- The problem
- In the event of turbocharger compressor wheel failure, one or more of the four capscrews that hold the turbocharger together may be struck by parts of the compressor wheel, resulting in the capscrews being damaged. If these capscrews are damaged to the point that they allow the compressor back plate to dislocate from the turbocharger bearing housing, engine lubricating oil may be allowed to escape under pressure, contacting the engine exhaust manifold sections or turbocharger turbine housing.
- The fix
- Dealer will install a shield for the heads of the four capscrews, along with stronger sae 8 grade 8 capscrews, if necessary, at no cost to owner.
Vehicle safety record
1979 Mack DM Problems, complaints & recalls
No owner complaints about the 1979 Mack DM have been filed with NHTSA. It is covered by 1 recall, the latest in May 1979 for the engine.
NHTSA data checked
BFewer problems than a typical DM year, for its age
- Complaints
- 0
- Recalls
- 1
- Crashes
- 0
- Fires
- 0
- Injuries
- 0
- Deaths
- 0
1979 Mack DM recalls 1
Recall repairs are free. Your dealer fixes them whether or not you bought the car there - check your VIN at nhtsa.gov/recalls to see if yours is done. What to do
What owners say
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No complaints about the 1979 Mack DM yet
No owner has filed a complaint about this vehicle with NHTSA. If yours has a problem, share it here and report it to NHTSA.
Mack DM: every year compared
All DM years1979 Mack DM vs rivals
| Vehicle | Complaints | Recalls | Grade | |
|---|---|---|---|---|
| 1979 Mack DM | 0 | 1 | B | |
| 1979 Mack Mack | 1 | 3 | D | Compare |
More sales usually means more complaints, so compare similar vehicles of the same year. The grade compares each vehicle with its own model's other years.
Questions about the 1979 Mack DM
Does the 1979 Mack DM have any recalls?
Yes - NHTSA lists 1 recall for the 1979 Mack DM: engine (May 1979). Recall repairs are free at any authorized dealer. Enter your VIN at nhtsa.gov/recalls to see whether yours has been fixed.
How many complaints has the 1979 Mack DM had?
None have been filed with NHTSA so far.
Is the 1979 Mack DM a reliable vehicle?
Its Safety Index is 74 out of 100 (grade B: fewer problems than a typical Mack DM year, for its age). The index weighs complaints, crashes, fires, injuries, deaths and recalls against how long the vehicle has been on the road, compared with the same model's other years. It is not a measure of every repair - read the complaints and owner experiences, and have any used vehicle inspected before you buy.
What should I do if my 1979 Mack DM has a problem?
If it is a safety problem, stop driving it if it is unsafe and contact your dealer. Report it to NHTSA at nhtsa.gov/report-a-safety-problem - enough reports start investigations and recalls - and share your experience here so other owners know what to look for.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) complaints and recalls, checked . Complaints are owners' own reports and are not verified. How we use the data