I have a windstar which are notrious for transmission problems. The car has 157000 miles and has taken us on a lot of road trips. I am afraid if i change the fluid it will dislodge some gunk in the transmission and screw it up. The car has not been properly maintained. So should i fix what ain%26#039;t broken?|||that trans dont owe you anything, keep your change in the bank, you owe the trans if you get my drift.|||dislodging gunk in a trans is rare. Transmissions do not sludge up like engines do. However there have been cases where changing the trans fluid has made the trans worse. Here is the best explanation on why this happens:
Automatic transmissions have moving parts and fiber discs or clutches, not to be confused with a clutch in a manual transmission. These moving parts over time wear and release tiny particles into the fluid. On some transmissions that have never had the fluid changed and have severe wear, that old fluid is full of those particles. When you drain that old fluid out and then refill the transmission with new slippery fluid that does not have those particles, it can cause the clutches in the transmission to slip. Why now though? Simple, they are worn out and they had gritty fluid to help them grab or not slip. Now that gritty fluid is gone, replaced with smooth fluid.
Its a gamble to change it, but I think you should be ok to change it if there is no current slippage.
