Why Your 6.7L Super Duty May Need Another PCM Reflash

Yes, the second software update is real, but it is not required for every truck that completed the first recall. Ford recall 26S17, federally identified as NHTSA campaign 26V158000, covers selected 2020–2022 6.7L diesel trucks whose earlier 24S78 repair may have installed the wrong PCM software version. The free remedy is another PCM reflash—not routine high-pressure fuel-pump replacement.

A model year, 6.7L engine, and completed 24S78 repair only place a truck in the possible screening group. Ford assigns 26S17 by VIN. Check both Ford and NHTSA before scheduling, especially because NHTSA generally removes completed recalls from its open-recall results.

Choose the truck and its 24S78 repair status; the checker shows whether it fits the reported 26S17 screening group and what to request next.

26S17 Corrects an Earlier Recall Repair

The original high-pressure fuel-pump campaign was 24S78, or NHTSA 24V957000. It addressed possible pump failure associated with aged biodiesel deposits and covered approximately 295,449 vehicles, according to WardsAuto’s report on the original recall.

The documented 24S78 remedy included PCM and transmission control module software updates. Ford later determined that the repair process could leave certain trucks with a prior-level PCM calibration that lacked the intended correction.

The follow-up campaign, 26S17/26V158000, covers a reported 7,105 trucks, according to Autoblog’s campaign report. It directs the dealer to install the correct PCM software. It does not list another TCM update.

This makes 26S17 a remedy-integrity campaign. It does not identify a newly discovered pump defect, and it does not mean every 24S78 repair failed. The much smaller follow-up population consists of selected VINs that may not have received the intended software protection.

Do not confuse 26S17 with a “second notice” for 24S78. The original campaign used staged owner notifications while its remedy was being prepared. The 26S17 letter identifies a separate campaign and another dealer visit for the affected VIN.

The Corrected PCM Software Addresses Biodiesel Deposits

Aged biodiesel deposits may form on drivetrain roller components inside the high-pressure fuel pump. Those deposits can interfere with pump operation and contribute to failure.

The corrected PCM software is reported to increase high-pressure pump cooling and limit the formation of aged biodiesel deposits. Ford’s explanation of the programming problem and corrected software was summarized by Kelley Blue Book.

Public recall documents do not provide the old and corrected calibration numbers, detailed control logic, calibration tables, or a universal procedure owners can use to verify the software independently. If a dealer or scan tool displays a calibration identifier, there is no published recall version in the available record against which an owner can reliably compare it.

After the repair, keep the zero-balance invoice and ask the dealer to identify the VIN, campaign 26S17, completion date, and PCM programming performed. The paperwork should say more than “fuel-pump recall completed,” because several Ford campaigns involve different pumps and remedies.

A Completed 24S78 Repair Does Not Settle Eligibility

The reported 26S17 screening population includes selected trucks with the 6.7-liter diesel engine:

• 2020–2022 Ford F-250, F-350, F-450, and F-550
• 2021–2022 Ford F-600
• 2022 Ford F-750

Gasoline engines are outside the reported diesel campaign description. The published range also does not mean every 6.7L truck in those model years is affected.

Three facts still do not prove that 26S17 applies: owning a listed model, having the 6.7L engine, and having completed 24S78. The final determination is VIN-specific. The NHTSA record for a 2021 F-250 SD confirms both campaigns for that vehicle category but not for every individual 2021 F-250.

The timing of the first repair also does not provide a published eligibility cutoff. A repair before or after a particular notification date cannot substitute for a VIN check. If recent dealer paperwork and online results conflict, ask the dealer to check Ford’s internal campaign status for the VIN and document the answer.

The Recall Sequence Explains the Second Letter

Ford initiated 24S78 in late 2024. An interim notice was sent in January 2025 while the final remedy was pending. The NHTSA vehicle record says completed-remedy owner letters were mailed on January 23, 2026.

Ford reported 26S17 to NHTSA on March 17, 2026. Affected VINs became searchable through NHTSA on March 18. Secondary reporting identified March 30 as the planned start of notification, while the official vehicle record lists April 7 as the mailing date.

Those March 30 and April 7 dates describe a planned start and recorded mailing date rather than competing versions of the repair. They also are not published repair-date cutoffs for deciding whether an individual truck received the wrong calibration.

Owners can review the federal records for 26V158000 and the original 24V957000 campaign. An open 26S17 result means the follow-up remains incomplete for that VIN. A completed campaign normally will not remain visible in NHTSA’s standard open-recall results.

Pump Symptoms Require More Than an Undocumented Reflash

Reported warning signs include extended cranking, a no-start condition, unusual fuel-system or engine-compartment noise, reduced power, an illuminated check-engine light, stalling, and loss of motive power.

Extended cranking and no-start usually appear while the truck is parked. Stalling or loss of motive power while driving creates the principal safety concern because it can increase crash risk.

A truck with symptoms should not arrive as an undocumented software-only appointment. Tell the service adviser when the problem began, whether it occurs cold or hot, how long the engine cranks, whether power loss occurred under load, and whether the engine restarted after stalling. Provide any warning messages or diagnostic trouble codes already recorded.

Ask for every symptom to be written on the repair order even if the technician cannot reproduce it. A symptomatic truck may need mechanical diagnosis in addition to the recall programming.

The recall information does not establish one universal drive-or-do-not-drive rule. If the truck is stalling, losing power, or failing to start, contact Ford or an authorized dealer and describe its present condition before driving it to the appointment.

The Reflash Does Not Repair Existing Pump Damage

The 26S17 remedy installs the correct preventive PCM software. Available recall information does not describe routine high-pressure fuel-pump replacement under this campaign.

The update should not be assumed to remove existing deposits, reverse mechanical wear, repair damaged roller components, restore a failed pump, or resolve every hard-start and reduced-power complaint. Correct programming and mechanical pump condition are separate questions.

That does not establish that an owner can never receive additional diagnosis or potentially covered work. Public recall information does not provide Ford’s pump-inspection procedure, replacement criteria, or coverage rules for every related failure. The dealer must make a VIN- and condition-specific determination.

For a symptomatic truck, request a repair order showing the reported symptoms, diagnostic trouble codes, technician findings, 26S17 programming, additional diagnosis, recommended mechanical repairs, and final recall-completion status. No supported universal repair time is available for 26S17, so turnaround must be confirmed with the servicing dealer.

Check Both Recall Systems Before Scheduling

Enter the 17-character VIN in the official Ford recall portal and NHTSA’s recall lookup. Save dated screenshots or printouts from both systems.

If 26S17 appears open, call an authorized Ford dealer, provide the VIN, and reference Ford recall 26S17. Bring the earlier 24S78 invoice if available. The correct PCM software is installed at no charge under the recall.

If 26S17 does not appear, confirm that the VIN was entered correctly. Recently announced campaigns can take time to appear, while repaired recalls generally disappear from NHTSA’s open-recall results. A blank result is not a complete repair history.

When Ford, NHTSA, and dealer records disagree, preserve each dated result and ask the dealer or Ford to confirm the VIN-specific campaign status in writing. Ford customer service can be reached at 1-866-436-7332; reference 26S17.

Keep 26S17 Separate From the Low-Pressure Pump Recall

Ford campaign 25S75, federally identified as 25V455000, concerns a separate low-pressure fuel-pump issue. For affected Super Duty vehicles, its reported remedy is low-pressure pump replacement rather than PCM programming.

By contrast, 24S78 and 26S17 concern protection related to the diesel high-pressure pump and aged biodiesel deposits. The first campaign called for PCM and TCM updates; the follow-up calls only for the correct PCM software.

If a service history says only “fuel-pump recall,” ask which campaign was completed. The Ford and NHTSA numbers should appear on the final invoice.

Owners who previously paid for a related repair may ask Ford about reimbursement. Ford states generally that customers who paid for work later associated with a recall may be eligible, but reimbursement is not automatic and campaign-specific eligibility rules are not provided in the available public information. Retain the paid invoice, proof of payment, diagnosis, VIN, and recall records for Ford’s review.

A truck with an open 26S17 and no symptoms needs the free PCM correction. A truck with an open 26S17 and pump symptoms needs the correction plus documented diagnosis. A truck that completed 24S78 but does not show 26S17 should not be assumed to need another update unless Ford confirms that the VIN is included.