John Braconnier, President of Trans Tech Transmission
This is the most frequent complaint that we hear from customers. Because all car transmissions have leaks. I explain it to people this way, “A transmission is a pressurized unit”. A good example of a pressurized system is leaving your garden hose with full pressure on it all times. It would eventually start to leak.
So picture a transmission that has 10 times the amount of pressure in it compared to your garden hose. The transmission also has to put up with hot and cold temperatures and moving parts that further affect the pressure.
Remember that your average transmission has no less than 10 exterior seals to hold this pressure within it. After we repair a transmission leak, it doesn’t mean it will never leak again. We find that you repair one seal one week, and 2 months later you can be repairing another seal. This can be aggravating, but, ‘it’s the nature of the transmission.”
Low fluid in a transmission for a long period of time could cause extensive damage because it will affect the pressure and friction related operating parts. Too much fluid will not cause internal damage, but, over a period of time, could cause leaks because of the effect on the pressure.
And remember, in cold weather it is even more important to have correct fluid levels. My advice is to let your vehicle warm up in very cold weather.