Oil leak on the 2001 Toyota 4RUNNER
Only 4 reports for this mode came with an odometer reading, which is too few for percentiles to mean anything. The page is here because someone linked to it; treat the figures as anecdotes, and see the full report for this year instead.
When oil leak gets reported
There are 5 reports of oil leak on the 2001 Toyota 4RUNNER, 4 with a mileage attached. That is too few to place the failure on the odometer with any confidence.
A part like this is normally expected to survive 95,000 miles. It is the 8th most-reported problem on this model year.
The whole distribution
| 10th | 25th | Median | 75th | 90th |
|---|---|---|---|---|
| — | — | 125,000 miles | — | — |
Read the 10th percentile as “one report in ten arrived this early”. Exact figures are shown in this table because it is the table of record; everywhere else on the site they are rounded to the precision the sample can carry.
What a percentile can and cannot tell you here
These five numbers describe the readings owners gave, in order. The median is the middle one: half the reports arrived below it. The 10th and 90th are the edges of the bulk of the distribution, and the distance between them is the part worth reading. A tight spread — say 70,000 to 95,000 miles — points at something that wears out on a schedule, and the schedule is knowable. A wide one, 20,000 to 190,000, points at a fault that hits some cars and never troubles others, which means the mileage on the listing in front of you tells you very little about your odds.
What these figures are not is a survival curve. Every reading here comes from a car whose owner filed a complaint, so the sample contains only failures: it cannot say what share of the fleet made it past 150,000 miles untouched, because those owners had nothing to report. Nor is the mileage the moment of failure — it is the odometer reading as recalled at the time of filing, which may be weeks later and is sometimes rounded to the nearest ten thousand by the person typing it.
Percentiles are shown at all only once 8 readings exist for the vehicle and mode. Below that the middle of a handful of numbers is noise wearing a decimal point, so the figures are withheld rather than dressed up.
What happens, and what it costs
Putting it right typically runs $250–$2,200 at an independent US shop. That range is an editorial estimate held in this site's failure-mode catalogue, not a figure from NHTSA, and it is a repair cost rather than a diagnosis cost.
The same failure on other years
The same failure is reported on 5 model years of this car. It shows up earliest on the 2015, at a median of 20,000 miles, and latest on the 2000 at 180,000 miles.
By volume the 2000 carries the most reports, with 5; the 2001 has 5. A mode that appears across most years of a model is usually a design choice rather than a bad batch.
If one year stands out to the left, that is the year to avoid; if the whole line sits at a similar mileage, this is wear rather than a defect in one production run.
Tick median reported mileage Solid middle half of reports Faint 10th to 90th percentile Colour how bad the failure is when it happens
What owners wrote
Verbatim from NHTSA complaint narratives, trimmed for length. The mileage is the one the owner gave.
The rear differential is rusting through to the point of leaking oil. I suspect the differential is corroded to the point where is mechanically unsound and could cause a catastrophic failure if hit by a rigid obstacle in the roadway. *tr
3rd generation 2001 toyota 4runner with excessive frame and body rust. The gas tank stem is rusted, the rear differential is literally porous and leaking oil due to excessive rust. Rear bumper is rusted, spare tire mount is rusted. Other areas of rust are too numerous to list. Repair shop said car is not worth fixing. Dana corp that made frames for toyota tacomas/tundras that were recalled also is best know for rear differentials. Why weren't the 4runners included in the recall/buyback by toyota? *tr
3rd generation 2001 toyota 4runner with excessive frame and body rust. The gas tank stem is rusted, the rear differential is literally porous and leaking oil due to excessive rust. Rear bumper is rusted, spare tire mount is rusted. Other areas of rust are too numerous to list. Repair shop said car is not worth fixing. Dana corp that made frames for toyota tacomas/tundras that were recalled also is best know for rear differentials. Why weren't the 4runners included in the recall/buyback by toyota? *tr
Also reported on the 2001 Toyota 4RUNNER
Other body or interior problem
Differential or transfer case failure
Rust or structural corrosion
Control arm, ball joint or bushing failure
Other suspension problem
Other engine problem
How far this goes
This page is kept out of search results because 5 reports is not enough to publish percentiles from. It stays reachable because somebody looking at this exact car would rather see the reports than be told there are none.
Complaints are voluntary, so 5 is a floor and not a count of affected cars. Mileages are typed in by owners and cluster on round numbers. And the mode itself is assigned by software reading the complaint text, which is reliable in bulk and fallible one report at a time.
Questions this page answers
At what mileage does oil leak happen on the 2001 Toyota 4RUNNER?
Across 4 owner reports that included an odometer reading, half were filed by 125,000 miles. A quarter were filed before — and a quarter after —. These are the mileages owners reported when they complained, not a prediction for any individual car.
How common is oil leak on the 2001 Toyota 4RUNNER?
5 reports have been filed with NHTSA, about 0.1 per 1,000 vehicles. Complaints are voluntary, so this is a floor rather than a count of affected cars.
What this is and is not. These are the mileages at which owners chose to complain to a federal agency, which is not the same as the mileage at which the part fails on every car. It skews toward failures that happened outside warranty, cost real money, or frightened someone. It is still the only public dataset that carries failure mileage at all, and the shape of a few hundred readings is informative even when a single one is not. Methodology · JSON · this failure on other cars
Source Owner complaints and recall records published by the US National Highway Traffic Safety Administration, model years 1996–2027 Figures rebuilt Published by AtWhatMileage How every figure is computed