Transmission oil sump leak on 2000 V70 automatic

Post by **FireFox31** » 01 Dec 2020, 20:25

Hello, my new-to-me 2000 V70 automatic with 200k miles appears to have a leak at the transmission oil sump. It is wet below and on the left side of the rounded rectangular cover protruding from the front of the transmission. On this transmission diagram, the oil is around part # 40. What could be causing this leak and how can it be resolved? Or is this fluid from somewhere else, considering how old it appears? Thanks.

Post by **abscate** » 02 Dec 2020, 04:40

Is that ATF or engine oil , Firefox?

Rub a bit on paper and see if it’s black or reddish brown.

I would wash that off with a citrus engine spray, then rinse at a car wash, and see if you can pin down the source that way

Remember, if it’s been doing that for 10 years it might just be a seep you can live with in your cars long term plan

Post by **kallekula** » 02 Dec 2020, 12:34

That return pipe has an oring on it. Easy to replace. Try cleaning the engine like previously suggested. Its hard to see where it leaks from. There are slso cheap dye kitsbyou can buybto help u see where it leaks using a uv light.
Good luck!

Post by **FireFox31** » 20 Jan 2021, 23:22

Following up on this: The pictures show the transmission valve body cover. It is sealed to the transmission using RTV silicone and nine bolts. I believe the silicone on mine has failed, allowing this fluid to leak.

Correction to my first post: The 2000 V70 has the AW55-50 LE transmission as shown in this diagram. The leak is around part #21 labeled "oil sump".

MVS user precopster is the authority on AW55-50 LE valve body work in the P2 forum. He created a P2 valve body replacement PDF which is exceptionally detailed. Some other useful valve body threads:
P2 transmission disassembly - https://www.matthewsvolvosite.com/forums/viewtopic.php?t=61600
Filter destruction - https://www.matthewsvolvosite.com/forums/viewtopic.php?f=9&t=82841
When the filter gets clogged, drill a hole in the body, reach in and destroy the filter, add an external filter, and plug the hole with a screw.
Valve body assembly - https://www.matthewsvolvosite.com/forums/viewtopic.php?t=62140

I may attempt to reseal my valve body cover. It requires raising the engine 20mm and lowering part of the subframe to gain access. I need to research which RTV silicone to use. It might be the $115 Volvo part 1161409 but I'm not sure yet. I'll take any input I can get.

Post by **abscate** » 22 Jan 2021, 02:03

There will certainly be a Permatex equivalent or better for about$10, let’s try to find out which one it is.

So far, one recommendation on Swede speed for permatex 81182

https://www.amazon.com/Permatex-81182-G ... GM2KK?th=1

TASca has the Volvo product for $77

Post by **FireFox31** » 07 Feb 2021, 21:55

I finally cleaned the transmission valve body cover. The transmission fluid level was perfectly at the top of Hot on the dipstick (after driving 30 mins, engine running, having just cycled through the gears). This makes me think the cover is not leaking. Perhaps it's engine oil running down from the top of the engine where the oil fill cap has an old cracked gasket. I'm going to clean that next.

It's funny how the coating of dirty oil protected the metal beneath from rust. Look at the bolts on that top picture, exposed rusty vs. oil soaked clean. Makes me wonder if the annual Fall oil undercoating which some people do is actually beneficial.

Post by **erikv11** » 08 Feb 2021, 17:18

Nice clean-up job!