NHTSA ID Number: 10201063
Manufacturer Communication Number: TSB 21-2148
Summary
Some 2020-2021 Mustang
GT500 vehicles may exhibit a transmission fluid leak caused by improperly seated or cracked transmission cooler tubes attached to the transmission case. This may be due to the retaining bolts being cross threaded causing the seals to leak and/or crack the lines. If the threads in the transmission case that the cooler tube retaining bolts go into are damaged, it is not necessary to replace the transmission. These threads can be repaired. To correct the condition, follow the Service Procedure to repair these threads and replace the tubes.
This bulletin supersedes 21-2108. Reason for update: New Part/Procedure For Same Condition
2020-2021 Mustang GT 500
Summary
This article supersedes TSB 21-2108 to update the issue, action, and Service Procedure.
Issue: Some 2020-2021 Mustang GT500 vehicles may exhibit a transmission fluid leak caused by improperly seated or cracked transmission cooler tubes attached to the transmission case. This may be due to the retaining bolts being cross threaded causing the seals to leak and/or crack the lines. If the threads in the transmission case that the cooler tube retaining bolts go into are damaged, it is not necessary to replace the transmission. These threads can be repaired. To correct the condition, follow the Service Procedure to repair these threads and replace the tubes.
Action: Follow the Service Procedure steps to correct the condition on vehicles that meet all of the following criteria:
- 2020-2021 Mustang GT500
- Transmission fluid leak caused by improperly seated or cracked transmission cooler tubes with damaged cooler tube retaining bolt threads in the transmission
NOTE: Part quantity refers to the number of that service part number required, which may be different than the number of individual pieces. Service part numbers contain 1 piece unless otherwise stated. “As Needed” indicates the part is required but the number may vary or is not a whole number; parts can be billed out as non-whole numbers, including less than 1. “If Needed” indicates the part is not mandatory.
Parts
| Service Part Number | Quantity | Description | |
| KR3Z-7C013-A | 1 | Transmission Fluid Filter Housing Cover | – |
| KR3Z-7R081-C | 1 | Transmission Fluid Cooler Tube | – |
| Obtain Locally | 1 | Thread Repair Kit | – |
| XT-14-L | As Needed | Motorcraft® Dual Clutch Transmission Fluid | – |
| Parts To Inspect And Replace Only If Necessary | |||
| W721914-S450 | If Needed | Transmission Fluid Cooler Tube Retaining Bolt | Package Contains 4 Pieces |
| 5L7Z-7D285-A No products found. | If Needed | Backing Ring | Package Contains 2 Pieces |
| 5L7Z-7J324-A No products found. | If Needed | Band Seal | Package Contains 2 Pieces |
| KR3Z-7C045-B | If Needed | Transmission Oil Filter Kit | – |
Service Procedure
1. Determine which fluid cooler tube port on the transmission has damaged threads.
(1). If the front port is damaged, replace the transmission fluid filter cover. Refer to Workshop Manual (WSM), Section 307-01B. Proceed to Step 2.
(2). If the rear port is damaged, proceed to Step 2.
2. Remove and discard the transmission fluid cooler tubes. Refer to WSM, Section 307-02B, Removal and Installation, Transmission Fluid Cooler Tubes, Steps 1,2,3,4,8,9,10,11.
3. Cover the fluid cooler tube ports in the side of the transmission to prevent any debris from entering the transmission.
4. Using a M6 x 1 x 12mm thread repair insert kit, repair the damaged threads in the transmission case. Use the instructions contained with the kit to install the thread repair kit.
5. Thoroughly clean the repair area.
6. Install the new rear transmission fluid cooler tubes. Refer to WSM, Section 307-02B. Replace the rear transmission fluid cooler tube retaining bolt(s) as necessary.
7. Verify the proper transmission fluid level. Add fluid as necessary.
8. Make sure no leaks are present after making the repair. If any leaks are found, refer to WSM, Section 307-01B.
2 Affected Products
Vehicle
1 Associated Document
Manufacturer Communications
21-2148
30 August 2021
NHTSA ID Number: 10191174
Manufacturer Communication Number: TSB 21-2108
Summary
Some 2020-2021 Mustang GT500 vehicles may exhibit a transmission fluid leak caused by improperly seated transmission cooler tubes attached to the transmission case. If the threads in the transmission case that the cooler tube retaining bolts go into are damaged, it is not necessary to replace the transmission. These threads can be repaired. To correct the condition, follow the Service Procedure to repair these threads.
1 Associated Document
Manufacturer Communications
21-2108
09 April 2021
MC-10191174-0001.pdf 105.663KB
- The information below is per-pack only
- Package Weight : 32.2817248764489 pounds
- Provides exceptional drivetrain protection
- Made to provide the perfect lubricant solution for your needs
- Designed with innovative manufacturing techniques
- Package Weight : 32.2817248764489 pounds
- Provides exceptional drivetrain protection
- Made to provide the perfect lubricant solution for your needs
- Designed with innovative manufacturing techniques
- Formulated with premium friction modifiers to ensure smooth shifting performance under variable driving conditions
- Formulated with premium synthetic base oils to minimize thermal breakdown and deposits
- Advanced anti-wear technology to better prevent gear wear
- Excellent anti-shudder durability
- Superior Formulation: Full synthetic, PAO / Ester based formulation with extensive testing and performance data - far exceeding OEM performance requirements
- Wide Compatibility: Compatible with a wide range of Dual Clutch Transmissions (DCT), including those manufactured by ZF, Mercedes Benz, Ford XT-11-QDC, VW / Audi DSG and DSG-2 G060162A2 (DSG Transmissions), Ford, Subaru, Bugatti, Ferrari, BMW, and many others
- Exceptional Longevity: Lasts over 300,000 miles and is thus classified as a “fill-for-life” product in properly sealed transmissions unless the OEM specifies otherwise
- Unmatched Shifting Performance: Delivers flawless shifting, eliminates slippage, ensures optimal functionality in all conditions, maintains cold flow down to -60°F, and is compatible with all seal materials, both synthetic and natural rubber
- Outstanding Shifting: Effectively prevents gear scuffing, ensuring smooth operation and enhanced performance even under high torque and horsepower racing conditions
- Meets the challenging demands of dual clutch transmissions
- Enhanced anti-shudder protection for smooth shifting and maximum power transfer while preventing wear of the gears and synchronizers.
- Advanced anti-wear technology improves durability to help extend the life of your transmission
- Provides better oil flow in both low and high temperatures
- Full synthetic formula with advanced additives protects against transmission breakdown better than conventional fluids
Last update on 2026-06-18 / Affiliate links / Images from Amazon Product Advertising API
SEOCONTENT-START
Warranty Status: Eligible under provisions of New Vehicle Limited Warranty (NVLW)/Service Part Warranty (SPW)/Special Service Part (SSP)/Extended Service Plan (ESP) coverage. Limits/policies/prior approvals are not altered by a TSB. NVLW/SPW/SSP/ESP coverage limits are determined by the identified causal part and verified using the OASIS part coverage tool. Labor Times Description Operation No. Time 2020-2021 Mustang GT500: Inspect And Replace The Transmission Fluid Filter Cover And Fluid Cooler Tubes, Includes Time To Adjust Transmission Fluid Level, Front Port Only (Do Not Use With Any Other Labor Operations) 212148A 1.4 Hrs. 2020-2021 Mustang GT500: Inspect And Repair The Threads On The Rear Port And Replace The Fluid Cooler Tubes, Includes Time To Adjust Transmission Fluid Level, Rear Port Only (Do Not Use With Any Other Labor Operations) 212148B 1.4 Hrs. 2020-2021 Mustang GT500: Inspect And Repair The Threads On The Rear Port, Replace The Transmission Fluid Filter Cover And Replace The Fluid Cooler Tubes, Includes Time To Adjust Transmission Fluid Level (Do Not Use With Any Other Labor Operations) 212148C 1.6 Hrs. Repair/Claim Coding Causal Part: 7003 Condition Code: 24
**************************************************************************************************************
SEOCONTENT-END
This product presentation was made with AAWP plugin.