July 01, 2020
Always Identify These Valve Bodies BEFORE You Start a Transmission Rebuild
Andrew Jessiman
Ford 6F50 & 6F55 Identification Guide
Ford 6F50 valve bodies can be misidentified from 6T70 valve bodies. Further, 6F50 early and late units are almost identical in appearance and cannot be interchanged. It is critical when ordering a remanufactured valve body to know which unit is installed.
6F50 vs. 6T70 Series Valve Body Identification
Look for these features to distinguish 6F50/55 units from 6T70 series valve bodies.
| 6F50 & 6F55 Valve Body Front View |
|---|
 |
| 6F50 & 6F55 Valve Body Back View |
|---|
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Early vs. Late 3-5-R Clutch Regulator Valves
Look for these numbers on the side of the valve body to distinguish between early and late valve styles.
| '09-Later |
|---|
BSAA5P Number is for FD6F50L, ’09-Later, 1.83 Ratio 3-5-R Clutch Regulator Valve
|
| '07–'09 |
|---|
BS7T4P Number is for FD6F50E, ’07–’09, 1.35 Ratio 3-5-R Clutch Regulator Valve
|
Learn More
Related Units
Related Parts
Required
Recommended
6F50, 6F55, 6T70 (Gen. 1), 6T75 (Gen. 1)
Oversized AFL/Solenoid Pressure Regulator Valve 124740-01
-
Helps cure:
- Solenoid performance codes
- Wrong gear starts
- Clutch failure
Required
Recommended
6F50, 6F55, 6T70 (Gen. 1), 6T75 (Gen. 1)
Oversized Pressure Regulator Valve Kit 124740-12K
-
Helps cure:
- Erratic line pressure
- Poor shift quality
- Burnt clutches
- Low converter & lube flow
- Overheating
- TCC apply & release concerns
Required
Recommended
6F50, 6F55, 6T70 (Gen. 1), 6T70 (Gen. 2), 6T75 (Gen. 1), 6T75 (Gen. 2), 6T80 (Gen. 2)
Isolator Valve Spring 124740-16
-
Helps cure:
- No line rise
- Line pressure instability
Required
Recommended
6F50, 6F55, 6T70 (Gen. 1), 6T70 (Gen. 2), 6T75 (Gen. 1), 6T75 (Gen. 2), 6T80 (Gen. 2)
O-Ringed End Plug Kit 124740-02K
Required
Recommended
6F50, 6F55, 6T70 (Gen. 1), 6T70 (Gen. 2), 6T75 (Gen. 1), 6T75 (Gen. 2), 6T80 (Gen. 2)
Isolator Valve Kit 124740-03K
Required
Recommended
6F50, 6F55, 6T70 (Gen. 1), 6T70 (Gen. 2), 6T75 (Gen. 1), 6T75 (Gen. 2), 6T80 (Gen. 2)
Oversized TCC Regulator Valve Kit 124740-24K
-
Helps cure:
- Code P0741, P0742
- Harsh TCC apply
- TCC slip
- Loss of fuel economy
- Low TCC apply pressure
- Overheated fluid & TCC lining
Required
Recommended
6F50, 6F55, 6T70 (Gen. 1), 6T75 (Gen. 1)
Oversized 2-6 Clutch Regulator Valve Kit 124740-17K
-
Helps cure:
- 1-2 Flare
- 5-6 Flare
- 2nd Slip
- 6th Slip
- No 2nd
- No 6th
- Ratio codes
- 2-6 Clutch burned
- Erratic shift timing
Required
Recommended
6F50, 6F55, 6T70 (Gen. 1), 6T75 (Gen. 1)
Oversized 3-5-R Clutch Regulator Valve Kit 124740-21K
Replaces 1.83 ratio OE valve with .335" dia. small spool.
-
Helps cure:
- 2-3 Flare
- 4-5 Flare
- Delayed Reverse
- Reverse slip
- 3-5-Reverse clutch burned
- Ratio codes
- Bind-up
- Burnt Reverse clutch
Required
Recommended
6F50, 6F55, 6T70 (Gen. 1), 6T70 (Gen. 2), 6T75 (Gen. 1), 6T75 (Gen. 2), 6T80 (Gen. 2)
Oversized TCC Control Valve Kit 124740-14K
-
Helps cure:
- Excess TCC slip
- Low cooler flow
- Overheating
- TCC apply & release concerns
- Low converter & lube flow
- TCC apply codes
- TCC lining failure
Required
Recommended
6F50, 6F55, 6T70 (Gen. 1), 6T75 (Gen. 1)
Oversized 3-5-R Clutch Regulator Valve Kit 124740-26K
Replaces 1.35 ratio OE valve with .390" dia. small spool.
-
Helps cure:
- 2-3 Flare
- 4-5 Flare
- Delayed Reverse
- Reverse slip
- 3-5-Reverse clutch burned
- Ratio codes
- Bind-up
Required
Recommended
6F50, 6F55
Remanufactured Valve Body FD6F50L
Fits '09-later units with 1.83 ratio 3-5-R. Sold without transmission control module.
Required
Recommended
6F50, 6F55
Remanufactured Valve Body FD6F50E
Fits '07–'09 units with 1.35 ratio 3-5-R. Sold without transmission control module.
Required
Recommended
6F50, 6F55, 6T70 (Gen. 1), 6T70 (Gen. 2), 6T75 (Gen. 1), 6T75 (Gen. 2), 6T80 (Gen. 2)
TCC Regulator Valve Kit 124740-31K
Required
Recommended
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