TM-9-2350-274-BD

M109/M110/M578 VEHICLES HOWITZER, MEDIUM, SELF-PROPELLED FULL-TRACKED

TECHNICAL MANUAL; OPERATORS, ORGANIZATIONAL DIRECT SUPPORT AND GENERAL SUPPORT MAINTENANCE

JANUARY 1984

TM-9-2350-274-BD - Page 104 of 219

TM 9-2350-274-BD

CHAPTER 7

POWERTRAIN/STEERIN G

BDAR FIXES SHALL BE USED ONLY IN COMBAT

AT THE DISCRETION OF THE COMMANDER

AND SHALL BE REPAIRED BY STANDARD MAINTENANCE PROCEDURES

AS SOON AS PRACTICABLE AFTER THE MISSION IS COMPLETED.

SECTION L General

7-1. General.

The M109/M110/M578 series powertrain (transmission and transfer assemblies) transmits power from the

engine through the transfer assembly to the transmission input spur gear which is splined to the

transmission input shaft. The input spur gear operates the driven spur gear to which the torque converter

drive gear is splined. The torque converter delivers two branches of power, vehicle drive and steering.

The transmission is hydro-mechanically operated and delivers power to the left and right final drive

sprockets. The transmission provides four forward and two reverse speeds, and steering through a

differential action.

7-2. Assessment Procedure.

a. Pre-conditions: Vehicle brakes should be in working condition. The vehicle engine must run to

assess the powertrain using this procedure.

b. Visually inspect

Damage found to:

-housings . . . . . . . . . . . . . . . . . . go to TM 9-2350-276-BD

No damage

-drives . . . . . . . . . . . . . . . . . . . . go to para 7-7

found

-linkages . . . . . . . . . . . . . . . . . . go to para 7-6

c. Start engine

Damage found to:

to operate;

observe operation

No damage

-forward gears . . . . . . . . . . . . . . go to para 7-4

found

-reverse gears . . . . . . . . . . . . . .

. go to para 7-4

-steering capability . . . . . . . . . . . . go to para 7-6

d. Check powertrain/steering performance

Change 1

7-1