Big Leak - Mk9 Borg Warner

Hi -

I have a steady stream of oil leaking out of the left side of my Borg Warner Automatic on my Mk9.

I think this is a fairly common problem… can it be fixed with car in situ, and what do I need to do to fix it?

Thank you!


A Mk9 will be have a DG250.
This week I had a major leak on my DG250 ( MK1 ).
In my case is was the seal of the rear oil pump ( right side rear), I changed that with the box in Situ.
This and the sump seal are about the only 2 you can change with the box in situ.
First you need to figure out where the leak is coming from.
If it is leaking out the front the seal, the box need to be removed.

The selector seal is a place that most Trans eventually leak.

It is where the gear selector penetrates the body on the side (not exactly sure on a DG250)

Clean everything up with degreaser and towels to see where the leak is from

Once you have identified the leak, you can be advised how it should be repaired

Thanks all, I had a looksie under the car and it is dripping out of the speedometer cable, so seems I need to take the speedometer drive out and replace the seal on it. As I understand this can be done in situ but looks like I need to have monkey hands to work around the exhaust pipes

This is a little off topic but the MG T series cars were known for speedometer pinion oil leaks. They apparently had no “seal”. There is a fellow in the T Series world in Arizona who takes your pinion, cuts a groove in it and fits an O ring thus curing the problem. Worked great on my TD. I do not know the exact set up on the BW DG250.
Another potential leak on the DG250 is the intermediate speed hold solenoid which is sealed with a rubber bellows that perishes letting oil out. There have been posts on how to change this.