Changing the Transaxle Fluid in an Aston Martin V8 Vantage

DISCLAIMER: As always, follow all safety protocols. Don't undertake this task if you aren't comfortable with it and fully understand it. You are ultimately responsible for anything you do. Neither Redpants, LLC or myself is responsible or liable for anything that may occur.

First thing's first: The SportShift (also called ASM) has solenoids that need to be cycled in order to properly flush the clutch line. This can only be done using an AMDS. Whatever you do, do NOT drain the clutch bleed point if you have an ASM.

Second thing's also first: The SportShift is calibrated for a specific gear oil - Castrol BOT270A. If you don't use that gear oil, Aston may deny any warranty claims if anything happens to your transmission. There are a number of people out there using Motul Gear 300 in their SportShift transmissions and I haven't heard of any issues related to it, but do be aware of this.

Regardless of what gear oil you use, the process for changing it is the same. In this video I give a quick overview of gear oils and options for the V8 Vantage:

The DIY detailed below is the process I used for changing the gear oil in the manual transmission of my 2007 V8 Vantage. The process may vary for other years and models.

This video helps show how to do the job:

NEEDED
5L of Motul Gear 300 or Castrol BOT270A gear oil
Gear oil change package
T27 Torx Bit
14mm Hex Bit
22mm Socket*
8" extension for 22mm socket*
8mm Socket
Ratchets for the above bits, sockets, and extension
Fluid pump for gear oil (optional)
Drain pan (6+ qts capacity)
Jack, jack stands
Paper towels

*Instead of the 22mm socket, extension, and ratchet, it may be easier to use a long 22mm box wrench. I didn't try this so I'm not sure which method would be better.

Before you begin
1) Make sure you have ratchets that work for each of the bits, sockets, and extensions in the Tools Needed list.
2) Make sure your fluid pump fits the bottle(s) containing your gear oil.
3) Very briefly drive the car to get the gear oil warmed up. Don't drive for too long because the exhaust (and everything else under the car) is also getting hot. You only want the gear oil warm enough to flow smoothly to help it drain. It doesn't take much.
4) Have paper towels ready. Everywhere. This isn't a messy job but gear oil travels from surface to surface very easily so it's good practice to keep things clean at all times.

Here's the oil I'm using, which I also sell in my online store. The specified capacity of the transaxle is 4.7 liters.

Step 1
Get the car on jack stands. Ensure the car is properly supported before continuing. Let the exhaust cool off before you get started - you'll be working around it and you can easily burn yourself if the exhaust hasn't cooled.

Step 2
Use the T27 torx bits to remove the rear undertray - it's the big plastic piece that covers the muffler. Once removed, very carefully check to see if the exhaust pipes are cool enough to touch. It's likely you'll come into contact with the pipes and you don't want to accidentally burn yourself.

Here are the two plugs for Steps 3 and 4:

V8 Vantage transaxle drain and fill plugs.

V8 Vantage transaxle drain and fill plugs.

The single red circle on the bottom of the transaxle is the 14mm hex bit drain plug. The double red circle on the side of the transaxle is the 22mm socket fill plug.

Step 3
Use the 22mm socket, extension, and ratchet (or 22mm box wrench) to remove the fill plug (double red circle in the pic above). This was the most difficult thing to get loose during the whole job. It's securely tightened but once it 'pops' it comes out very easily.

Step 4
Place the drain pan below the transaxle and then use the 14mm hex bit and ratchet to remove the drain plug (single red circle in the pic above). Old gear oil will flow out as soon as the plug comes loose. Replace the copper washer on the drain plug and then you can reinstall the drain plug when the gear oil draining slows to a sparse drip or stops dripping entirely.

The drain plug has a magnet that collects metallic debris from the transaxle. It is very difficult to clean because, well, it's a magnet and the stuff you're trying to clean off wants to stay stuck. It looks scary, like this:

V8 Vantage magnetized drain plug collects metallic debris.

V8 Vantage magnetized drain plug collects metallic debris.

Step 5
Use the 8mm socket to remove the bolts on the transmission filter. These bolts are not on tight and don't take much effort to loosen. Remember this when reinstalling the filter. Do not pry the filter out!! It is made of plastic and can easily break! I used a very small flat-head screwdriver to very gently break the seal of the o-ring keeping the filter in place. Once the o-ring pops, the filter comes out easily.  Gear oil will come out. The filter is right here:

V8 Vantage transaxle gear oil filter location.

V8 Vantage transaxle gear oil filter location.

And this is what the filter looks like (as well as the fill plug and the copper washers)

V8 Vantage transaxle filter.

V8 Vantage transaxle filter.

Remove the rubber o-ring, then use brake cleaner to clean the filter. I also used an old toothbrush to gently clean away some grit that had collected on the filter mesh. Let the filter fully dry - blow on it if it makes you feel better... I did - then put the new o-ring onto the filter and put the filter back into the transmission. Fasten the 8mm bolts back in place.

Step 6
Ensure the filter and drain plug are both in place and properly tightened. If so, you can start filling the transaxle with new gear oil. Use the proper quantity as stated in your owners manual. If gear oil starts coming out of the fill plug, it's a good time to stop pumping. Once done filling, reinstall the fill plug with a new copper washer and tighten.

Step 7
Double check to make sure everything is back in place and ready to go, then reinstall the undertray, then you can lower the car back to the ground.

Before you go taking off driving, turn the car on and listen for anything that sounds odd. When you start driving, listen for odd noises, odd feelings, or anything else that stands out. You just want to make sure you're good to go before getting on the gas!