A variety of transmission problems can manifest while driving your Isuzu Rodeo if your transmission fluid is too low or too old. These include delayed or erratic shifting, slipping gears, one or more gears missing and overheating. Hearing a buzzing or whining noise coming from your transmission is an early sign that your Rodeo's automatic transmission is beginning to fail. Although do-it-yourself mechanics are mainly limited to changing out the transmission fluid and the transmission filter, many problems can potentially be fixed or avoided with regular service of these parts of the transmission.
Turn on your Rodeo's engine and allow it to warm up before checking the transmission fluid. The Rodeo is adequately warmed up once the engine speed on the dashboard tachometer levels out between 400rpm to 800rpm. Open the bonnet on your Rodeo with the engine still running.
Remove the transmission dipstick and wipe it clean with a cloth. Re-insert the dipstick into the transmission dipstick tube and pull it back out again. If the transmission fluid is below the minimum level, as indicated on the dipstick, add more transmission fluid via a funnel attached to the dipstick tube.
Inspect the quality of the transmission fluid while it is on the dipstick. If the transmission fluid has a brown or black colouration, then it needs to be drained and replaced with new fluid. Smell the transmission fluid. If it smells like burnt toast, then it also needs to be replaced.
Drive your Rodeo onto a set of car ramps so that you can access the transmission drain pan and flush the transmission system. Shut down the engine and place a catch pan underneath the transmission drain pan. Unscrew the transmission drain plug and allow the transmission fluid to drain into the pan.
Unscrew the 16 mounting bolts for the drain pan. Unscrew the mounting fastener for the transmission filter and replace the filter. Clean the bottom of the drain pan with an automotive cleaning solvent. Use a plastic scraper to remove the gasket from the bottom of the drain pan and install a new gasket. Use automotive gasket silicone to seal the bottom half of the drain pan to the top component. Screw the mounting bolts back into the drain pan. Pour automatic transmission fluid into the dipstick tube with a funnel. Consult your owner's manual for the transmission fluid capacity of your Rodeo (The 2000 2.2-litre engine uses 9.2 quarts, for example).