mustang ii      
T5 Transmission Swap     by Darryl Lang
These were pictures taken while performing a T-5 swap using a Mustang II bellhousing.  This was done in a '77 Mach 1 that already has an '88 5.0L motor and rebalanced Mustang II flywheel.  This engine had already broke 2 of the stock Mustang II RAD 4spd transmissions and needed this upgrade for some extra reliability.
The first comparisons I made showed the obvious difference in positions of the shifter and the transmission crossmember.  Before even doing this, I had to reduce the T-5 input shaft collar by 0.010" so it would fit into the Mustang II bellhousing.  After that, I found that the shifter was going to move about 1" towards the front of the car, and the crossmember was going to move about 3" towards the rear.
compare4.jpg (51114 bytes) compare5.jpg (51975 bytes)
The second major difference is the length of the input shaft for either transmission.  The T-5 is meant to go with a short bellhousing.  Putting the T-5 on a Mustang II bellhousing makes every thing fit about 1" further back.  I made some simple measurements and found I'd need the pilot bearing moved 1" further back.
t5input.jpg (46804 bytes) m2input.jpg (46008 bytes) t5bell.jpg (44024 bytes)
To move the pilot bearing, I had a local machine shop, Snohomish Iron Works, create a bearing sleeve.  I used the dimension of the factory 5.0L roller pilot bearing, and just had them make the  sleeve 1.5" long instead of the stock 0.5".  The dimensions are 1.5" long, 1.375" outside diameter, and 0.940" inside diameter.  The roller bearing was pressed out of the stock sleeve, then pressed into this new sleeve.
sleeve1.jpg (39776 bytes) sleeve2.jpg (44092 bytes)
Some pre-installation photos:  The transmission was degreased with mineral spirits and Castrol Super Clean, then washed down with lacquer thinner and painted with DupliColor dark blue engine paint to match the motor.
t52.jpg (48824 bytes) m2bell.jpg (46084 bytes) motorready.jpg (49480 bytes)
Engine installation was no different than normal, but I did have to take the y-pipe back off before it would fit back in.
goingin.jpg (51448 bytes)
Moving the transmission crossmember back wasn't too hard.  I used 3/8" X 6" grade 8 bolts to mount the crossmember behind it's stock location.  I found that 2.5" X 1/2" ID pre-cut pipe was perfect to keep the crossmember from crushing when tightened.  I also used the stock Mustang II transmission mount.  This all would have worked perfect, except the tailshaft ended up too close to the transmission tunnel on the passenger side.  I ended up slotting the crossmember sideways so I could move the tailshaft about 1/2" towards the driver's side.
cross1.jpg (50336 bytes) cross2.jpg (44772 bytes)
The most expensive part of this swap (not including the transmission), and biggest surprise, was that the driveshaft ended up too long.  I had the driveshaft shortened by exactly 1" and rebalanced  by another local shop, Drivelines NorthWest.
Inside, I had to remove about 1/2" of metal at the front of the shifter hole.  I also had to use the shifter boot from an '85 Turbo Cougar (Leather), and an automatic transmission bezel in the center console.  The center console had to be moved forward about 3/8".
inside.jpg (42816 bytes)

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