I have an x3 with transmission trouble code 55 (gear monitering 5) and code 145 (can torque reduction) trouble codes , I am a trans rebulder, I have torn and build this transmission and didn't find any internal problem with this unit any help

It could be many things;
Retrieve trouble code with a scanner.
1-Automatic transmission Oil level (Low).
2- If it's from a cold start overnight ...torque converter draining into oil pan when the torque converter is full of oil transmission will engage.
3- Internal defect like (One way clutch) freewheel (spinning) while it should lock
4- and more if not solve.
Hope it helps

Definitely transmission problems
P0740 Torque Converter Clutch Circuit Malfunction

P0730 OBD II Trouble Code

Unfortunately most transmission shops will say "needs a rebuild".
Sometimes you can get a low mileage transmission out of a wrecked car, but the install labor isn't cheap.

Since the transmission shifting and torque converter lock (cruise speeds) up are computer controlled you need to have a scanner hooked up that can read Transmission control module (TCM) fault codes. Also check for engine codes as this could be a misfire, but in that case the check engine light should be flashing while the engine is misfiring and set a fault code. If no codes of any kind are present in memory when the testing is done you almost certainly have a mechanical fault in the transmission like a malfunctioning torque converter clutch, but even that should set a fault code, so have the testing done.

P0740 - Torque Converter Clutch Malfunctionhttp://engine-codes.com/p0740.htmlForum CodePossible causes- Low transmission fluid level
- Dirty transmission fluid
- Faulty torque converter clutch solenoid valve
- Torque converter clutch solenoid valve harness or connectors
- Torque converter clutch solenoid valve circuit is open or shorted When is the code detected?Diagnostic trouble code P0740 is detected when TCM detects an improper voltage drop when it tries to operate the solenoid valve.

P0700 TCM has requested PCM to run on Check engine light to alert to a fault in the automatic transmission.

what trouble code you getting if you are getting code p1700 transmission system malfunction.could have internal transmission failure noise you hear could be transmission oil pump or torque converter failure, either one will cause transmission shift problems.

P0732 FORD - Incorrect Second Gear Ratio
Transmission in second gear and the ECM detected an incorrect gear ration. This diagnosis monitors actual gear position by checking the torque converter slip ratio calculated by Transmission Control Module (TCM) as follows:

Torque converter slip ratio = A x C/B

A: Output shaft revolution signal from revolution sensor
B: Engine speed signal from Engine Control Module (ECM)
C: Gear ratio determined as gear position which TCM supposes

If the actual gear position is higher than the position (2nd) supposed by TCM, the slip ratio will be more than normal. In case the ratio exceeds the specified value, TCM judges this diagnosis malfunction.

Symptoms
- Engine Light ON (or Service Engine Soon Warning Light)
- Incorrect transmission shifting

Possible causes
- Low transmission fluid level
- Dirty transmission fluid
- Shift solenoids
- Transmission mechanical problems
- Transmission hydraulic control circuit

Tech notes
Start by inspecting the transmission fluid level and condition, and change fluid if necessary.


Hope helps.

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P1514 Park/Neutral Position Switch High Load Neutral/Drive

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P1607 MIL Output Circuit

P1608 Automatic Transmission

P1609 Internal ECM Error

P1641 Fuel Pump Relay No. 1

P1646 Fuel Pump Relay No. 2

P1739 Automatic Transmission

P1775 Transmission Control Module MIL Circuit

P1776 Torque Reduction Request Signal

P1777 Torque Reduction Circuit

P1780 Automatic Transmission

P1781 Automatic Transmission

P1782 Automatic Transmission

P1783 Automatic Transmission

P1785 Automatic Transmission

P1790 Automatic Transmission

P1791 Automatic Transmission

P1792 Automatic Transmission

P1794 Automatic Transmission
P1796 Automatic Transmission
as you can no such code exists for a jaguar ,contact code reader manufacturer

This information is from my genuine service manual. I hope it is of help.
Non-turbo
Turbo
Sedan Wagon
Type 5-forward speeds with synchromesh and 1-reverse
Transmission gear ratio
1st 3.454 3.454
2nd 2.062 1.947
3rd 1.448 1.366
4th 1.088 0.972
5th 0.780 0.738
Reverse 3.333
Front reduction gear Final
Type of gear Hypoid
Gear ratio 4.111 3.900
Rear reduction gear
Transfer
Type of gear Helical
Gear ratio 1.000 1.100
Final
Type of gear Hypoid
Gear ratio 4.111 3.900 3.545
Front differential Type and number of gear Straight bevel gear (Bevel pinion: 2, Bevel gear: 2)
Center differential Type and number of gear
Straight bevel gear
(Bevel pinion: 2, Bevel gear: 2 and viscous coupling)
Transmission gear oil GL-5
Transmission gear oil capacity 3.5 2 (3.7 US qt, 3.1 Imp qt)

talk to your rebulder but i would think that you did not get the torque converter pushed all the way back on the pump when you installed the trans

1st thing to do is test the system for codes, the problem is most likely a failed or stuck shift solenoid indside the trans, have you ever serviced the trans, sometimes a fluid and filter cahnge will cure these kinds of issues.