Allison Transmissions

Automatic Models HT 750DR/HT 755DR up to 445 nhp (332 kW)

                                                        HT 750DR
                                                       Hydraulic
Net input power (max).............................445 hp (332 kW)
Input speed range................................1900 - 2500 rpm*
Net input torque (max)......................1435 lb ft (1946 N·m)
Vehicle weight (max)............Up to 80,000 lbs (36,287 kg) GVW
                                 and 130,000 lbs (58,967 kg) GCW
           * 1900 - 2600 with second gear start (2GS).  

                                                        HT 755DR
                         Allison Transmission Electronic Control
Net input power (max)............................445 nhp (332 kW)
Input speed range................................1700 - 2800 rpm
Net input torque (max)......................1435 lb ft (1946 N·m)
Vehicle weight (max)............Up to 80,000 lbs (36,287 kg) GVW
                                 and 130,000 lbs (58,967 kg) GCW  

Direct..............SAE 1 flywheel housing with flex plate drive
Remote.....Converter housing side pads, and rear housing top pad  

Type..........................Single-stage, 3-element, polyphase
Stall torque ratio.........TC 487-1.50; TC 488-1.70; TC 470-2.83;
                           TC 495-2.39; TC 496-1.78; TC 497-2.72; 
                                        TC 498-2.45; TC 499-1.91
Automatic lockup clutch..................Effective in all ranges
  

Type.........................Constant mesh, spur type, planetary

                                      HT 750DR          HT 755DR
Range                                  Ratios*           Ratios*
First..(manually selected).............7.97:1 ............7.97:1
Second.................................3.19:1 ............3.19:1
Third..................................2.02:1 ............2.02:1
Fourth.................................1.38:1 ............1.38:1
Fifth..................................1.00:1 ............1.00:1
Reverse..(17.22 optional)..............4.72:1 ..............4.72  

           * Gear ratio does not include torque converter multiplication.  

Converter driven (SAE 6-bolt)
Location...................Top, left side at 10 o'clock position
                                            (as viewed from rear)
Drive gear ratio................1.00 x turbine speed (all ranges)
Drive gear rating.................300 lb ft (407 N·m) continuous; 
                                400 lb ft (543 N·m) intermittent

Engine driven (optional) (SAE 8-bolt)
Location....converter housing: one at 1 o'clock position and one
                      at 8 o'clock position (as viewed from rear)
Drive gear ratio........1 o'clock position – 1.36 x engine speed;
                        8 o'clock position – 0.84 x engine speed
Drive gear rating.....................200 hp (149 kW) continuous; 
                                    260 hp (194 kW) intermittent  

Oil type.........................................Dexron III®, C4
Capacity 
     (excluding external circuit).....7.5 U.S. gals (28.5 liters)
                                                 (w/std. oil pan)
Filter............Full flow, replaceable element, remote mounted 
Cooler............................................Remote mounted 

(Filter and Cooler not furnished on transmission assembly but are supplied
 by vehicle manufacturer.)  

                                                       HT 750DR
Length.........................................41.0 in (1041 mm)
Width...........................................21.8 in (552 mm)
Height..........................................26.6 in (675 mm)
Weight (dry)..........................940 lbs (426 kg) (approx.)

                                                       HT 755DR
Length.........................................41.0 in (1041 mm)
Width...........................................21.8 in (552 mm)
Height..........................................26.6 in (675 mm)
Weight (dry)..........................940 lbs (426 kg) (approx.)

+NOTE: Vocational ratings may vary by vocation.   

	Designed for use with diesel engines up to 445 nhp (332 kW). Five forward ranges and one reverse, with fully automatic shifting in upper four ranges. First range is manually selected. This transmission model is best suited for medium- and heavy-duty vehicle applications.
	Clutches are multidisc design, oil-cooled, hydraulically-operated, and self-compensating for normal wear. Spur-type planetary gears are designed for strength, quietness and long life.
	Automatic lockup clutch, throttle-modulated for maximized fuel economy and enhanced engine braking. Automatic upshifting and downshifting within each drive range. Built-in inhibitors prevent downshifts or shifts into reverse unless vehicle speed is within an acceptable range.
	The Allison three-element torque converter provides smooth, shock-free operation. A choice of converters permits matching the HT 750DR and the HT 755DR to a wide variety of engines.
	Converter-driven power takeoff drive on right side of transmission (as viewed from the rear) is standard. Design is SAE 6-bolt.
	Optional engine-driven power takeoff is available in two locations - upper right and lower left sides, as viewed from rear. Design is SAE 8-bolt.
	Optional input retarder, with power absorption capacity of 365 nhp (272 kW) at 2100 RPM for vehicle downhill speed control.
	Provisions for neutral start switch, reverse signal switch, SAE regular -duty thread-type speedometer drive, electronic speedometer drive, and parking brake.
	Allison Transmission Electronic Controls provide: programmable features to perform vehicle and vocational requirements; built-in diagnostics which constantly monitor operation and facilitate the detection of problems if they occur; improved fuel economy; specific vehicle and vocation needs.
	7.0 inch oil pan is standard. Optional 6.0, 4.5 and 8.5 inch pans are available when ground clearance or heavy duty operation dictates their use.

	Dump Truck
	Refuse Hauler
	Lowboy Truck
	Hook & Ladder Truck
	Transit Mixer
	Crash, Fire, Rescue Truck
	Logging Truck
	Rear Loader (Refuse)
	Agricultural
	Construction Equipment Hauler
	Wrecker (Tandem Axle)
	Public Utility (All Wheel Drive Tandem Axle)
	Other applications are available.