Mack preliminary evaluation PE20005
mDrive Transmission Failure to Disengage. NHTSA’s Office of Defects Investigation opened this preliminary evaluation about the manual transmission on 29 model years (2013–2016). Opened Apr 28, 2020, closed Apr 4, 2022 after 1.9 years without a recall. closed
What NHTSA says
Source: Office of Defects Investigation, as filedOn April 28, 2020, the Office of Defects Investigation (ODI) opened PE20-005 to investigate reports of 2013-2015 Mack CHU and CXU trucks equipped with mDrive transmissions continuing to push forward when stopping, possibly increasing the risk of a crash. After more field reports were discovered, the scope of the investigation was expanded to cover MY 2013-2016 vehicles. The mDrive transmission is Mack's version of Volvo's I-Shift transmission, an automated manual transmission that allows gear shifting without the use of a clutch pedal. Early I-Shift transmissions were recalled (13V-268) to address a missing redundant clutch disengagement switch that could prevent the clutch from automatically disengaging when the brake was applied. If a loss of signal from the brake air pressure switch occurred, the clutch would remain engaged while braking. Although Mack's mDrive transmission adopted the latest Volvo I-Shift design and was built with the redundant clutch switch, ODI received field reports alleging that the mDrive transmission would not disengage when coming to a stop like the Volvo I-Shift transmissions in recall 13V-268. After more than a year of information requests, data exchanges and grouping, and analyzing data, ODI was able to correlate two versions of transmission software (ID 23084009 and ID 23084004), with two frequently replaced parts ('solenoid valve' and 'cylinder assy clutch') as outliers. However, Mack dismissed the replacement parts as being normal service parts for worn clutch systems. According to Mack, unlike the I-Shift recall, loss of one or more of the switches would not keep the clutch engaged but might cause a delay in the clutch disengaging, possibly due to the software/control system settings, the worn parts and system reaction time. To demonstrate the possible switch failure outcomes, Mack outfitted a subject model truck with a panel that could disable each switch on command. During test drives at the Mack facility, the demonstrator truck stopped when the brake was applied each time, and the truck did not stall when the brake was applied, even when the clutch was engaged. Even though failure of one of the switches could delay clutch disengagement, the stopping distance would still be shorter than one of the recalled Volvo I-Shift transmission trucks. With this information, as well as a lack of known crash incidents related to this complaint, ODI concludes that the Mack vehicles do not present an unreasonable risk to motor vehicle safety. Although ODI is closing this PE, Mack/Volvo should continue improving the transmission control unit software to further refine the clutch disengagement strategy. The closing of this investigation does not constitute a finding by NHTSA that a safety-related defect does not exist. Claims are still being submitted and the Agency will continue to monitor the issue and reserves the right to take further action if warranted by new circumstances.
A Preliminary Evaluation is the first formal stage: NHTSA has decided the complaints and other information it screened are worth a closer look, and asks the manufacturer for its own data on the condition. The summary is the agency’s own text from its investigation file, unedited; the opening and closing resumes with the full reasoning are on NHTSA’s site under this number.
What this means for an owner
Source: and what happens nextAn investigation is not a finding that a defect exists, and it puts no duty on anyone. NHTSA opens a Preliminary Evaluation when complaints and other reports suggest a condition worth asking the manufacturer about; it upgrades to an Engineering Analysis when the answers warrant testing; it closes either when it recommends a recall, when the manufacturer recalls on its own, or when no defect trend is found. The agency’s own goals are about four months for a petition, eight for a Preliminary Evaluation or a Recall Query and eighteen for an Engineering Analysis; many run longer.
This one closed without a recall. That means NHTSA found no defect trend it chose to act on at the time, or the manufacturer addressed the condition another way (a service campaign or a bulletin, which have their own pages). A closed file can be reopened if new reports arrive.
Model years it names
Source: as NHTSA filed themAlso named: 2016 Mack Anthem; 2013 Mack CHU; 2014 Mack CHU; 2015 Mack CHU; 2016 Mack CHU; 2013 Mack CXU; 2014 Mack CXU; 2015 Mack CXU; 2016 Mack CXU; 2016 Mack GU; 2016 Mack Granite (gr); 2016 Mack Granite (gu); 2016 Mack LEU; 2016 Mack LR; 2016 Mack LR6; 2016 Mack MRU; 2013 Mack Pinnacle (chu); 2014 Mack Pinnacle (chu); 2015 Mack Pinnacle (chu); 2016 Mack Pinnacle (chu); 2013 Mack Pinnacle (cxu); 2014 Mack Pinnacle (cxu); 2015 Mack Pinnacle (cxu); 2016 Mack Pinnacle (cxu); 2016 Mack TD; 2016 Mack Terrapro (leu); 2016 Mack Terrapro (leu/mru); 2016 Mack Terrapro (mru); 2016 Mack Titan (td).
A vehicle page’s investigation list carries the same action; a name here is the scope NHTSA opened, not a list of affected VINs.
Common questions
Source: NHTSA Office of Defects InvestigationIs PE20005 a recall?
No. A preliminary evaluation is NHTSA asking questions, not a recall. A safety recall carries an NHTSA campaign number and a duty to repair for free; this one closed without one. Whether one particular vehicle has an open recall is a VIN question at nhtsa.gov/recalls.
Is PE20005 still open?
No. It closed on Apr 4, 2022 without a recall.
Which vehicles does PE20005 cover?
NHTSA opened it on 29 model years: 2016 Mack Anthem, 2013 Mack CHU, 2014 Mack CHU, 2015 Mack CHU, 2016 Mack CHU, 2013 Mack CXU and more. That is the scope of the inquiry, not a list of affected vehicles; a recall, if one follows, defines its own population by VIN.