P0733: How to Diagnose & Fix — Gear 3 Incorrect Ratio

How to Fix

Have a Ford dealer confirm the symptom and check for later PCM/TCM software. Bulletin 23-2352 specifies a PCM/TCM software update and adaptive learning drive cycle first. If the condition remains and one of the listed codes is stored, the main control valve body is serviced; without codes, vehicles built on or before 1-Nov-2021 first get a transmission solenoid strategy reprogram, and later builds go to the valve body. Ford notes shifts can feel firmer than normal for several days while the adaptive strategy relearns. Normal warranty rules apply; this is not a recall or a promise of free repair.

How to Fix

Replace or rebuild the mechatronics unit. In some cases, a transmission adaptation reset via ISTA can resolve early-stage symptoms. Severe cases require full mechatronics replacement, which involves dropping the transmission. Fluid change every 30k miles helps extend life.

How to Fix

Confirm the VIN build record, 545RFE sales code DGQ, stored transmission DTCs, and TCM event data. Read digits three through six of the TCM barcode; TSB 08-016-05 identifies 0984 through 0405 as the suspect controller build range. If the vehicle or controller date is outside scope, the bulletin does not apply and the transmission complaint needs its normal diagnostic path. For an in-scope vehicle, use the bulletin's P0868/gear-ratio decision path and compare desired, scan-reported actual, and mechanically measured line pressure with correct fluid level and temperature. Inspect wiring, connectors, cooler lines, leaks, and engine driveability first. The repair may involve the TCM and, when low pressure was present, inspection for clutch-disc damage; it is not a universal retail-parts fix.

Owner tips & cautions

• WarningDo not apply this TSB to every 45RFE/545RFE complaint. It requires a 2004 WJ/WG, 4.7L/4.7L H.O., sales code DGQ, the bulletin's vehicle build range, a listed DTC, and a suspect TCM date code.
• TipPreserve the TCM event data before clearing codes. The bulletin uses that data and the controller barcode date to separate a controller fault from actual low pressure and clutch damage.
• WarningA filter kit, ATF, cooler, Sonnax valve, separator plate, or solenoid pack is not a complete answer to this card. The old links represented different failure paths and have been removed.

How to Fix

Diagnose first: many cars respond to a TCM software update plus a full drain-and-fill (not a flush) with Volvo JWS 3309 / Toyota T-IV fluid, repeated 2-3 times, and replacement of the transmission fluid filter and pan gasket. Volvo also issued updated shift-adaptation software for the AW55-50SN. If the TCM itself has failed, it can often be rebuilt/resoldered by a specialist far cheaper than a dealer unit, but the replacement module must be programmed to the car. Once clutch material is in the fluid or the car has lost drive, a rebuilt or remanufactured transmission with an updated valve body is the only durable fix. Preventively, change the fluid every 40-50k miles regardless of the 'lifetime' claim.

How to Fix

Confirm with a scan tool for ratio-error codes plus a road test checking reverse and 3rd/5th engagement. The repair is a transmission teardown - replace the 3-5-R wave plate with the updated hardened design, replace the clutch pack, and flush or replace the valve body and cooler lines because of debris. Most shops quote a remanufactured 6T40 as the practical fix. When rebuilding, inspect the 3-5-R drum splines, which are usually damaged when the plate breaks; the updated plate still fails in some units, so rebuilders also use aftermarket drum-saver kits.