A/T - Erratic or No Upshifts

Number 83-T-59 Section 7 Date 10/83
Subject: ERRATIC OR NO UPSHIFTS - THM 700-R4 TRANSMISSION
In diagnosing any THM 700-R4 transmissions for erratic or no upshifts, the cause may be from a worn governor gear. The cause of the worn governor gear may be from one or more of the following conditions:

1. The output shaft to input carrier assembly snap ring came off.

2. Metal scale on the output shaft gear.

3. The governor dowel pin dimension may be incorrect.

4. An incorrect governor gear may have been installed.

When servicing any THM 700-R4 transmission for an erratic or no upshift condition, refer to the following diagnosis chart.

Follow guidelines given in your Service Manual for servicing the transmission governor gear.

Figure 1:

CONDITION CAUSE CORRECTION
1. Governor gear is worn in an "Apple 1. Flash, scale or nicks on the output 1. Replace governor gear (part number Core" shape (see Figure 1).. shaft gear. 8642928). Wire brush output shaft
gear to remove scale of flash. Replace output shaft if nicked.
2. Incorrect governor gear (THM 300C 2. Replace governor gear (part numtype). ber 8642928). DO NOT use THM
300C type as replacement.

Figure 2:

Figure 3:

2. Governor gear is worn in the middle, 1. The governor dowel pin is located 1. Replace the transmission case. but on one side only (see Figure 2). too far into its case bore. (See Check replacement case for correct Figure 3 for correct dimension.) dimension.
2. Governor sleeve stuck in case bore. 2. Replace governor assembly and transmission case.
3. The output shaft toinput carrier 3. Disassemble the transmission, resnap ring is loose or has come off. place the output shaft to input
The output shaft has moved rear carrier snap ring (part number
ward. 8642230).

Figure 4:

Figure 5:

3. Governor gear is worn at the edge The governor dowel pin is located too Arbor press the dowel pin into the case of the gear on one side only (see far out of its case bore. (Refer to to the correct dimension (refer to Figure 4). Figure 3 for correct dimension). Figure 3).

4. Governor gear is worn slightly, 1. The incorrect governor gear was 1. Replace the governor gear (part the entire length of the gear (see installed. number 8642928). DO NOT use
Figure 5). a THM 350C gear as a replacement
gear.