Quote:
Originally Posted by Vantagelvr
Gearbox + Differential/final drive = Transaxle . One fluid ,one plug ,one check . Take the plug out put your finger in and you should feel it barely below the plug opening or it may actually dribble out depending how level the car is.
So, why then are they two different fluid weights if it is one fill?


Got one
Vantageivr

I wanted to respond to this thread but unfortunately did not have the time, so belatedly here goes.
Not sure you guys understood what the people on the lists were trying to explain to you, so I will try to be simpler. I don’t have a sport shift so on that topic I welcome comments or corrections.
Most cars have the transmission/gearbox bolted to the engine and a prop shaft connects the transmission to the differential. Checking fluids require checking the engine, transmission and differential separately, and they all use different oils.
Aston Martins, along with other sport and Grand touring cars moved the transmission/gearbox to the rear of the car, and combined the transmissions function with that of the differential. This combined part is referred to as the transaxle. The reason for this move is weight distribution, by moving the transmission/gearbox to the rear, weight is moved from the front tires to the rear tires, thus improving the handling of the automobile.
With the gearbox and differential combined into one unit, (transaxle) these two functions now share the same oil.
Your car has the sport shift gearbox, which adds electro-hydraulic control to the existing 6 speed manual transmission. (Uses a dedicated ECU to control hydraulic fluids to activate the clutch and change gears.)
This Sport shift gearbox is also combined with the differential and is referred to as the transaxle. Again this transaxle share and use the same oil.
Both Manual and Sport shift transaxle oils are checked in the same way. There is a drain plug at the bottom of the transaxle to drain the oil. The filler plug is located about a third up the back of the transaxle. The transaxle is full when oil starts to run out of the filler plug. Checking the transaxle fluid is done by removing the filler plug. If oil drains out, or you can feel oil with your finger at the bottom lip of the drain plug then the oil level in the transaxle is at the correct level. (There is also a filter that needs to be cleaned but that’s another topic)
Because the Sport shift uses hydraulic fluid to change gears that fluid I believe can be checked, but not having a Sport shift I don’t know how.
One final thought. Prior to 2009, some transmission on these cars had some difficulty going into second gear and reverse while cold. Aston’s fix was issued under bulletin 0236, which, among other modifications, indicates that specific, lighter oil must be used in the transaxle.
The oil (BOT 270A) is only available from Aston Martin dealers. It’s a bit pricy, but, especially with the Sport shift, I recommend it. (Sorry for the long post)

 

Thanks for such a detailed response, I now understand how it all works!.....Obv the manual is useless, Aston HO even worse, and the dealers don't like to give too much info away, although they are very nice to deal with!