Replacement Matlab Program for Farm Machinery

Contact the equipment manufacturers directly. They will have the best data.

Replacement data is usually related to hours of run time and type of use.

.." five year estimated useful life with a 25% salvage value,"...

Book....

http://www.wikinvest.com/stock/H&E_Equipment_Services_(HEES)/Rental%20Equipment

I assume that you are looking towards the practical lifespan of agricultural equipment? Not the financial model - that depends on local accounting practices and tax-related depreciation allowances and rules. My guess is that you have to balance production (a function of reliability, amongst others) with costs. Costs would include maintenance costs. then you have to draw the line as to where the reliability cannot justify the cost increases, the law of diminshing returns starts to apply

The problem is that it depends on the owner's financial situation to an extent, as well as how well the operators look after the machinery, redundancies (are there many similar machines), etc. Another factor is the increased production or lower costs (lower fuel consumption, longer maintenance intervals, lower maintenance requirements) of newer models. My brother-in-law hangs on to his critical tractors for about 10yrs+, but a combine harvester would probably last for around 20 years (with major maintenance interventions at times, I know!), and some of the smaller run-around tractors are probably older than 20 yrs.

The manufacturer can assist with maintenance schedules and costs, but not with replacement periods (they would want you to buy a new one every year!) I suspect that some big players in your trucking or fleet leasing industries can assist you with their methodology - it could point you towards the correct questions in your unique environment?

Good luck!