2002 Toyota 4RUNNER Problems

What owners report

Complaints about this model year center overwhelmingly on frame and underbody corrosion. Owners say the frame rail rusts from the inside out, with holes found near the rear cross member, rear control arm mounts, and around the muffler and trailer hitch area. Many describe otherwise well-kept, relatively low-mileage vehicles that failed state inspection or were judged unfit to drive once the corrosion was found; a smaller group reports the rear axle housing rusting through and leaking gear oil.

1. 1
   Body and structure

   Frame rust-through and perforation

   • 108 complaints (48%)
   • median 145,450 mi at 14.8 yrs old (79 state mileage)
   • 1 mention a crash, fire or injury
   • owner-quoted repair $2,800 (median of 5 quotes)
   • filed 2011–2023

   Owners describe holes rusted through the frame rails, often on the passenger side between the middle and rear cross members, and sometimes severe enough that a frame section or tailpipe separated. Several say the corrosion started inside the frame and was hidden by undercoating until the metal was gone. Complaints state that dealers and independent shops declared the vehicle unfit to drive or said it would fail the next inspection, and that Toyota declined assistance because the vehicle was outside warranty. Mostly reported between roughly 100,000 and 200,000 miles, and frequently on vehicles that spent years in road-salt states.

   What to check: Have the frame inspected on a lift, especially the rear rails, control arm mounts, and the area around the muffler; probing with a screwdriver through any bubbled coating will reveal soft metal. Ask where the vehicle was driven and whether the frame has been repaired, plated, or welded.

   2 excerpts from owner complaints in NHTSA records

   “Frame has rusted through to the point of being a danger to drive my vehicle. Frame did not easily appear rusted when I purchased my vehicle 4 years ago. It appears that the frame rusted from the inside out and the coating concealed the damage until it was too late to repair. My vehicle drives perfectly but is not safe due to the frame damage.”

   NHTSA complaint #11329213, filed 2020-06, 151,000 miles

   “I recently had my vehicle in for service and to get new tires. While on the lift, the mechanic pointed out to me that the frame on the passenger's side is beginning to rust through. This is an obvious potential safety issue and as I have researched possible repairs, it appears that this is a very common problem for this year and model. This should be recalled.”

   NHTSA complaint #11405965, filed 2021-04, 278,000 miles
2. 2
   Other or unknown

   Rear axle housing rusted through, gear oil leak

   • 36 complaints (16%)
   • median 132,000 mi at 12.9 yrs old (29 state mileage)
   • filed 2004–2019

   Owners report gear oil weeping from small rust holes in the rear axle housing, sometimes noticed first as a strong gear-oil smell or fluid on the rear of the vehicle. Because the housing has no separate cover, shops have described replacing the whole rear axle assembly rather than the damaged section; one owner was quoted roughly $3,000 and another reported a temporary grind-and-epoxy repair. Reported from as little as about 72,000 miles up to roughly 200,000 miles, again mostly on vehicles driven in road-salt areas.

   What to check: Look for oil weeping or staining on the rear axle housing and differential, check the gear oil level, and ask whether the axle assembly has been repaired or replaced.

   2 excerpts from owner complaints in NHTSA records

   “After noticing a strong gear oil odor and seeing the actual gear oil on the back the of the vehicle I was alarmed to find out that the rear axle housing had rust perforating the rear of the housing. Once the housing was checked by a certified mechanic and turned away due to fear of destroying the housing, I removed the vehicle from the road.”

   NHTSA complaint #10474018, filed 2012-09, 203,000 miles

   “My frame is rotting out. I just had to replace my rear axle because it had almost rotted through. It was actually weaping gear oil out of small holes through the rot. Some of the frame had to be welded to pass inspection.”

   NHTSA complaint #10777896, filed 2015-09, 136,000 miles
3. 3
   Brakes

   Brake pulsation, vibration, and rusted brake lines

   • 28 complaints (12%)
   • median 100,000 mi at 9.0 yrs old (23 state mileage)
   • 3 mention a crash, fire or injury
   • filed 2002–2020

   Owners describe a pulsing brake pedal and heavy vibration when braking, especially after long descents, with front rotors replaced at low mileage in some cases. Others report brake lines rusted through and failing suddenly, with one vehicle requiring both front and rear lines to be replaced. A separate complaint describes all warning lights coming on and the need for unusually hard pedal pressure, traced to the ABS unit. Reported from under 60,000 miles for rotor pulsation up to around 150,000 to 250,000 miles for rusted lines and ABS faults.

   4 related service bulletins

   What to check: Inspect the hard brake lines under the vehicle for rust and swelling, and test-drive at highway speed to check for pedal pulsing or vibration under braking.

   2 excerpts from owner complaints in NHTSA records

   “The entire frame and other parts of the underbody are rusted. The brakes both front and back were also rusted. I pulled off from the highway and stopped to pickup my dogs. When I tried to leave my brakes were gone. When the car was towed to my mechanic he said both front and rear brake lines were rusted through and had to be replaced. I could have been killed. He also said that the frame is rusted and is dangerous to drive. I am afraid to drive this car.”

   NHTSA complaint #10714231, filed 2015-05, 142,059 miles

   “The frame of this 4RUNNER has been experiencing excessive rust since the time I got it used from a dealer. Once their undercoating wore off, my mechanic replaced rusted up brake lines back about 9 years ago. He said it was because the frame was very rusty and they did a new rust treatment. For the past few years I have been battling issues related to the frame. A plate was put in to strengthen an area. It only has 164k on it, I rebuilt the transmission at 125k, and the body is in good shape. …”

   NHTSA complaint #11194759, filed 2019-04, 145,000 miles
4. 4
   Vehicle speed control

   Loss of power or stalling with VSC and traction control

   • 10 complaints (4%)
   • median 97,000 mi at 13.0 yrs old (10 state mileage)
   • 1 mention a crash, fire or injury
   • filed 2004–2026

   Owners describe the engine cutting power briefly, especially while turning or after stopping in snow, with the stability control or traction control system activating and warning lights on the dash. One account describes the vehicle bogging down when accelerating from a stop in winter conditions, and another reports loss of power with a VSC message and beeping. Reported at varying mileage, from very low mileage accounts to vehicles past 200,000 miles, often in snow or low-traction conditions.

   What to check: During the test drive, accelerate from a stop on a loose or wet surface and watch for dash warnings; ask whether any ABS, VSC, or traction control codes have been stored or repaired.

   2 excerpts from owner complaints in NHTSA records

   “4 wheel drive would not work. Vcs lites and check engine lites on. Car engine filled with black smoke and was towed to repair shop. Details: drove on freeway and lost traction and than on shoulder with above problem. Differential repaired. Two days later lites on again and oil leak.”

   NHTSA complaint #10629903, filed 2014-09, 142,986 miles

   “1) stopped at stop sign with snow on the ground. Then accelerate turning onto another road. 2) vehicle can accelerate and move a few feet before the trac (traction control) system activates. The power to the engine is then cut off. At this point you are unable to move, stuck in the middle of an intersection. There is a few second delay before you can get any power back to the engine. Ultimately, you are left in the middle of the intersection with no power to the wheels waiting to see if another vehicle is going to t-bone you. …”

   NHTSA complaint #10326072, filed 2010-04, 1 miles

Buying note. The frame and underbody corrosion reports are the main thing to weigh on this model year, so a lift inspection by someone familiar with these trucks is worth the cost before purchase. Mechanical faults such as ball joints and brakes are more routine, but service records showing recent work on those parts help.

Summary written with AI from a sample of 60 NHTSA complaints for this model year (picked at random, with complaints that state a mileage and recent ones taken first), then checked automatically against the source records. Where a problem shows a complaint count, every complaint for this model year was matched with fixed keyword rules (written with AI and tested against the sample), and the mileage, age and repair figures are calculated from those complaints; owners' figures are as stated, not verified. Other counts refer to the sample. The excerpts come from NHTSA's public complaint records and are unverified; capitalisation is normalised, NHTSA staff notes are removed, and shortened text ends with “…”. Something wrong? Request a correction.