Modern Driveline brings your 1979-93 Mustang into the 21st Century with crispy T-56 Magnum smoothness and performance
When Ford added a five-speed to the Mustang’s transmission line-up in 1983, it seemed way out there for those of us old enough to remember when even four-speeds were a fresh mainstream idea from Detroit. In time, five-speeds became the norm that is until Detroit decided we needed one more speed to think about and shift into.
Enter the six-speed manual transmission as an enhancement to hot Fox-body 5.0L Mustang performance. Although the first factory six-speed first arrived in the 2000 Mustang Cobra R and 2003-04 Cobra, we were inclined to ask why a six-speed wasn’t possible in a Fox-body Mustang for those of us who like the nimble, sure-footed Fox. This was when our engineering department decided to investigate how to get six-speed performance into a 1979-93 Mustang. It wound up being easier than we ever imagined.
Modern Driveline introduces a complete bolt-in TREMEC T-56 Magnum XL performance conversion package for the 1979-93 Mustang.
What’s more, you can perform this conversion in a weekend and be back on the road Monday.
Five-speed shifting has been a Mustang staple since 1983. The TREMEC T5 has served us all very well in more than 20 years of continuous availability and service.
However, TREMEC’s T-56 Magnum six-speed will help you forget all about that T5 box when you discover the thrill of the T-56’s gearing, easy shifting, and the benefit of two overdrive ranges for the open road.
Get Into Overdrive x 2
The T-56 Magnum is a revolutionary new six-speed transmission that combines the rugged demeanor of the TREMEC TKO five-speed and OEM TR-6060 (Shelby GT-500, Corvette, and Viper) to create the smoothest shifting six-speed transmission in the industry. You get OEM durability and aftermarket toughest in a single six-speed box. We’re talking crisp shifts, no missed gears, beefiness, heavy-duty bearings and synchronizers, and greater torque capacity for your Fox 5.0L Mustang.
What makes the TREMEC T-56 Magnum from Modern Driveline a great investment? – Here’s the beef…
- Beef: The T-56 Magnum goes the original T-56 one better because it is a completely new TREMEC six-speed transmission with a redesigned heavy-duty main case with heavier webbing and more strategically placed material able to withstand 700 ft/lbs of torque. What’s more, the T-56 Magnum is engineered to prevent leaks and remain true to form even under the most demanding conditions.
- Gearing: Modern Driveline’s all-new T-56 Magnum has an incredible 700 ft/lb torque capacity with gears similar to those found in the TR-6060 used in the Shelby GT-500, Chevrolet Corvette, and Dodge Viper. These gears sport a great face width plus two-piece laser beam welded construction. Two-piece units allow for much greater control over tooth angles, pitch, alignment, and more. This eliminates the chance of an over-thrown shift.
- Countershaft: Radically bolstered one-piece countershaft, which resists distortion. What’s more, it sports larger bearings in critical support areas for greater stability than ever before.
- Input Shaft: New and improved input shaft provides significant strength as the T-56 Magnum’s first line of defense against failure. You get a thicker 26-spline shaft with longer splines to accommodate today’s twin-disc clutches not to mention more material throughout. TREMEC also gives you a larger input shaft bearing for greater support in front. Ford 10-spline shafts will not be available. Synchronizers: Because the Magnum has wider gears it also gets new high-tech synchronizers with cutting edge technology. These guys are considerably narrower than the old T-56 synchronizers featuring fine pitch tooth angles to effectively decrease the amount of travel necessary for proper engagement. Spring-loaded ball-type inserts reduce friction, which reduces shift effort.
- Shift Forks: You couldn’t imagine a redesigned T-56 without redesigned shift forks featuring shift keys to virtually eliminate the chance of bent shift forks. This keeps shift forks on course without any chance of deflection and failure.
- Retainers: When TREMEC completely redesigned the T-56 it took a close look at retainers and fasteners. Instead of the time-worn snap ring, TREMEC went to a new split ring retainer design that will handle greater thrust loads and allow for tighter tolerances.
- Main Case: Though the T-56 Magnum looks similar to the old T-56, it is not the same transmission case by any stretch of the imagination. There’s more beef in this case not to mention changes in the dimension that make it a far better case. It can handle greater loads than the original T-56.
Real Beef — And Lifetime Tech Support
Modern Driveline is well known in the industry for unlimited lifetime tech support, and that’s what you get when you do business here.
When you buy the MDL T-56 Magnum six-speed conversion package for your 1979-93 Mustang, here’s what you get:
- TREMEC T-56 Magnum Six-Speed Transmission
- QuickTime Bellhousing for 5.0L Engine with separator plate
- Clutch Fork & Release Bearing
- Superior Multi-Friction Kevlar/Organic Clutch & Pressure Plate
- Pilot Bearing
- Modern Driveline Steel Flywheel (28 or 50-ounce offset)
- All Hardware
- All Appropriate Wiring Harnesses
- Four Quarts of Synthetic Transmission Fluid
- Steel/Urethane Crossmember with Mount
- Clutch Alignment Tool
- Shift Knob
- Detailed Instructions
- Hydraulic Clutch with some applications
Shifter ball, boot, and handle are removed first.
Speedometer cable is disconnected next using a 7/16-inch socket or box end wrench.
H-pipe and catalytic converters are removed next. Original exhaust systems will have four cats. Most replacement systems will have two. O2 sensors and Thermactor Emissions tube must be disconnected.
Driveshaft is disconnected at aft axle flange as shown.
With transmission crossmember and mount removed and transmission properly supported, the transmission is disconnected at the bellhousing. We do this for easier access to the bellhousing to engine bolts and clutch cable.
With transmission safely supported by a hydraulic jack, removal comes from pulling the T5 aft and away from the bellhousing.
This is the factory T5 bellhousing with the clutch fork and cable still connected.
Two-bolt starter is removed next using a 9/16-inch box-end wrench.
A 5/8-inch deep well socket gets the bellhousing to engine bolts, which frees the bellhousing. Clutch cable is also disconnected at this time.
The superior clutch is removed at this time using a 13mm socket.
Because we have a healthy flywheel, we’re going to remove and resurface clutch contact surfaces for good adhesion.
Clutch pilot bearing looks good.
The factory aluminum separator plate is removed at this time and will be replaced with a ‘QuickTime’ steel plate compatible with the QuickTime bell and T-56 Magnum.
This is the time to replace the rear main seal if there is leakage.
QuickTime separator plate, also known as a block plate, is installed next.
Flywheel’s face can be resurfaced by a machine shop or quick scuffed like this with a fine abrasive wheel.
The flywheel is installed next using a good thread locker/sealer on new bolt threads.
Never reuse old bolts.
Remember, these bolts go directly into the crankcase, which means they will leak if you don’t seal the bolt threads.
Flywheel bolts are torqued in one-third values in a crisscross fashion to 75-85 ft/lbs.
Snug first, then torque in thirds.
Whether you’re installing a new clutch or reinstalling the existing clutch, pressure plate surfaces must be hospital clean using brake cleaner repeatedly until the rag is clean.
A fresh Superior multi-friction clutch disc is centered with an alignment tool, then, the pressure plate is installed with bolts torqued down slowly in one-third values using a thread locker on bolt threads.
Pressure plate bolts are torqued in one-third values to 23 ft/lbs in a crisscross fashion.
QuickTime bellhousing from Modern Driveline is SFE certified and easy to install using a 5/8-inch deep well socket.
Modern Driveline clutch kits come with a clutch alignment tool for your convenience.
However, for even more precise alignment, opt for an old transmission input shaft, which is even more accurate in terms of alignment.
The TREMEC T-56 Magnum carries the clutch fork as shown, which fits right into the QuickTime bellhousing. Installation is easy.
From the left-hand side, the clutch fork and bell relationship looks like this.
You can go with a cable or hydraulic clutch with an internal slave.
The TREMEC T-56 Magnum fits comfortably in the 1979-93 Fox body’s transmission tunnel.
Modern Driveline’s tubular T-56 Magnum crossmember slips easily into place as shown.
With input shaft splines into the Superior clutch disc, QuickTime bell bolt-up is easy.
Modern Driveline’s aluminum driveshaft from Dynatech is a perfect fit, with ¾-inch of slip yoke showing with the aft pinion flange connected and wheels on the ground.
Stock clutch cable installs as shown and is easy to adjust.
Any modifications to the transmission tunnel are minor in scope with some of the overlap cut out or hammered flush.
The T-56 Magnum’s backup light duplex plug is different than the 1979-93 Mustang’s female connector. You will have to go with the Magnum’s male duplex counterpart, which is available from Modern Driveline.
The 1979-93 Mustang’s mechanical speedometer drive splines in as shown without special modifications.
Like the speedometer driven gear, the Motorcraft or Nippondenso starter bolts right into the QuickTime bellhousing. Access can get very tight especially if you have a road race pan.
The T-56 Magnum’s shifter sits exactly where it is supposed to with adequate clearance.
If you think your T5 or TKO feels good, wait until you get the T-56 Magnum’s shifter in your hand. Nice tight crisp shifts without a missed shift.
GRAB IT… SHIFT IT… GO