Good morning! Please help me? I have BMW 540i. produced in 1994 year, December. I have problem with transmission, the front oil ring is leaking and I replaced it two times. What should I do?

Excess unburned hydro carbons can be difficult because the cause can be both engine oil and fuel related - even low quality engine oil can be a factor, especially if the car is used for lots of short journeys.

Considering the age of the car there could be some oil consumption issues, principally from the valve stem oil seals, blocked or inefficient crankcase breather or piston ring/bore wear.

Poor fuel injector spray patterns producing a too-large droplet size can increase the amount of unburned fuel as can a leaking injector.

You do not say where the leak is; front, middle, or back of transmission.
There is a 210mm x 3mm o-ring and 128mm x 3mm o-ring for mating parts. There is a fill plug with o-ring on the side, a drain plug with o-ring and an oil pan gasket on the bottom. Common causes are age of the o-ring or gasket material, pinching of the o-ring during installation, or failure to have a clean surface for the gasket during installation. This assumes all fasteners have been properly tightened.

On this website you find fuse box diagram and description for BMW 5 series (540i)

BMW 540i E34 1991 1994 fuse box diagram Auto Genius

No, if the oil pump went bad the engine wouldn't get lubricated at all, then it would sieze.

That's like saying I'm bleeding, my heart must be bad. Not so, no heartbeat, no blood pressure.

It's good news for the oil pump that it's burning oil, at least, the pump is moving oil around the engine for it to be burned.

Bad valves or piston rings will burn oil. Most likely piston rings

Same as an Automatic Transmission ATF.

Try asking here for free 

www.ukbookshelf.co.uk

If it is available  then this place will definitely help...especially on these  older BMW radios

I own a 1994 BMW 540i with an automatic transmission. The filler hole/plug is located under the transmission oil pan. Picture in your mind an inverted cone with a hex plug inside the top of the cone. You will need to remove the plug and pump fluid into the pan until it overflows. Also, this must be done with the engine running and the transmission in neutral.

Do not try this unless to you have the proper equipment to raise your car, keep it level, and have four jackstands in addition to the special fluid and pump.

well, when you changed the oil filter, did you make sure to clean the surface on the engine side? make sure the last o-ring came off with the filter? Lubricate the new o-ring before installing?

You must check to see if you have power at the fuel pump relay which is probable in a fuse box under the hood.

1. You need an oil filter made for your year and model of bmw.
2. The 540 is the 8cyl version vs the 528 is the 6cyl version
3. yes, you can go back and forth from regular to synthetic oil with no problems