May we ask you a question? How often do you change your engine oil? If you are an avid car enthusiast you probably change it every 3,000 miles, right? Oil manufacturers and tune-up shops constantly drive home the importance of changing the engine oil every 3,000 to 4,000 miles. Let's get one thing straight; their motivation for this is the cash in your wallet. The more often you change your oil the more money oil manufacturers and tune-up shops make.
Now don't get us wrong, we will religiously change the oil in our cars every 3,000 miles. If we forget and start going over by 100 or 200 miles, we feel bad and think that the engine deserves better. We'll even sometimes change it before 3,000 miles if there is a long trip in the near future. In general, it is safe to extend engine oil changes to every 5,000 miles. If you commute in a lot of stop and go driving or drive in extreme climate conditions the interval should be dropped back down closer to the 3,000 mile range.
Now for another question. How often do you change your transmission fluid? Do you even remember the last time it was changed? Even the most savvy car enthusiast often neglects the importance of changing the transmission fluid. Unlike the engine oil that gets filtered there is no filter for the transmission fluid. Dirty transmission fluid increases wear on the syncros (manual transmission) and gears affecting shifts.
Changing the transmission fluid at regular intervals is even more important if you drive an automatic. For an automatic transmission dirty fluid can result in increased wear of the gears and clutch packs. Dirty fluid can eventually lead to a slipping transmission, eventually making your vehicle inoperable.
Besides becoming contaminated with dirt and debris, the transmission fluid will lose its effectiveness over time with the loss of viscosity and lubricity. Transmission fluid should be changed every 15,000 to 20,000 miles, more often if you take the vehicle to the track. In such cases, we would recommend changing both the engine and transmission fluid prior to every track day.
Similar to engine oil, there are different grades of fluids for different types of transmissions. Manual transmissions and automatic transmissions use completely different grades. The safest bet is to contact the dealership and ask what type of transmission fluid you should use in your particular transmission. There are also many aftermarket manufacturers that offer synthetic fluid for both manual and automatic transmissions. Some people use synthetics exclusively while others stick with the factory brew. There are advantages to using synthetics as they operate more consistently at a wider range of operating temperatures. It is also important to note that front-drive vehicles equipped with limited-slip differentials require transmission fluid that is formulated with special additives specifically for the limited-slip differential.
Changing your transmission fluid will increase shifting performance and increase the longevity of the transmission. If you love your car you would do anything for it, right?