Allison Transmission HT 750DR

Operator’s Manual
AT, MT, HT Series
On-Highway Transmissions
OM1334EN

Allison Transmission HT 750DR Specifications

General

Brand	Allison Transmission
Model	HT 750DR
Category	Microphone system
Language	English

Summary

Warnings, Cautions, and Notes

WARNING Definition

Defines the meaning and use of "WARNING" in the manual for safety.

CAUTION Definition

Defines the meaning and use of "CAUTION" in the manual for equipment protection.

Care and Maintenance

General Inspections and Problem Prevention

Covers periodic inspections, preventing major issues, and keeping the transmission clean.

Fluid Level and Condition Checks

Details procedures for checking transmission and dropbox fluid levels and condition.

Fluid and Filter Maintenance

Specifies fluid types, viscosity, and change intervals.

Allison Automatic Description

Torque Converter Operation

Explains the function and components of the torque converter in Allison automatics.

Lockup Clutch Functionality

Shift Selectors Overview

Range Selection: AT 5001500 Series with Park

Range Selection: AT 5001500 Series with Park (contd)

Range Selection: AT 5001500 Series without Park; MTHT Models

Range Selection: AT 5001500 Series without Park; MTHT Models (contd)

Range Selection: MT 650; MT(B) 653 DR

Range Selection: MT 650; MT(B) 653 DR (contd)

Range Selection: HT 750 CR, HT 754 CR, MT(B) 654 CR

Drive (D) Position

Range Selection: HT 750 CR, HT 754 CR, MT(B) 654 CR (contd)

Range Selection: HT 750 DR, HT 750 DR DB

Reverse (R) Operation

Ranges 2-5 Operation

Range Selection: HT 750 DR, HT 750 DR DB (contd)

Driving Tips

Throttle Control

Downshift Inhibit Feature

Operating in Cold Weather

Provides essential precautions and procedures for operating the transmission in cold temperatures.

Using Engine for Downhill Braking

Using the Hydraulic Retarder

Details the operation and safety precautions for using the hydraulic retarder system.

Driving on Ice or Snow

Transmission Temperatures

Lists important transmission fluid temperature ranges for safe operation.

Transmission Fluid Check Procedure

Cold Fluid Check

Details the steps for checking transmission fluid level when the transmission is cold.

Hot Fluid Check

Details the steps for checking transmission fluid level when the transmission is at operating temperature.

Dropbox Fluid Check Procedure

Keeping Fluid Clean

Recommended Fluid for Non-MT 643 R Transmissions

Specifies the correct fluids and viscosity grades for non-MT 643R transmissions.

Recommended Fluid for MT 643 R Transmissions

Fluid and Filter Change Intervals

Fluid Contamination

Identifying Metal Particles

Coolant Leakage and Fluid Analysis

Fluid Analysis for Optimization