordingly. Tighten all bolts to spec using the rave manual for reference.

Finally, Ask any questions and try to do the job in a short time so that you don't forget any steps or parts.

GOOD LUCK!!

 

The flexplate can be cheked through both the inspection plate and the stater motor hole. To remove the trans/tbox, you take the parking brake housing off the back of the transfer box (4 bolts) then remove the shift cable from the transmission, then remove the HI/LOW cable from the body. You don't need to take anything apart inside. You also dont need to remove the oil pan, you simply remove the torque converter bolts through the hole that the starter is in. When reassembling, turn the torque converter through the inspection hole until the bolt holes line up. A new flexplate from rover is about 60 bucks.

 

How on earth would you access the top bellhousing bolts without taking apart the inside?
But then again, taking apart the inside was very easy and made the process much easier..

 

rotate the crank shaft

 

I've wondered this myself, but if I had to guess, one would remove the transmission and transfer case mounts, and lower everything slightly to gain access to the top bolts.

 

top bell housing bolts = remove the motor mounts and lower the front of the engine with a floor jack, plenty of room the reach them from the top

 

Nice write up.
I would quit towing boats with the Discovery.
Get an old diesel Dodge Ram or Ford or GMC for towing.

 

Just take the fan off and tilt the motor back to get to the top bolts off. If you are doing it without a lift you can just pull the plenum and coil pack out and get the bolts from the top.