Thread: Auto transmission overflow

There have been a few posts stating it is good to overfill them,,,

was it leaking before you had it serviced?

I had taken it in to have other leaks fixed but this appears to be a new leak. I had leaks and service done at the same time. Mech says this is new the fluid on the ground is red and appears to be new ie no discolouration to it.

I have looked at the goodoil site but I struggle to understand not very technically mnded.

Nobites

check www.discovery2.co.uk, look at servicing the auto, you will find they have to be overfilled. fill to overflow when still, then have someone start engine and move gearshift through p -1, and you can get another litre or so into them before they overflow again.

there are no adjustments,,
just drop the sump, clean/replace filter replace sump.

There is a set of instructions on how to fill one properly though

the correct fill is done with the engine running after you've cycled it through all the gears and have it in neutral.

fill it up then allow the excess oil to run out untill the bead of oil that is flowing out of the hole is 2mm in diameter.

now, thats kind of ambiguous so heres how I define it.

the "bead" of the oil is the point where the flow of the oil first goes from being oval shaped from coming out of the fill hole to being round. When the oil comes out it will be initially U shaped it then takes a 90 degree turn as dictated by gravity and pulls back in towards the socket due to surface tension. once the oil is free of the socket and falling it will start to form a circular "tube" of oil this is where you want to measure, the start of that tube. Typically this is a point about 5mm below the bottom of the fill socket.

First up thanks to all for your replies I do appreciate it. Just to clarify my problem is the transmission leaking after it was filled and I was trying find out if there was a safety release mechanism to release pressure if the transmission was overfilled and heated up.

So from what I gather from your post pedro is if the transmission was overfilled then when the fluid became hot and expanded there is no safety relief mechanism and with the build up of pressure it would blow a seal. Would this be correct.

BiKnight the flow that I saw coming out of the filler hole was a steady stream that projected 1 inch from the hole before gravity started to drag it down. The transmission was hot when this was done.

I washed the engine bay down today and had a look from the top to see if I could see where it was coming from (why I dont know as I have no idea how to fix). The fluid seemed to be pooling on a 'shelf' on the side of the engine just in front of where the transmission is connected to the engine if that helps with any ideas.

Again thankyou all for your assistance and I apologise for my vague description but I am not very technically minded.

Nobites

thats normal for a hot transmission thats been standing for more than about 10 minutes.

As the filler hole doubles as the level indicator unless you turn the D2 on its side I'm not sure how much you can overfill it.

As it is,
its probably now running underfull---