Hello, what is this hidden dipstick in the DG250 automatic transmission for? By hidden I mean you only get to see it if the transmission is out of the car. As far as I know, there is no access to it from the transmission tunnel of the car ?

 

I have the BW35 so no idea but here is a wider shot showing where the dip stick is on the gearbox.



Looking at photos of my gearbox tunnel during my rebuild there is a hole that corresponds to this dip stick which has no use on my car with the BW35 box but might line up with the dip stick on the DG250. It is the round hole above the inspection hatch in the left side of the tunnel. Does seem a bit small to pull this dip stick out of though.

 

Cass yes, the wider shot shows where it is in my DG250..
I have not removed the center console, carpet, or insulation to see but if there is already the long tube ans dipstick for the transmission fluid, what is this for ?

 

I'm going to make a wild guess that early versions had only the 'hidden' dipstick and the level was checked and topped up from inside the car. After a while, complaints from owners resulted in the provision of one accessible from the engine compartment. B-W kept the hidden one for back compatibility. The only other possibility I can think of is that at initial fill or if the box is completely drained, there are two parts of the box that require filling (like a manual with overdrive, but more so).

 

On the DG 250 there is a dipstick that is accessible from inside the car by lifting the carpet. There is a bulge on the side of the tunnel. Engine compartment dipstick came on later models. Mk2 from June 1961 the dipstick for the automatic gearbox was relocated from its position under the transmission tunnel carpet to a more accessible position under the bonnet. This carried over to the S Type ultimately. Some early S Types had the old arrangement.
credit Taylor in essence.

 

Manual GB is filled to spill at fill point on side of transmission. Run & then re topped once OD is full. Manual with OD uses the OD pump rather than it's own.

 

somewhat confusing since the long dipstick tube in the engine compartment connects to the sump of the transmission and this short dipstick is at the top. My service manual does not mention it at all.
And yes Peter, it reminds me of the manual transmission dipstick in my first car, a 1969 MG-B,, hidden under the tunnel carpet.
Thanks all for the hints, now the question comes up: Should I put Type F fluid in there ?? Or leave it alone?

 

DG 250 should ONLY use fluid meeting Ford spec M2C33F or G.

 

Glyn, the owner's manual says Type F ??

 

Jose. Your car is not a good reference car. It is odd in many respects ~ a bit of a crossover hybrid. e.g. it has the sunroof headlining but no sunroof & many other oddities. And as we have discussed frequently on the Register there is no such thing as a standard S Type although major oddities mainly appear at beginning and end of production.

 

Yes. Type G supersedes type F. When the manual was printed type G did not exist. Type G is a slightly better product but either will do.

 

The frictional properties of Type F & Type G are identical which is what matters and allow minimal slip & quick lock up. Don't put Dexron anywhere near that transmission. It will allow excessive slip of the clutch packs & bands & they will burn out. It was made for GM Boxes that have far greater area of clutch packs & bands and made for greater slip & smoother change. Dexron is a GM trademark.

 

On MK1 automatic cars the hidden dipstick was accessed from the interior of the car. I can't vouch for MK2s as I never owned a MK2 automatic.
From memory there was a rubber bung you removed on the left side of the transmission tunnel.
When checking the DG 250 transmission oil level, it was essential that the engine was running and the transmission was in drive and it really need two persons to do it.
One person holding the brakes on and the other checking the transmission oil level.
Failure to not follow this procedure and only check it without the engine running would leave the transmission low on oil.

 

Same for Mk2 Bill until June 61 but you still have to follow your procedure. That is correct!

 

the one time I did remove the front seats and center console back in 2005, I remember a sandwich of carpet, yute, and a layer of a black material glued over the tunnel. I did not pull off any of the layers, just saw them through the edges. I was not working on the carpet, only on the center console because I was not getting any air through the rear seat Vent. Turned out the cardboard tube that runs under the center console was crimped flat by the wood support center piece of the console.
So I never noticed a hole for that dipstick.

When the engine and transmission were removed, I did notice the dipstick which looks like a Manual transmission dipstick. I though I had an automatic with overdrive too !!!

I guess it was a leftover from earlier fitments,, so I am not going to worry about it anymore. My S type has the long tube and dipstick leading to the transmission sump.

Thanks all for the explanations about this mystery dipstick. I can now proceed with other jobs like degreasing parts..

 

Thinking back to stripping my S Type to pieces there is no way this dip stick would be accessible through the rubber bung as the S Type has a large centre consul over the transmission tunnel which have to be removed to get to the carpet which would need lifting to get at the rubber bung. No wonder they changed it to the dip stick under the dash which is the same with the BW35 and the DG250.

 

As above cars with the DG250 had a hole in the transmission tunnel with a big rubber bung that you could remove to fill them with oil.

You can see it in the picture below.




On my 1959 MK2 this is the only way to fill the oil so you have to remove the front seat bases and centre console when you want to do it. On my 1967 MK2 it has a different gearbox sump with a take off for a remote dipstick and so you can do it from under the bonnet but of course as mentioned above the transmission needs to be in low with the engine runnings so its not something you can do on your own whereas from inside the car you can.

 

Some had a more pronounced pressing around that hole. but otherwise spot on.