2000 Toyota 4RUNNER Problems

What owners report

Owners of this model year most often report rust in the frame and underbody, frequently found during inspections, exhaust work or routine service, and often described as rusting from the inside out with little visible exterior corrosion. Complaints also cover rust-weakened suspension and control-arm attachment points, rear axle housings that seep fluid through corroded metal, and occasional starting, fuel gauge and electrical faults.

1. 1
   Body and structure

   Frame rust and rot (holes and cracks in frame rails)

   • 299 complaints (62%)
   • median 146,000 mi at 15.5 yrs old (235 state mileage)
   • 4 mention a crash, fire or injury
   • owner-quoted repair $2,700 (median of 10 quotes)
   • filed 2002–2023

   Owners describe frame rails with holes, cracks and large sections of missing steel, often found by a mechanic during unrelated work such as exhaust or oil service. Several say the frame rusted from the inside out while the body looked clean, and that dealers or shops told them the vehicle was not safe to drive; some report quotes for a replacement frame in the thousands of dollars. Owners frequently note that Toyota declined assistance, citing no recall for this model. Reported across the sample mostly between about 65,000 and 300,000 miles, often in vehicles used where road salt is applied.

   What to check: Have an independent shop inspect the inside and top of the frame rails, especially around the rear axle and above the gas tank; surface rust on the body tells you little. Ask whether the frame has ever been welded or patched.

   2 excerpts from owner complaints in NHTSA records

   “Like so many others I've heard of, the frame has rusted through. The back left wheel assembly is now wedged up onto the floorboards. The exhaust system has broken apart before the muffler. I just bought this car two years ago and loved it, but now am horribly disappointed in the frame and Toyota's lack of desire to do a recall.”

   NHTSA complaint #10891565, filed 2016-07, 130,000 miles

   “My 2000 4RUNNER has extensive frame rust. It has failed pa state inspections two different years. The first failure was in 2011 and was welded to pass. The second failure was 2013 and was again welded to pass. I fear the frame will beyond welding very soon. The rear differential has also began leaking to due excessive rust.”

   NHTSA complaint #10538177, filed 2013-08, 184,000 miles
2. 2
   Suspension

   Rear suspension mounts and brackets separating from frame

   • 82 complaints (17%)
   • median 170,000 mi at 16.1 yrs old (68 state mileage)
   • 3 mention a crash, fire or injury
   • filed 2003–2022

   Complaints describe the rear upper or lower control arm brackets and track bar mounts rotting through and breaking away from the frame, sometimes while driving at highway speed, which produces sudden swaying or loss of control. Owners say mechanics found the brackets cracked or half-disconnected where they weld to the frame, with the exhaust and rear axle affected as well. Some report the vehicle could not be repaired economically. Usually reported on high-mileage vehicles, commonly between roughly 100,000 and 230,000 miles, often after a rust inspection.

   What to check: Ask a mechanic to check the control arm and track bar brackets where they attach to the frame, not just the frame rails; look for cracks, separation or heavy flaking around the welds.

   2 excerpts from owner complaints in NHTSA records

   “While driving today the steering became unstable, erratic, and the car lurched out of my lane into oncoming traffic. A new noise appeared to be coming from rear left tire. When I safely pulled over and inspected vehicle I noted the frame was severely rusted and that the forward welded mount for the lower suspension arm had fractured along the factory weld and was dangling down. This car has never been wrecked. It has been inspected and passed pa state inspections yearly since 2002.”

   NHTSA complaint #10584522, filed 2014-04, 226,622 miles

   “I was driving 65 MPH on the interstate when I heard a clanking sound from the rear, the car started to sway terribly and shake and I lost control. I crossed over the highway lanes, rolled a couple of times and ended up in the ditch with the car upside down. A witness driving behind me said the wheel of the car fell off while I was driving. After inspecting the car, we saw the tire's tread had been ripped off, there were gashes in the tire, and the rear left control arm had fallen off. …”

   NHTSA complaint #11166571, filed 2019-01, 118,000 miles
3. 3
   Other or unknown

   Rear axle housing rust and fluid seepage

   • 72 complaints (15%)
   • median 138,000 mi at 13.3 yrs old (59 state mileage)
   • 6 mention a crash, fire or injury
   • owner-quoted repair $2,000 (median of 5 quotes)
   • filed 2001–2022

   Owners report gear oil weeping through the rear differential cover or housing itself rather than at a seal, leaving fluid on the spare tire, bumper and driveway. Complaints say the cover is welded to the axle, so repair meant replacing the whole rear axle assembly at significant cost, and that dealers attributed the seepage to porous, corroded metal. Reported from around 78,000 to 185,000 miles in the sample, generally on older vehicles in rust-prone areas.

   What to check: Look for oil staining on the rear axle cover, spare tire and bumper, and check the differential fluid level; ask whether the axle or cover has been replaced.

   2 excerpts from owner complaints in NHTSA records

   “No injury or crash . . . Reporting what I believe may be a design defect which could potentially be a safety danger. --- the rear differential housing in the 2000 Toyota 4RUNNER I own seems to be rusting unusually quickly. This is a 10-year old vehicle, but it only has 113,715 miles on the odometer when it sustained a leak due to corrosion. Apparently this is a known issue as both the local Toyota dealer and my local mechanic said they are seeing this issue with toyotas. …”

   NHTSA complaint #10334244, filed 2010-06, 113,715 miles

   “Rear differential cover is rusted and fluid leaches right through the metal spraying fluid on to spare wheel and rear bumper and anything in tow. Cover is evidentially cheap metal and is poorly designed as the cover is welded on and cannot be replaced without replacing the entire rear axle. There is no other significant rust on this vehicle and the remainder of the axle is in very good condition therefore I believe that this is a manufacturer defect which should be addressed by Toyota. …”

   NHTSA complaint #10345662, filed 2010-07, 150,000 miles

Buying note. The frame is the deciding factor on this model year: have it inspected inside and out, including the suspension brackets, before buying, and price in the possibility of frame repair or replacement. The rest of the vehicle is often reported to be in good condition, so a clean, well-checked frame is worth paying for.

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.