2018 Harley-Davidson Flhr Engine Problems
- Complaints
- 2about this part
- Share
- 40%of 5 total for the year
- Median mileage
- 100miles
- Trend
- Not enough dataFewer than 15 complaints, too few for a reliable trend.
NHTSA recorded 2 complaints about the engine of the 2018 Harley-Davidson Flhr, 40% of the 5 complaints for this model year. Where a mileage was given, the median is 100 miles.
Fewer than 15 complaints name this part, so treat the figures as a rough indication only.
Example complaints
Selected from NHTSA records; personal details are removed. They are consumer reports, not findings.
“Engine gets hot and stalls out in traffic due to engine case filling with oil, harley calls this wet sumping, hundreds of bike engines are blowing up all over the world, its all over the internet, with harleys new m8 engine, the bike stalls out with no warning, ive had cars and trucks almost run me over.”
NHTSA complaint #11097743, filed 2018-05, 100 miles“I have oil in my breather which is a result from engine sumping problems, I have had Harley Davidson to check recalls and there were none., the bike has 22853 miles on it. Also Harley Davidson checked maintenance records to see if my oil pump had been replaced, they said it had not. The sumping problems could cause a catastrophic failure and an accident”
NHTSA complaint #11749847, filed 2026-07Related service bulletins
- 11037861Sep 17, 2026SERVICE BULLETIN M1490 (V 26.9.4): DIGITAL TECHNICIAN II - UPDATES AND RELEASE NOTES. PURPOSE: Revision. This bulletin informs dealers that Harley-Davidson has made a software…
- 11036578Aug 14, 2026SERVICE BULLETIN M1733: COSMETIC CYLINDER STAINING (ALL MILWAUKEE-EIGHT MODELS). PURPOSE: Initial release. This bulletin informs dealers that cosmetic staining or etching on the…
- 11035941Jul 25, 2026SERVICE BULLETIN M1490 (V 26.8.3): DIGITAL TECHNICIAN II - UPDATES AND RELEASE NOTES. PURPOSE: Revision. This bulletin informs dealers that Harley-Davidson has made a software…
- 11034748Jun 11, 2026SERVICE BULLETIN M1490 (V 26.7.3): DIGITAL TECHNICIAN II - UPDATES AND RELEASE NOTES. PURPOSE: Revision. This bulletin informs dealers that Harley-Davidson has made a software…
- 11032452Apr 24, 2026SERVICE BULLETIN M1490 (V 26.6.2): DIGITAL TECHNICIAN II - UPDATES AND RELEASE NOTES. PURPOSE: Revision. This bulletin informs dealers that Harley-Davidson has made a software…
- 11031147Mar 31, 2026SERVICE BULLETIN M1490 (V 26.5.2): DIGITAL TECHNICIAN II - UPDATES AND RELEASE NOTES. PURPOSE: Revision. This bulletin informs dealers that Harley-Davidson has made a software…
- 11031167Mar 14, 2026SERVICE BULLETIN M1679: AFTERMARKET EXHAUST HEADER DEBRIS. PURPOSE: Initial release. This bulletin informs dealers that Harley-Davidson has identified instances of premature…
- 11028618Jan 28, 2026SERVICE BULLETIN M1713 (REV B): DTII UPDATE PROCEDURE FOR SOFTWARE VERSION (26.3.2). PURPOSE: Revision B. This bulletin informs dealers that an issue was discovered in the…
- 11028615Jan 28, 2026SERVICE BULLETIN M1490 (V 26.3.2): DIGITAL TECHNICIAN II - UPDATES AND RELEASE NOTES. PURPOSE: Revision. This bulletin informs dealers that Harley-Davidson has made a software…
- 11016842Mar 29, 2025GENUINE MOTOR PARTS AND MOTOR ACCESSORIES BULLETIN PAB1165 (REV A): H-D SYN3 SAE 15W50 / SAE 50 AVAILABILITY. PURPOSE: Revision (A) * Updated: Summary, Update table. This…
Engine: other model years
Other parts of the 2018 Harley-Davidson Flhr
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About this data. Data from NHTSA (ODI) complaints, recalls, TSBs and investigations, updated Oct 28, 2026. Complaints are unverified consumer reports and may be duplicated or inaccurate.
To check a specific vehicle for open recalls, use its VIN at nhtsa.gov/recalls. Methodology