Our transmissions are manufactured to strict original-equipment vehicle manufacturing standards, and they do not require much maintenance. The popular Magnum, TKX and T-5 transmissions are often installed in high-performance or race vehicles that require somewhat regular inspection.
In this article, we’ll provide a rundown of what to check, as well as how to perform an oil change on a TREMEC transmission built for aftermarket use. If you have a transmission that came as factory equipment in a vehicle, we recommend that you follow the vehicle-manufacturer’s recommended maintenance schedule and procedures.
For all of this work, the car will need to be elevated to give you access. Secure the car safely using appropriate jack stands. It’s important to check that all transmission and bellhousing bolts are tight, including the transmission mount fasteners. If these work loose, transmission damage can occur. Look for signs of oil leaks. Specific areas to check are where the transmission bolts to the bellhousing which could indicate an input-shaft seal leak, where the sections of the case come together and the rear-output shaft seal. Any leaks should be remedied; replacement parts and service are available through TREMEC distributors. Also check the driveshaft U-bolt fasteners. If these become loose, it can cause a driveline vibration, and can eventually cause a leak at the rear output seal. We recommend that the fluid in a TREMEC Magnum, TKX or T-5 transmission should be changed after its initial 500 miles. The fluid should be changed every 30,000 miles after that. You can use a high-quality Dexron III fluid, or TREMEC HP-MTF™ manual transmission fluid. We developed HP-MTF to provide rugged protection while maintaining responsive shifting. It takes the guesswork out of which oil is correct for my TREMEC aftermarket transmission.To drain the transmission oil, locate the drain plug. There are two plugs on the side of the transmission. The lower one is the drain and the upper one is for filling. Use a 3/8-inch square drive in the plug to remove it. Capture the drained fluid and dispose of it properly.Once the transmission is completely drained, clean the threads on the plug and apply a mild thread-locking liquid. Insert the plug and tighten until snug – do not overtighten! Then remove the upper plug.For most vehicles, you will need to use a pump and hose to get the new fluid into the transmission. Fill the transmission until fluid comes out of the fill hole. Let the excess fluid escape. Apply mild thread locker to the cleaned fill plug and install it in the same way that you did the drain plug. Wipe excess fluid from the outside of the transmission.
