Messing with odometers is a federal offense; where did you get the 40 percent figure? Plus every inspection you give actual odometer reads; less would show up.
The mileage myth aside, why on earth would anyone pay $23,000.00 dollars for a 2001 Nissan Maxima with 87,000 miles on it?! You got straight up had!
When checking a vehicle for purchase for a customer, I pull the true mileage from the computer, and approx 40% of the time it is higher than shown at the odometer.
There are different memories of traveled mileage. You cannot buy a scan tool on the open market to access 100% of vehicle computer (to fully unlock all access).
The best you can buy is 70% access to your vehicle's computer (Ford recently bumped access back to 50% on their cars, forcing people back into their service bays).
This is the same as... you cannot buy the books to locate the minimum of 10 hidden spots (codes) on your vehicle to verify your VIN #.
People do not want to pay for leased KMs and drop the kms back before each emissions test or service, and before returning the vehicle to the dealer at the end of the lease.
Anytime mileage may be recorded.
The most popular way to give a lower reading is to set the gear ratio reading into the computer incorrectly to produce a 1/2 speed reading. This gives you a 40 km reading when you are doing 80kms and results in a true traveled 80KM car, reading 40 kms on the odometer.
I had Nissan Maxima 2001 SE. I was very very frustrated with this car, and now I don't know what to do with this piece of junk.
Ended up spending money for repairs one after the other.
Never ever go with Nissan, it's very expensive to service them.
Unfortunately this reviewer is correct, 2001 Maxima's tend to have numerous engine issues: P0505 code (IACV and ECU - repair cost about $2300), ignition coil failures ($80 x 6 coils +labor), alternator ($900 at the dealer), O2 sensors ($100 x 4 + labor), cat converter (don't even ask the cost for that), etc.
These are not rare problems, they are common. Visit maxima.org and do a bit of searching, you'll see the problems people are having. If I had it to do over, I'd have bought a Toyota or Honda rather than my 2001 Nissan.