Does Transmission Fluid & Differential Fluid have a time limit

[ctechbob]

Yes it would be hard to rectify a design fault like that.

The point was, most all AT's are vented to the atmosphere and collect water over time. The 8 Speed disaster just brought that to light in a very expensive way (For GM).

 

[50yr Street Mech]

Some do, some don't . Check you're owner's manual. The dipsticks on my old Toyota's transmissions say don't change on a little sticker on the stick. But, of course I change it. My Honda clearly gives you the mileage and what to change in the manual. Every car is different.

 

[burbguy82]

Porsche recommends trans and Diff fluids based on time as well as miles. Is there any reason for this as it seems unnecessary as there isn't combustion going on to contaminate the fluids? Shouldn't it be just based on miles?

moisture from condensation or others, to remove wear metals, and most importantly, because I am sure a Porsche gear box is not cheap.....

 

[50yr Street Mech]

If the car is a garage queen, moisture can still get absorbed thru vents, unless climate controlled....... I have a mini-split unit and a combo thermometer / humidity meter mounted on the wall. Try to keep the humidity as low as possible ( until someone, the wife or daughter, opens the garage door because their too lazy to use the front door ) I chew them out all the time for that, but get no place. ......They do it anyway. They don't understand humidity and fluids. Like talking to a wall. LOL. Anyway, if the car is a queen, and there is climate control, I wouldn't be too concerned about ATF or DIFF fluids. Brake fluid is in a whole different category. That must be changed at least every 3 years in a climate controlled garage queen. Not climate controlled ? Change the fluids. Parked outdoors ? Change the fluids.