P0733 on Mazda
Gear 4 Incorrect Ratio
P0733 on Mazda vehicles indicates gear 4 incorrect ratio. Au7o has documented this code across 1 Mazda model — most commonly on 626. This code indicates the transmission control module found that the actual gear ratio in 4th gear is outside the acceptable range for that gear. It is detected by comparing transmission input speed against output speed while 4th gear is engaged. A mismatch typically signals the transmission is slipping in 4th gear or that a control/hydraulic fault is preventing proper engagement. Typical repair costs on Mazda range from $2,000 to $3,800, depending on the specific model and root cause.
Common Causes of P0733
- •Low or contaminated transmission fluid
- •Worn 4th-gear clutch packs or bands
- •Failing shift solenoid for 4th gear
- •Valve body or line pressure issues
- •Internal transmission mechanical wear
- •Restricted transmission filter
- •Faulty input or output speed sensor
P0733 on Mazda by Model
Mazda 626(1 issue)
- CD4E 4-speed automatic transmission premature failure1993-1997
The Ford-designed CD4E automatic transaxle fitted to 1993-1997 (5th-gen GE) 626s with an automatic is one of the most notorious weak points of the car. It runs hot, has undersized clutch packs and a fragile forward-clutch/valve-body design, and commonly fails anywhere from 60,000-100,000 miles. Both the FS 2.0L I4 and KL 2.5L V6 automatic cars used it. Repair shops have reported very high failure rates and the NHTSA/CarComplaints logs are dominated by transmission complaints for these years. A primary root cause was an inadequate factory transmission cooling circuit (a poorly designed radiator that did a bad job cooling the ATF). There was no recall, so owners bore the cost. The 626/MX-6 community regards a manual-transmission car as far more reliable.
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What does P0733 mean on Mazda?▼
P0733 stands for "Gear 4 Incorrect Ratio." This code indicates the transmission control module found that the actual gear ratio in 4th gear is outside the acceptable range for that gear. It is detected by comparing transmission input speed against output speed while 4th gear is engaged. A mismatch typically signals the transmission is slipping in 4th gear or that a control/hydraulic fault is preventing proper engagement. On Mazda specifically, this code is documented across 1 model.
What causes P0733 on Mazda vehicles?▼
Common causes on Mazda: Low or contaminated transmission fluid, Worn 4th-gear clutch packs or bands, Failing shift solenoid for 4th gear, Valve body or line pressure issues, Internal transmission mechanical wear. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P0733 on a Mazda?▼
Repair costs on Mazda range from $2,000 to $3,800, depending on the specific model and root cause.
Which Mazda models have P0733 documented?▼
Au7o has documented P0733 on 1 Mazda model: 626.