Mack Anthem An (4), Mack Pioneer Pr (4), model years 2026 to 2027. Filed by Mack Trucks, Inc. and reported to NHTSA on 28 September 2026. 850 vehicles potentially affected.
What the notice says Mack Trucks, Inc. (Mack) is recalling certain 2026-2027 Anthem AN (4) and Pioneer PR (4) vehicles equipped with a tanker application package. Inaccurate axle load calculations may cause reduced braking performance while transporting smoothbore tanker trailers.
Is your vehicle included? Check with your VIN at NHTSA, or ask a dealer. This page is an independent copy of the notice, kept so you can see what changed after it was published. It is not the authority, and the authority’s own text is the one to act on.
Mack's own number for this recall: SC0500. That is the number on the owner letter and on the dealer paperwork. 26V620 is the number NHTSA gave the same campaign, and the number this page is filed under. They are one recall, written two ways.
What owners ask about this recall
- Which vehicles does recall 26V620 cover?
- Mack Anthem An (4), Mack Pioneer Pr (4), model years 2026-2027.
- What is wrong with them?
- Mack Trucks, Inc. (Mack) is recalling certain 2026-2027 Anthem AN (4) and Pioneer PR (4) vehicles equipped with a tanker application package. Inaccurate axle load calculations may cause reduced braking performance while transporting smoothbore tanker trailers.
- What can happen if it is not put right?
- Reduced braking performance can require a greater distance to stop, increasing the risk of a crash.
- Is there a fix yet?
- Yes, and it is free. Dealers will install new software to disable the dynamic trailer braking calculations, free of charge. Owner notification letters are expected to be mailed November 27, 2026. Owners may contact Mack's customer service at 1-800-866-1177. Mack's number for this recall is SC0500. Vehicle Identification Numbers (VINs) involved in this recall will become searchable on NHTSA.gov on October 5, 2026.
- What should I do now?
- Check your own vehicle by its VIN with NHTSA, which is the record to act on. Mack calls this recall SC0500, which is the number on the owner letter and the dealer paperwork.
Answered from the register this site holds. NHTSA is the record to act on.
affected
in the notice
caught
| Campaign | 26V620 |
|---|---|
| Filed by | Mack Trucks, Inc. |
| System at fault | Service Brakes, Electric |
| Reported to NHTSA | 28 September 2026 |
| Model years | 2026-2027 |
| Vehicles named | MACK ANTHEM AN (4), MACK PIONEER PR (4) |
What the notice says today
The defect
Mack Trucks, Inc. (Mack) is recalling certain 2026-2027 Anthem AN (4) and Pioneer PR (4) vehicles equipped with a tanker application package. Inaccurate axle load calculations may cause reduced braking performance while transporting smoothbore tanker trailers.
The consequence
Reduced braking performance can require a greater distance to stop, increasing the risk of a crash.
The remedy
Dealers will install new software to disable the dynamic trailer braking calculations, free of charge. Owner notification letters are expected to be mailed November 27, 2026. Owners may contact Mack's customer service at 1-800-866-1177. Mack's number for this recall is SC0500. Vehicle Identification Numbers (VINs) involved in this recall will become searchable on NHTSA.gov on October 5, 2026.
What it said before
Nothing has changed while we have been watching. We first read this campaign on 1 October 2026 and last read it on 1 October 2026.
The copy we hold today hashes to c34a96b431096a9fdc420f545ed36ff0…, so if it is ever edited the change is provable rather than a matter of memory.
Last checked . No change has been recorded in the wording.
Official record: NHTSA campaign 26V620. Every Mack campaign we hold: Mack recalls.
Owners of these cars
No register publishes what happens after the letter. Owners do: tell us, in two taps.
Anonymous: no account, no cookie, nothing you type is stored beyond these choices. Figures appear once 3 owners have answered, and are published with the record under CC BY 4.0.