List of some likely possibilities (besides disastrous mechanical failure).

1. Bad fluid. Pump out ALL of the trans fluid professionally. Try http://www.aamco.com See my other post in another thread.

2. Neutral-Start safety switch. It's mounted to side of the transmission. It tells the trans computer which gear is selected. If replacing, be sure to adjust it properly upon installation. (It's a slotted mount like a distributor). You'll need an ohmmeter and a service manual to do this.

3. Trans computer. (Is it seperate from engine? I do not know).

3. Solenoids in the valve body. These are probably okay, if not, they will probably recover if you change out all of the trans fluid. They could be corroded, though.

4. Torque converter. If there is water in the fluid, it can slip. It could also be damaged inside, causing slippage, but this isn't usually intermittent.

5. Bad stator. This is the thing that lets the trans slip while coasting (and grab under power, like a ratchet). If it has come only a little loose at its attachment point, it could work fine while cold or under light load but break free when power is applied or some heat builds up. This is internal to the transmission. You'd probably find little pieces of metal on the drain plug if this were the case.


Finally, what gear does it slip in? It makes a big difference whether it's all gears, or a particular gear.

Nate