MileageCurve What breaks, and at what mileage

Lincoln Navigator 2003–2006

2nd generation · U228 · 459 complaints, 361 with mileage

Owners filed 459 complaints with NHTSA about the 2003–2006 Lincoln Navigator, and 361 of them record the mileage at which the failure happened. That is enough to show not just what fails, but when.

This generation has two distinct failure patterns rather than one, which is the most useful thing on this page. 24% of failures occur before 12,000 miles, which looks like a manufacturing defect, and a further 25% occur after 100,000, which looks like wear. Two different problems share one name in the complaint data — and an average of the two describes neither.

The most-reported areas are the suspension (20.0% of complaints, typically around 75,000 miles), the electrical system (10.0% of complaints, typically around 56,000 miles), the airbag system (8.5% of complaints, typically around 94,950 miles).

When failures happen

0–5k: 71 complaints (19.7%)0–5k5–10k: 12 complaints (3.3%)10–20k: 25 complaints (6.9%)10–20k20–30k: 10 complaints (2.8%)30–40k: 15 complaints (4.2%)30–40k40–50k: 21 complaints (5.8%)50–60k: 27 complaints (7.5%)50–60k60–70k: 24 complaints (6.6%)70–80k: 25 complaints (6.9%)70–80k80–90k: 18 complaints (5.0%)90–100k: 22 complaints (6.1%)90–100k100–120k: 31 complaints (8.6%)120–140k: 24 complaints (6.6%)120–140k140–160k: 16 complaints (4.4%)160–200k: 17 complaints (4.7%)160–200k200k+: 3 complaints (0.8%)710

10% of failures occur by 500 miles · a quarter by 13,000 · median 58,567 · three quarters by 100,000 · 90% by 135,000. Based on 361 complaints that record mileage.

What fails, and when

SystemComplaintsShareTypical mileageMiddle half
Suspension9220.0%75,00040,000–103,459
Electrical System4610.0%56,0009,003–100,000
Air Bags398.5%94,95055,714–124,890
Structure388.3%55,0003,000–95,000
Engine And Engine Cooling388.3%60,00032,000–99,000
Power Train296.3%30,0002,824–74,000
Visibility214.6%2,195350–30,000
Engine204.4%77,00060,000–120,400
Vehicle Speed Control194.1%56,85832,961–80,000
Service Brakes, Hydraulic163.5%15,0007,700–71,650

By model year

YearComplaintsWith mileage
2003179136
200411987
20057156
20069082

Which systems, and when

Complaints about this generation are not spread evenly across the vehicle, and the systems that generate the most of them do not all fail at the same point in a car's life. The median failure across all systems here is 58,567 miles; the figures below show which parts of the car run ahead of that and which run behind.

The suspension accounts for 20.0% of complaints (92 reports, 75 of them with a mileage figure), with a median of 75,000 miles, close to the vehicle's overall pattern. The middle half of these reports falls between 40,000 and 103,459 miles.

The electrical system accounts for 10.0% of complaints (46 reports, 30 of them with a mileage figure), with a median of 56,000 miles, close to the vehicle's overall pattern. The middle half of these reports falls between 9,003 and 100,000 miles.

The airbag system accounts for 8.5% of complaints (39 reports, 32 of them with a mileage figure), and it fails late — a median of 94,950 miles, considerably beyond the vehicle's overall median. That pattern is consistent with normal service life rather than a defect, though it matters for anyone buying an example already near that mileage. The middle half of these reports falls between 55,714 and 124,890 miles.

Body structure accounts for 8.3% of complaints (38 reports, 27 of them with a mileage figure), with a median of 55,000 miles, close to the vehicle's overall pattern. The middle half of these reports falls between 3,000 and 95,000 miles.

The engine and its cooling system accounts for 8.3% of complaints (38 reports, 33 of them with a mileage figure), with a median of 60,000 miles, close to the vehicle's overall pattern. The middle half of these reports falls between 32,000 and 99,000 miles.

The transmission and driveline accounts for 6.3% of complaints (29 reports, 24 of them with a mileage figure), and it fails early — a median of 30,000 miles, well before the vehicle's overall median. Failures clustered this far below the rest of the car usually point to a design or manufacturing problem rather than wear, because wear does not selectively target one system on low-mileage examples. The middle half of these reports falls between 2,824 and 74,000 miles.

Differences between model years

Within this generation, complaint volume is not constant across model years. The 2003 model year drew the most — 179 complaints — while 2005 drew the fewest at 71. The median year sits at 104.

The first year of the generation, 2003, sits above the median. That is a common pattern — early production of a redesigned vehicle tends to surface problems that later years do not repeat — and it is worth weighing when choosing between years.

Recalls and what they cover

No recall campaigns covering this generation appear in NHTSA's post-2010 recall file. That is not the same as an absence of problems — recalls address safety defects specifically, and many of the complaints above concern faults that are expensive or annoying without meeting that threshold.

Reported severity

Of the 459 complaints filed against this generation, 28 reported a crash; 17 reported a fire; 40 reported an injury; 1 reported a fatality. Crash-involved reports represent 6.1% of the total.

These are owner-reported outcomes, not verified investigations, and they are not adjusted for how many of these vehicles are on the road. They are included because the distinction between a fault that strands a car and a fault that causes a collision is the one that matters most, and it is not visible in a complaint count alone.

What this means if you are buying one

For a buyer, the two-peak pattern is the useful part. The early cluster — 24% of failures below 12,000 miles — will already have happened on any example you are looking at today, and either been repaired under warranty or not. Ask what was done. The late cluster, 25% above 100,000 miles, is the one still ahead of you if the car has lower mileage than that.

On inspection, the suspension and the electrical system are where this generation's reports concentrate, so those are the areas worth a specific look. The electrical system in particular shows a median failure mileage of 56,000, which gives a concrete number to compare against the odometer of any car you are considering.

None of this is a substitute for a pre-purchase inspection on the individual car. Aggregate patterns describe a population; the example in front of you has its own history.

Documented problems

Air suspension 2003-2006

Air spring leaks, compressor failure and height-sensor faults continue; complaint volume is highest around MY2004.

Spark plugs (5.4L 3-valve) 2005-2006

The 3-valve Triton used a two-piece spark plug whose lower porcelain/shell section seizes in the head and breaks off during removal, turning a routine plug change into head-removal-level work.

Variable cam timing / timing chain (5.4L 3-valve) 2005-2006

Cam phaser rattle at cold start and under light load, and timing chain tensioner/guide wear, on the 3-valve 5.4L; aggravated by low or degraded oil.

What owners reported

2003 · 1 miles · Visibility
I PURCHASED MY VEHICLE BRAND NEW IN JANUARY OF 2003. I HAVE HAD NUMEROUS PROBLEMS WITH THE VEHICLE SINCE DAY 1.THE ENTIRE COMPUTER HAD TO BE CHANGED. THE TRUCK STALLED ON ME AT HIGHWAY SPEED. IT TOOK OVER 2 1/2 WEEKS TO GET MY VEHICLE BACK.HERE IS A LIST OF THE OTHER PROBLEMS I HAVE HAD. THE REAR VENT MOTORS HAVE BEEN CHANGED . I HAD MY WINDOWS STUCK OPEN WITH HALF OF MY ELECTICAL SYSTEM OUT FOR O…
2003 · 1 miles · Visibility
I PURCHASED MY VEHICLE BRAND NEW IN JANUARY OF 2003. I HAVE HAD NUMEROUS PROBLEMS WITH THE VEHICLE SINCE DAY 1.THE ENTIRE COMPUTER HAD TO BE CHANGED. THE TRUCK STALLED ON ME AT HIGHWAY SPEED. IT TOOK OVER 2 1/2 WEEKS TO GET MY VEHICLE BACK.HERE IS A LIST OF THE OTHER PROBLEMS I HAVE HAD. THE REAR VENT MOTORS HAVE BEEN CHANGED . I HAD MY WINDOWS STUCK OPEN WITH HALF OF MY ELECTICAL SYSTEM OUT FOR O…
2003 · 1 miles · Wheels
I PURCHASED MY VEHICLE BRAND NEW IN JANUARY OF 2003. I HAVE HAD NUMEROUS PROBLEMS WITH THE VEHICLE SINCE DAY 1.THE ENTIRE COMPUTER HAD TO BE CHANGED. THE TRUCK STALLED ON ME AT HIGHWAY SPEED. IT TOOK OVER 2 1/2 WEEKS TO GET MY VEHICLE BACK.HERE IS A LIST OF THE OTHER PROBLEMS I HAVE HAD. THE REAR VENT MOTORS HAVE BEEN CHANGED . I HAD MY WINDOWS STUCK OPEN WITH HALF OF MY ELECTICAL SYSTEM OUT FOR O…
2003 · 1 miles · Electrical System
I PURCHASED MY VEHICLE BRAND NEW IN JANUARY OF 2003. I HAVE HAD NUMEROUS PROBLEMS WITH THE VEHICLE SINCE DAY 1.THE ENTIRE COMPUTER HAD TO BE CHANGED. THE TRUCK STALLED ON ME AT HIGHWAY SPEED. IT TOOK OVER 2 1/2 WEEKS TO GET MY VEHICLE BACK.HERE IS A LIST OF THE OTHER PROBLEMS I HAVE HAD. THE REAR VENT MOTORS HAVE BEEN CHANGED . I HAD MY WINDOWS STUCK OPEN WITH HALF OF MY ELECTICAL SYSTEM OUT FOR O…

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