On certain trucks equipped with a saf holland simplex fifth wheel, the lever arm pivot bolt may have been over tightened. An over tightened pivot bolt can distort the pivot bolt spacer sleeve, which may prevent the fifth wheel latch jaw from closing and...
2002-2008 · 7 model years
Mack CHN Problems by year
Owners have filed 1 complaints about the Mack CHN across 7 model years, and it has 22 recalls. The 2007 has the most complaints once its age is allowed for (1). The most reported problem area is the engine & cooling.
- Complaints
- 1
- Recalls
- 22
- Crashes
- 0
- Fires
- 0
- Injuries
- 0
- Deaths
- 0
CHN complaints by model year
Highlighted: the year with the most complaints for its age. Older vehicles have had more time to collect complaints - the Safety Index grade allows for that.
Most common CHN problems
Mack CHN recalls 22
On certain trucks equipped with aset ac model engines, the engine as configured with an external exhaust gas recirculation system makes servicing the fuel injection lines difficult when using traditional tools. Therefore, it is possible for fuel leaks to...
On certain trucks equipped with parker single check valves (scv) provided by bendix. The defect exists in the parker scv that connects with the supply port of the sr-7 spring brake modulating valve. After prolonged use of the parker scv, the valve body...
On certain trucks equipped with bendix sr-7 spring brake modulating valves, the internal rubber check valve may leak causing a delay in the application of the spring brakes to park the vehicle after the operator pulls the dash valve button.
Certain trucks were recalled for the installation of sleeves on the fuel injection line as required by safety recall sc0317 (nhtsa recall no. 06V392). There is a possibility that the new sleeves may chafe the fuel injection line.
On certain trucks, the axle housings may have been manufactured with steel that was out of specification which could result in a fatigue failure over time.
On certain trucks, the nut that retains the steering wheel may not have been installed.
On certain trucks, a leak in the aset ac fuel injection line may spray fuel on the exhaust gas recirculation pipes that carry hot exhaust gases .
On certain trucks, the brake cam tubes on the steer and drive axles may not have been greased.
On certain trucks, the fuel line crossover bracket may prematurely fail and unexpectedly fall to the road. The location and size of the bracket draws a concern to the bracket being picked up and thrown by the drive axle wheels.
On certain trucks equipped with a legris air manifold, the brass push-to-connect cartridge may unexpectedly separate from the plastic housing.
On certain trucks equipped with sr-7 bendix brake valves, the check valve inside the valve cavity may not properly set, causing internal air leakage. If the check valve does not properly seat, the resulting leakage can cause a delay in the application of the...
Latest CHN complaints
2007 Mack truck chn 613, 427 aset ac engine failure due to oil pump drive gear spinning loose on auxiliary shaft. When the vehicle began traveling down hill, the oil pump drive gear failed causing an immediate loss of oil pressure. The engine became a critical instrument in controlling the vehicle's down hill speed particularly the engine brake feature aka the "jake brake". The engine brake uses engine oil flow to operate. Since there was no more oil flow, the engine brake was rendered unusable. At this point,...
Read the full complaint
the choice was to continue down hill and rely solely on the vehicle brakes to control the vehicle speed, or continue to use the engine without the added braking power of the engine brake knowing that the engine would be destroyed. The driver chose to destroy the engine and not risk his life or the lives of others. The dealer refused to repair the vehicle under warranty because the eecm indicated the engine's maximum allowed speed was exceeded. Further investigation revealed the problem is inherent to all aset engines because the oil pump gear helix was changed for the new design engine. The auxiliary shaft direction of rotation was reversed and the direction of thrust on the drive gear forces the drive gear away from the rear bearing journal which it is nested against. Older engine design had the direction of thrust toward the bearing journal which held the gear in place. Any condition, (like an engine overspeed) that would increase oil pressure could dislodge the gear. According to the dealer, an engine overspeed condition can only occur while going down hill and using the engine to control vehicle speed. If the hill would have been higher, the engine may not have been able to continue to slow the vehicle and a crash would most likely have occurred. This happened in southeast louisiana where high hills are non existent. Had this happened in a mountainous area, it could have been disastrous. Mack trucks refuses to discuss this any further. *Tr
Questions about the Mack CHN
Which Mack CHN years have the most problems?
By the number of complaints owners filed with NHTSA: 2007 (1). Allowing for how long each has been on the road, the 2007 stands out most. Complaint counts also rise with sales, so compare years of the same model rather than different models.
Which Mack CHN years have the fewest complaints?
What are the most common Mack CHN problems?
Across every model year, owners report problems with the engine & cooling (1) most often.
How many recalls does the Mack CHN have?
NHTSA lists 22 recalls across all Mack CHN model years. Each year's page lists the recalls for that year; check your own vehicle by VIN at nhtsa.gov/recalls to see whether the repair has been done.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) complaints and recalls, checked daily. Complaints are owners' own reports and are not verified. How we use the data