Can you tell me about the TCM vs the PSM or
ECM? Can I get a rebuilt TCM?
What other things do you suggest it could be?
Read
@doug7740's post above. Also, this thread discusses hard shifts-
https://forums.fordthunderbirdforum.com/threads/transmission-shifting-rough-2004-thunderbird.7821/
If the upshifting issue is the
PCM, use the link above to buy a replacement. They are also programmed with the latest software that addresses other shifting issues. I'm not aware of anyone that rebuilds them, just rebuilds for the
FEM.
Also, another discussion here-
https://forums.fordthunderbirdforum.com/threads/2004-transmission-shift-flare.14391/
Search the site for hard shift.
Also from-
https://www.yourmechanic.com/articl...e-code-gear-3-incorrect-ratio-by-andrew-quinn
P0733 Code Definition
Gear 3 incorrect ratio is the technical definition of the P0733 trouble code
What the P0733 code means
The P0733 code means that the powertrain control module (
PCM) has detected something unusual with the ratio of the third gear in the vehicle’s transmission. This will usually have to happen multiple times before a trouble code will be stored.
The powertrain control module uses the information it receives from multiple sensors that gather and calculate data, such as vehicle speed, throttle position, engine RPM, and other measures to determine which ratio a particular gear should have. If there is a difference between the desired gear ratio and the actual gear ratio (multiple times) a
Check Engine Light will be illuminated.
What are the causes of the P0733 code?
Some of the potential causes of the P0733 code may include:
A faulty shift solenoid
A faulty powertrain control module
A faulty transmission module (if applicable)
Low
transmission fluid
Skipping over
transmission fluid maintenance
Debris inside transmission causing a restriction in the flow of
transmission fluid
Internal transmission damage
What are the symptoms of the P0733 code?
Just about all possible negative symptoms a transmission can have are possible with this trouble code. Some of these symptoms you may see include:
Transmission slippage
Hard shifts
Transmission
overheating
Transmission may not shift in or out of a particular gear
How does a mechanic diagnose the P0733 code?
The first thing a mechanic is likely to do when diagnosing a P0733 code would be to check the level and condition of the
transmission fluid. If the
transmission fluid is low or dirty, this could be the first sign of the problem, and the fluid should be replaced or topped off as necessary.
If the fluid level and condition are acceptable, the next thing the mechanic may do is perform a test drive to confirm the customer’s symptoms. The diagnosis of this code is likely to involve the complete teardown of the transmission, or at least the removal of the transmission pan. Some of the
parts of the transmission that may need to be inspected or tested are not accessible without transmission disassembly.
Common mistakes when diagnosing the P0733 code
A mistake that could easily be made when diagnosing a P0733 code would be to have the transmission replaced assuming that internal damage has occurred. It is important to be certain that the transmission is faulty before replacing it. For whichever route gets taken, the labor will be expensive, so it is best to make sure the transmission actually needs to be replaced before adding even more money to the bill.
How serious is the P0733 code?
The P0733 code is very serious. This code can cause a number of drivability issues and is very likely to leave the driver stranded on the side of the road somewhere. It is best to have this code diagnosed and repaired as soon as possible to avoid further damage to the vehicle and to prevent being stranded anywhere.
What repairs can fix the P0733 code?
Repairs that can fix a P0733 code would include:
Replacing a shift solenoid
Replacing the powertrain control module
Replacing the transmission module (if applicable)
Adding or replacing the
transmission fluid and filter
Overhauling the current transmission
Installing a brand new transmission
Additional comments regarding the P0733 code
Complete transmission replacement is worst case scenario for a P0733 code. Be sure to rule out all other less expensive possibilities before replacing the transmission. This could save dividends in the long run.
