Leaking Oil...but where from?

[thehinch]

I bought a 2003 Diesel X5 a few months ago and its started to leak oil from under the engine. I've been monitoring the engine oil and power steering and they seem to be fine.

Does anyone know what it could be that's leaking? Could it be from the front differential?

[TwinTurboGTR]

It could be anything. Crawl under and see where it is coming from. It could be oil seeping past an oil ring, tranny fluid, TC fluid.. anything. Take a look and come back.

[nebilex]

If under carriage is as soaked as mine was, u will have a hard time finding the source.. Common oil leaks on the 3.0 gasoline: ccv, oil filter housing gasket, valve cover. I dont know if the same would apply for the diesel engine but worth checking. Good luck

[ake53]

having the same problem on 3.0i the complete oil pan seems to leak. Will replace oil pan gasket and new bolts. hard to find your problem. take it to a car wash that does underbodyrinse and than take it on a lift and see.good luck

[Skyline]

I would start by getting it on a lift, removing the reinforcement plate, and see if the source of the leak is obvious. If not, the next step is cleaning everything with de-greaser, then bolt the reinforcement plate back on and drive the car a few days. Chances are it's going to be quite a messy job, so be prepared for a huge clean-up of the shop floor. After driving a bit, then get it back on the lift and look again. An option is to add UV dye to the oil, and look for the leak with a UV light and yellow glasses.

And don't forget that when you're ready to button things up underneath, you need to replace and properly torque the bolts for the reinforcement plate. They are torque-to-yield "single use" bolts.

Given the fact that we are talking about an X5 here, don't be too upset if oil is leaking from more than one spot.

[jgold47]

before you do all that, take a white rag and dab the dripping oil. Report back with the color and the smell (dont laugh). There are 6 fluids in the front of the car. Engine Oil, Brake Fluid, Coolant, Power Steering fluid (ATF), Transmission oil and front diff oil.

Power steering and ATF are red, and should smell different from each other.

Brakefluid is amber colored and smells about the same new as used.

Front diff fluid smells terrible and is usually dark almost black

motor oil is its own thing

coolant could be green, blue, orange or piss colored, but will smell sweet

oh, and washerfluid. blue usually, distinct smell from coolant.


learn to identify fluids by color and smell and you will narrow it down.

[nebilex]

Agree with both jgold and skyline.... When the oil filter housing started to leak, I had no idea where it was coming from. The oil pan was completely covered and thought that was the problem too.. But when I took it to the shop, the mechanic told me considering the mileage on my car (140k) it's probably safe to look closely at the oil filter housing and also do the ccv... He cleaned it up and told me to drive around for a bit and come back in the afternoon. Then he called me back saying it was the oil filter housing gasket, so got both those done. He showed me the gasket that he took out and it was in 1000 pieces, it was real brittle.... Hopefully you can diagnose it quick..

[thehinch]

The oil is not red or black in color. Its hard to describe the color. When i smear it over my fingers its close to being clear in color which is confusing and doesn't line up to your list jgold. I haven't yet smelt it and I'll do that when I get home.

From underneath the car the leak is not coming from the oil drain plug (right side of engine if standing at the front of the car). The leak is coming from the other gap in the reinforcement plate on the left side. Does this help with troubleshooting?

[jgold47]

I've got this. For 1 case of fosters its the o ring on the lower coolant hose temp sensor.

[thehinch]

Mate...if you can send me a link to the DIY step by step instructions on how to fix it I'll give you a case of fosters and room full of hookers )