MileageCurve What breaks, and at what mileage

Ford Expedition 1997–2002

1st generation · UN93 (derived from the PN96 F-150) · 5,514 complaints, 2,507 with mileage

Owners filed 5,514 complaints with NHTSA about the 1997–2002 Ford Expedition, and 2,507 of them record the mileage at which the failure happened. That is enough to show not just what fails, but when.

50% of failures occur beyond 100,000 miles — a wear pattern. The car generally reaches substantial mileage before trouble starts.

The most-reported areas are the engine and its cooling system (14.7% of complaints, typically around 104,000 miles), the electrical system (13.3% of complaints, typically around 97,000 miles), the tyres (9.9% of complaints, typically around 62,000 miles).

When failures happen

0–5k: 29 complaints (1.2%)0–5k5–10k: 12 complaints (0.5%)10–20k: 35 complaints (1.4%)10–20k20–30k: 67 complaints (2.7%)30–40k: 118 complaints (4.7%)30–40k40–50k: 120 complaints (4.8%)50–60k: 127 complaints (5.1%)50–60k60–70k: 204 complaints (8.1%)70–80k: 181 complaints (7.2%)70–80k80–90k: 187 complaints (7.5%)90–100k: 184 complaints (7.3%)90–100k100–120k: 377 complaints (15.0%)120–140k: 295 complaints (11.8%)120–140k140–160k: 219 complaints (8.7%)160–200k: 223 complaints (8.9%)160–200k200k+: 129 complaints (5.1%)3770

10% of failures occur by 39,000 miles · a quarter by 65,000 · median 99,000 · three quarters by 133,334 · 90% by 173,883. Based on 2,507 complaints that record mileage.

What fails, and when

SystemComplaintsShareTypical mileageMiddle half
Engine And Engine Cooling81114.7%104,00076,000–132,000
Electrical System73413.3%97,00066,000–129,000
Tires5459.9%62,00033,000–102,000
Vehicle Speed Control5049.1%109,00072,000–140,000
Suspension4508.2%99,97565,000–134,000
Visibility3676.7%70,00048,000–98,000
Power Train3296.0%85,00048,000–130,000
Service Brakes, Hydraulic2534.6%80,00052,400–116,000
Steering2344.2%91,20059,500–134,000
Structure1733.1%90,00060,665–130,000

By model year

YearComplaintsWith mileage
19971,065291
19981,022366
19991,137466
20001,136574
2001739492
2002415318

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 99,000 miles; the figures below show which parts of the car run ahead of that and which run behind.

The engine and its cooling system accounts for 14.7% of complaints (811 reports, 555 of them with a mileage figure), with a median of 104,000 miles, close to the vehicle's overall pattern. The middle half of these reports falls between 76,000 and 132,000 miles.

The electrical system accounts for 13.3% of complaints (734 reports, 483 of them with a mileage figure), with a median of 97,000 miles, close to the vehicle's overall pattern. The middle half of these reports falls between 66,000 and 129,000 miles.

The tyres account for 9.9% of complaints (545 reports, 93 of them with a mileage figure), and they fail early — a median of 62,000 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 33,000 and 102,000 miles.

Throttle and speed control accounts for 9.1% of complaints (504 reports, 257 of them with a mileage figure), with a median of 109,000 miles, close to the vehicle's overall pattern. The middle half of these reports falls between 72,000 and 140,000 miles.

The suspension accounts for 8.2% of complaints (450 reports, 126 of them with a mileage figure), with a median of 99,975 miles, close to the vehicle's overall pattern. The middle half of these reports falls between 65,000 and 134,000 miles.

Visibility equipment accounts for 6.7% of complaints (367 reports, 131 of them with a mileage figure), with a median of 70,000 miles, close to the vehicle's overall pattern. The middle half of these reports falls between 48,000 and 98,000 miles.

Differences between model years

Within this generation, complaint volume is not constant across model years. The 1999 model year drew the most — 1,137 complaints — while 2002 drew the fewest at 415. The median year sits at 1,043.

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 5,514 complaints filed against this generation, 332 reported a crash; 679 reported a fire; 350 reported an injury; 44 reported a fatality. Crash-involved reports represent 6.0% 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, a late-failure pattern shifts the question from whether to when. 50% of reported failures occur beyond 100,000 miles, so an example approaching that figure is approaching the range where other owners started reporting problems. The middle half of all failures falls between 65,000 and 133,334 miles.

On inspection, the engine and its cooling system 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 97,000, 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

Engine 1997-2002

Two-valve Triton spark plug ejection. The aluminum cylinder head carries only about four threads of engagement; plugs work loose under cylinder pressure and blow out, stripping the head threads and requiring insert repair or head replacement.

Cruise control / electrical 1997-2002

Texas Instruments speed control deactivation switch mounted on the master cylinder leaks brake fluid onto energized contacts, overheats and ignites — fires occur with the engine off and key out. Covered by Ford's large speed-control switch recall campaigns (05V-388 and successors).

Suspension

Rear air suspension air spring and compressor leaks causing rear-end sag and compressor burnout.

What owners reported

1997 · 5,000 miles · Latches/Locks/Linkages
TL*- THE CONTACT STATED THAT THE 1997 FORD EXPEDITION XLT HAD A NUMBER OF PROBLEMS WITH THE CHILD SAFETY LOCKS. WHEN HE PUT SOMEONE IN THE BACK SEAT THE SAFETY LOCKS ENGAGED AND THE PASSENGER COULD NOT OPEN THE DOOR. THE CONTACT SPOKE TO THE DEALERSHIP, AND STATED THAT THEY HE SHOULD HAVE THE LOCKS REPLACED AT HIS OWN COST. THE CONTACT FELT THIS WAS SAFETY PROBLEM, IF A CRASH OCCURRED THE BAC…
1997 · 15,000 miles · Service Brakes, Air
ABS BRAKES: BRAKES ON '97 FORD EXPIDITION OFTEN FAILED DUE TO MALFUNCTIONING ABS BRAKES. PEDAL BECOMES JERKY AND WILL NOT GO DOWN. CLUNKING NOISE FROM FRONT. DOES NOT HAPPEN CONSISTANTLY. I HAVE TO APPROACH VERY CAUTIOUSLY TO AVOID COLLOSIONS. EVERY OTHER OWNER I HAVE TALKED TO HAS SAME COMPLAINT, YET FORD HAS NO KNOWLEDGE OF IT. FRONT BREAKS HAVE BEEN REDONE, STILL HAPPENS. HAS DONE IT SINCE NEW…
1997 · 29,000 miles · Vehicle Speed Control
TL*THE CONTACT OWNS A 1997 FORD EXPEDITION. THE CONTACT STATED THAT THERE WAS A DEFECT RECALL ON THE CRUISE CONTROL UNIT IN HIS VEHICLE. THE VEHICLE WAS TAKEN TO AN AUTHORIZED DEALER TO BE SERVICED FOR THE RECALL REPAIR. AFTER THE REPAIR WORK WAS PERFORMED, THE CRUISE CONTROL DEVICE DID NOT OPERATE. THE CONTACT STATED THAT THE CRUISE CONTROL WAS OPERATING NORMALLY PRIOR TO THE REPAIR. THE AUT…
1997 · 32,879 miles · Service Brakes, Hydraulic
THE CAR IS A 1997 FORD EXPEDITION. THE FRONT TO REAR BRAKE LINE CORRODED AND FAILED. THIS HAPPENED COASTING INTO MY DRIVEWAY. EVEN THOUGH IT IS A SPLIT SYSTEM THE BRAKING LEFT WAS MINIMAL. THE PARTITION BETWEEN THE FRONT CHAMBER AND THE BACK DIDN'T SEEM TO LEAVE ENOUGH FLUID IN THE FRONT CHAMBER TO ALLOW EFFECTIVE REMAINING BRAKING. NOT TO MENTION THE BRAKE LINE CORRODING THROUGH IN LESS THAN…

Other generations