I have a 2015 Aston Martin Vantage GT with 4,000 mi on it I keep seeing on the forums that manual transmission fluid should be changed every 4 years or every 40, 000 miles. I looked in the car manual and there is no mentioning of every four years so I'm not sure where this came from. I have never had to change manual transmission fluid on other cars.
Please please see picture of the shedule of maintenance in the manual.
Am I missing something?
alex

 

You are not missing anything. Go by the what the manual says.

 

From the '09 owner's manual

 

Wow, so why 2009 has different maintenance schedule than 2015? They are suppose to be the same engine and transmission.

 

Interesting. I change my tranny & rear diff fluids every 2 years, along with the coolant and the brake/clutch fluids. Fluid is cheap, parts are expensive...

 

Manufacturers change guidelines from year to year based on things like fluids chosen, new testing, and even market demands. It seems unrealistic to expect the fluid to last forever independent of the mileage, but there are plenty of auto manufacturers who make claims of "lifetime" fluids even on cars with typical use. I worry about things like water intrusion, oxidation and metal particulate concentration.

 

I suppose there's no harm in over-changing, but depending on mileage, it's probably not necessary. There are ways of testing many of these fluids tor integrity if it ever comes into question.

 

Like others have said fluid is cheap and it’s easy to DIY . Also if you never drain the fluid and pull the filter out of the transmission you have no idea what’s going on in there .
Change it check the filter and look at the condition of the fluid and filter and that gives your a guide as to when to do it next based on mileage and how you drive your car .

 

The transmission fluid breaks down over time, not miles driven. If your transmission fluid is over 4 years old and it is replaced you will notice a difference for the better when changing gears.
It is however expensive when performed at the Dealer.