TM-9-2320-272-23-3

TRUCK, 5-TON, 6X6, M939, M939A1, AND M939A2 SERIES TRUCKS (DIESEL)

TECHNICAL MANUAL; FIELD MAINTENANCE MANUAL; VOLUME 3 OF 5

SEPTEMBER 2012

TM-9-2320-272-23-3 - Page 323 of 1469

TRANSMISSION OIL COOLER PRESSURE TEST - Continued

NOTE

Refer to TM 9-2320-272-10 when performing Steps (12) through (20).

12.

Set parking brake.

WARNING

Ensure all personnel are clear from underside and front of vehicle before starting engine.

Transmission slipping into gear may cause vehicle to move. Failure to comply may result in

injury or death to personnel.

13.

Start engine and check oil cooler connections for leaks.

CAUTION

Do not maintain stalled condition for longer than 30-second intervals. Transmission oil may

overheat and cause transmission damage.

14.

Place transmission shift lever in 1-5 (drive) and operate engine at 1,200 rpm.

15.

Place transmission shift lever in N (neutral) and operate engine at normal operating temperature.

16.

Check transmission oil level.

17.

Operate engine at 1,650 rpm with transmission shift lever in N (neutral) and parking brake set. Check pressure

gauge and note reading.

18.

If pressure is less than 26 psi (179.2 kPa), check for hose or internal oil cooler leakage.

19.

If pressure exceeds 26 psi (179.2 kPa), check for cooler, cooler filter, or cooler hose restriction.

20.

Stop engine and disconnect gauge (Figure 2, Item 4) and hose (Figure 2, Item 2) from elbow

(Figure 2, Item 1).

21.

Install oil sampling valve (Figure 2, Item 3) in elbow (Figure 2, Item 1).

TM 9-2320-272-23-3

0374

0374-4