My 1985 300D has a transmission fluid leak near the front driver's side. It appears to be leaking from a rubber hose that goes between the engine oil filter housing and a mini radiator next to the main radiator. But that can't be I don't think. It drips off the bottom of the A/C compressor.

The leak is serious enough that if parked for a few weeks or months, a quart or 2 of red tranny fluid will leak out, and it will leave a red pool on the floor and then shift funny.

Just for good measure, changed the trans filter and gasket, & carefully torqued the bolts. The leak is definitely not from the pan.

Does any one know of a common cause for this type of leak?

Thanx!

This sounds like a leaky trans oil cooler line.

to verify:
wash the trans oil cooler lines - run up to temp, shift & idle in each gear position (you don't need to drive it), shut it down and recheck the lines for wet/leak.

Good luck!

That sounds like an engine oil cooler line problem.

The automatic transmission cooler lines are more or less each side of the engine running to the bottom of the main (big) radiator. The engine coolant radiator is split in two - lower part for the transmission oil - upper and bigger part for the coolant for the engine.

The mini side radiator is for the engine oil. There are many reports of these oil cooler lines going and taking out the engine - the oil pumps out pretty quick. Just for the potential mess it will make it is worth not driving the car until it is fixed.

The problem with fixing these lines is that the cooler lines tend to "weld" themselves to the cooler (little radiator) - this happens due to dissimilar metal corrosion.

Many people have broken their oil coolers trying to remove the cooler lines.

__________________
1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!

Thanks for that. I guess I will go to the pick and pull to try to find one of those lines.

If you shop around the new replacement ones can be found for a low price. Second hand cooler lines are not something I'd be all that keen on...

...for starters the removal of old cooler lines is the kind of job I'd rather have to do just once in my life...

__________________
1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!