4000 hours on a tractor is a lot of hours although it doesn't mean the tractor won't last even longer.
A well maintained tractor can last over 35,000 hours and sometimes longer.
A tractor can last for 20 years or even longer if well maintained and not abused.
Some tractors are still operating and being used at 80 years and longer but the newer tractors may or may not last that long.
As long as you maintain the tractor it should last at least 20 to 30 years.
When a tractor has more than 35,000 hours it's considered to be high hours on a tractor.
However even if a tractor has high hours it still may be a reliable tractor and have lots of years and hours left in it
As long as the tractor is well maintained it can last longer than a tractor with lower hours that hasn't been maintained.
If you can get the tractor with high hours cheap enough it can be worth it.
If the tractor has service records that show it's been maintained and serviced regularly that can mean a lot as well.
Many tractors that are well maintained can last several hours and several years.
A tractor that has 1,000 hours or less is considered to be reliable and have many years left in it.
A tractor that has 2,000 to 2,500 hours is considered to be well broken in.
And a tractor that has 4,000 hours is often still a good value if it's been well maintained.