A/T - THM 440-T4 Second Gear Starts
Bulletin 87-7440-9Date Aug. '87
Ref. No. 87-165-7440
Corp. Ref. No. 777132
SUBJECT: SECOND GEAR STARTS
MODELS AFFECTED: 1984-1987 THM 440-T4 (ME9)
FIGURE 1 - THM 440-T4 TRANSAXLE IDENTIFICATION INFORMATION:
BULLETIN COVERS
A 1984-1987 vehicle equipped with a THM 440-T4 (Figure 1) may start out in 2nd gear instead of 1st gear. This condition could occur intermittently or all the time.
SERVICE ACTION
High line pressure could be a cause by holding too much governor pressure and not allowing the 1-2 shift valve to downshift. Check line pressure and governor pressure. Governor pressure should be below 3.0 psi at 0 mph.
FIGURE 2:
If the governor pressure is okay, the 1-2 shift valve (331) may be stuck in the upshifted position. Remove the control valve assembly and check for a sticking 1-2 shift valve (331), 1-2 throttle valve (332), or the 1-2 throttle valve spring (333) caused by the 1-2 throttle valve bushing retainer (390) pushed in too far. The retainer should be installed flush with the machined surface of the valve body (Figure 2).
SERVICE MANUAL REFERENCE
Refer to the THM 440-T4 (ME9) Automatic Transaxle Unit Repair Section in the appropriate Service Manual.
SERVICE NOTES
For 1985 CP, CW or HT THM 440-T4 transaxle models, refer to Corporate Bulletin 857610.