Engine oils degrade with use and become dilute; hence it is desirable to change them frequently and that this is an effective method of preventive maintenance. In this business, you ought to make sure you have a set of all instruments vital for the project and many rags in anticipation of a stain. Start with engine at normal operating temperature; this produces better flow of oils and sludges. After warming the vehicle turn off the engine, find a level and flat ground and take off the oil filler cap. The oil drain plug and filter is more easily accessible if the vehicle is on a hoist or jack stands; always avoid working under a vehicle that is only on a jack. Carry the jack under the engine in the manner to avoid the hot exhaust parts and find the drain plug and the oil filter. Place a drain pan underneath the plug, clear the area, and when removing the plug take keen on hot oil. When the oil has been drained, look into the oil for metallic debris, and check the drain plug for deposits, clean it and bolt it tightly back in its position. After that, place the drain pan beneath the oil filter, and using a filter wrench, remove this unit; in case the filter is quite tight, it is possible to use a metal bar for its turning. When already opened, twist and remove the cap while in an angle to avoid spilling of the contents. While putting on the filter, remove all the old gasket from the mounting surface on the block and examine the used filter to the new one. Apply a little engine oil on the gasket of the new filter then fit it into position and tighten it in the right manner. When all the tools and materials are taken out, lower down the vehicle and put in fresh oil through the filler cap with the help of a funnel and put in four quarts and pouring the dipstick. Cranks the engine and check for drips at the drain plug and filter and if there are some then using the spanner tighten them. Check the oil level again after some few minutes and add more if the quantity is low. The first few times when you are on the road after a modification, your primary observations should be the leakage and the level of oil. Last but not the least collect and dispose off the used oil that cannot be reclaimed by pouring it into container for possible disposal.