Trans fluid versus engine oil

Jun 23, 2010 2 Replies

This is a head scratcher. I've got a gas 88 300E burning oil. No biggie, seals and guides for sure because compression is good on all six, good oil pressure as well. So it isn't rings.



300K, time to do seals/guides. Been there done that before.

I keep a close eye on the stick; oddly, oil level never seems to go down. Now I've seen what coolant and oil mixing as a result of a bad head gasket looks like - chocolate milky looking coolant, or visa versa, coolant mixing with oil = milky looking oil. This isn't what's going on here.



I know these 300E's pretty well. There is 100% no way trans fluid can find a way into engine oil is there(?) since trans oil only goes to the rad to be cooled, then back to the trans - engine oil doesn't, so there's no union anywhere where oil/trans fluid can meet.



So what the heck is with this engine burning oil, yet the levels always show full on the stick?



You are probably burning transmission fluid... vacuum modulator on tranny can leak and get sucked into vacuum system into intake manifold.

The mixing of trans fluid anc coolant can also occur at the radiator.

Do a pressure test on cooling system to see if you have any internal leak.

Does your car have a load leveling system? That pump can leak hydraulic fluid into your engine crankcase and raise the oil level.

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