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There are many different types of tractors on the market with a wide variety of applications and associated accessories. To be sure you properly maintain your specific make and model of tractor, you should read through the manual that came with it. Many tractors require specific types of lubricants and hydraulic fluids that you can identify in the manual. Using the wrong kind could damage your tractor. If you do not have a manual for your tractor, you may be able to find the information on the manufacturer's website. Before you get started with any planned maintenance on your tractor, give the whole thing a good once over to see if anything looks overly worn, broken, or dirty. Many newer model tractors even have plastic windows on fluid reservoirs to check things like hydraulic fluid levels. Give your tractor a visual inspection before and after each use. Make note of any issues you identify to make sure you address them before the next time you use the tractor. Use a tire pressure gauge on each tire and compare it to the tire's pressure rating written on the sidewall. Tractor tires can last years, but operating a tractor with under-inflated tires can ruin the sidewall and cause the tires to wear faster than they should. Under-inflated tires will also cause the tractor to burn more fuel in normal operations. You may want to adjust tire pressure for different types of jobs. For instance, if you plan on driving your tractor on the road, you might want to add a few more pounds of air. Reducing tire pressure on slick surfaces like mud can help increase traction. Tires lose pressure more quickly when temperatures change from cold to hot, so you may want to check your tire pressure more frequently in the spring and fall. Some tractors may not be equipped with any lights at all, while others could have an extensive lighting system that includes turn signals and interior lighting. Check each of the lights after each use of the tractor so you can address any electrical issues as they arise. If a light fails to work, it may be a blown out bulb or fuse that needs to be replaced. If neither of those solve the problem, your tractor may need to be serviced by a technician. Check your owner's manual to find the correct type of bulb or fuse needed to fix a bad light. Just like in a car, a tractor's engine relies on a number of rubber hoses and usually at least one belt. Look all of the rubber components over for signs of wear or damage. Excessively worn rubber components should all be replaced. Look for glazing on the sides and bottom of any belts that may indicate that it's been slipping. Any rubber that has cracked should be replaced. Depending on the environment you use your tractor in, you may need to change your air filter more or less frequently. Locate the air filter using the tractor's user manual, then visually inspect it. If it's really dirty, it should be replaced. There's no real rule of thumb with air filters; they should just be replaced as they appear dirty. You should check your air filter after 8 hours of use or so. You need specialized tools to check your tractor's hydraulic system. If you have the correct coupler fitting and a pressure gauge, you can connect it to any of the black ports on the hydraulic system while it's running, and compare that figure to the correct specifications outlined in the manual. If you don't have the correct tools, it's recommended that you have your hydraulic system serviced by a professional after every 500 hours of use.
Familiarize yourself with your tractor's manual. Give the tractor a visual inspection. Do a tire pressure check. Test the lights. Inspect the belts and hoses. Replace the air filter as needed. Test the hydraulic system.