Its well past time to flush the tranny on my 96 960...
I purchased 40 litres of OEM fluid. Ive never done an tranny fluid change on one of these... is it as straight forward as an engine oil change? How much fluid should come out? Do i need to replace the filter as well?

 

No, it is not quite that simple. And I think you bought way too much fluid.

To do a flush you will have to loosen the upper cooler line on the radiator, remove the pan contents, and replenish outgoing fluid.

Draining the pan only gets to 2-3 qts, if I recall correctly litres and quarts are fairly close in volume.

To do a flush you will need 12-13 quarts. A container that will hold multiple quarts with markings for every two quarts, a hose that will extend that freed cooler line into the marked container. A nice long funnel that fits into the trans filler neck.

Start by draining the pan, and pour in new fluid, replace only the amount that was drained. Do not start the engine until you are set up to drain into the marked container, doing so will send that fresh fluid in the pan into the transmission and old fluid will now be sitting in the pan. Next, set up your hose on the cooler line and place it in the marked container, you may have to place somewhere under the hood so you can see it while it is filling, if you are alone that is. Having someone one to assist is great help. The goal is to run the engine at idle until two quarts are drained into your marked container, stop the engine and refill the trans with fresh fluid, always taking great care that you replace only what was drained. The idling engine only takes about 15 seconds to do the two quarts. The reason for only doing two quarts per idle is because the pan only holds that amount and if you were to continue any more then the trans would start to suck up air, not a terrible problem but would cause your drain hose to slop fluid everywhere. If your used oil is not bright red, then it will be very easy to tell when you have all of the old oil out, it takes 11-12 quarts before the drain hose will have bright red fresh fluid.

The hardest part of this is breaking loose the cooler line from the radiator and then feeding 12 quarts of new fluid in the tiny filler of the trans. Dealing with the cooler line, use a quality line wrench and be sure to hold that large nut still, don't let that turn. When finished and you are reconnecting the cooler line, only use fingers to get that fitting started, cross threading can be done easily.

Now, I suggest using synthetic fluid, but if has been a really long time, then I would use regular fluid, let it run 5,000 miles and then replace again using synthetic.

DanR '94 964 350,000 miles (115,000 miles on the new engine)

 

Sounds a little tricky. How much does the dealer and/or shops change for a tranny service?

 

I've seen a "Jiffy Lube" sort of place charging $80 for a true flush. It really isn't that tough.

 

ANY WAY TO CHECK FLUID LEVEL AND CLAIRITY? I don't see a dip stick.

 

Dipstick is way down in the engine bay on the drivers side. It's almost as easy to get to it from under the car while on ramps. Has a yellow stick.