What is this bolt for on 722.366

[Gmach]

I have a small leak on this transmission and the bolt circled in the picture is wet.
It may or may not be the source so I decided to replace the washer on it.
I have looked everywhere to get a part number for the washer so I can order one but cannot find it listed anywhere.
The EPC I use doesn't even show the bolt.
I have seen it in photos of the transmission in different service sites but it is never described.
I took the washer with a location description to the local dealer hoping they could ID it but they couldn't find a listing or description.
They looked for a similiar washer and couldn't find one that size either.
Does anyone know what it is for and if there is a part number for the washer.
Transmission is a 722.366 and this is located on the drivers side just above the oil pan....which has been removed in the photo.
Thanks

 

[JC220]

I have a small leak on this transmission and the bolt circled in the picture is wet.
It may or may not be the source so I decided to replace the washer on it.
I have looked everywhere to get a part number for the washer so I can order one but cannot find it listed anywhere.
The EPC I use doesn't even show the bolt.
I have seen it in photos of the transmission in different service sites but it is never described.
I took the washer with a location description to the local dealer hoping they could ID it but they couldn't find a listing or description.
They looked for a similiar washer and couldn't find one that size either.
Does anyone know what it is for and if there is a part number for the washer.
Transmission is a 722.366 and this is located on the drivers side just above the oil pan....which has been removed in the photo.
Thanks
View attachment 130117

IIRC the original seal ring is aluminium. You don't need to get this from the dealer.

It is just a crush ring - try to find a standard one at an autoparts store of same size. or Copper and anneal it before installation so it bends in your fingers easily. It's handy having a few ebay or amazon crush ring sets around for jobs like this. Just pick one that is a suitable size and it will be fine.

 

[500AMM]

I think it is a blind plug for a port for attaching test equipment, port M in your case.

 

[gsxr]

@JC220 and @500AMM are both correct. It's a test port, and uses an aluminum crush washer / seal ring.

It is in the EPC, but not obvious as it's shown on the opposite side, because there is the same plug on both sides of the transmission.

 

[Gmach]

Thanks very much. It is a test port.
I will get a crush washer from Napa.
I replaced it with a copper injector washer but I didn't anneal it.
I'll do that right now.
Good advice. Thanks