M66 drain plug thread size and pitch
 

Hi,

Does anyone know the thread specs of the M66 drain plug, please?

Thanks

I don't know for sure, but I think it is M18 x 1.5 x 12

Thanks,

I get the same from this site, but considering the original plug takes a 24mm spanner, it just seemed odd:

https://shop.motorsport-developments...plug-348-p.asp

I suppose I'll buy and if it's wrong, send it back.

It does take a 24mm spanner and from memory it's a lot bigger than M18, more like M20 or 22.

Both fill and drain plugs are the same size if memory serves, why not pull the fill plug and measure with a venier.

2.2 litres needed to fill the box, my hand book said 1.9 but lied.

Paul.

Yes, I think that's where I got the sizing from when I was looking a while ago. I didn't buy in the end due to the uncertainty.

Thanks, that’s a good tip. I’ll see what size the fill plug is...

Hi,

VIDA shows them being identical and M18x1.5x12 which is what I have been sold.

Only problem now is that I can't see the actual fill plug on the 'box...

Above the drain plug slightly to the rear on the same face. Reach from the nearside once the wheel is off with 24mm socket and long extentions. Drain plug you can get a spanner on but the fill plug is a lot easier with the soctet and extenton bars.

Paul.

Are you just replacing the plug, or fitting a rapid drain (like a FEMCO?)
https://www.femco.com/

I do not know the answer to your question, having changed the gearbox oil on my car the femco typeplug is not needed. I did however consider a magnetic plug and will ppossibly fit one next time.
The gearbox holds 2.2 litres of oil, I like to change it every couple of years to keep things fresh.

Paul.