Is this possible? Motor Oil mixing with the Tranny Fluid?

[Alin99]

Hi,

Is it possible for this to happen?

Here's some background info.. The car does not lose oil but, I am always forced to add more oil at fillup. As far as I can tell, it does not smoke... but the oil is disapearing. Last fillup, I added half a litre of the stuff.

Just today, checking into a problem that I've wrote about below, I opened the transmission fluid filler and a brown, almost oil black fluid came gushing out. It smelled briefly like transmission fluid. I put the plug back in before letting it all come out.

Could the engine oil be making it's way into the transmission? Since fixing an exhaust leak, I've been able to hear a disturbing noise that I've not been able to find it's origins. It kinda cranks. At times, it sorta sounds like it could be a bearing but not too sure.

It's mainly while driving straight and accelerating; from the drivers side it sounds like it's coming from the passenger front side.. but I'm not 100% sure. None of my friends drive stick so I can't compare while being on the passenger side but they're not too sure where it's coming from up front either... possibly driver side but.. not sure; (it's clearly not the driver side though!). I've lifted the car and it looks alright and the wheel does not move in and out to indicate the bearing. So, I'm left with either the overfilled transmission fluid; would that make a weird noise if overfilled? The bearings, or something else.

Any ideas? On either subject?

[Bitter]

no, engine oil and transmission fluid are not connected.

[cipher93]

Oddly I have something very similar to both your issues. I was loosing oil mysteriously too, but ruled out the head gasket and eventually narrowed it to both a leaking oil pan gasket and valve cover gasket coupled with normal use/break down. I did however think it could be leaking into the transmission, so I changed the transmission fluid (A/T)... while I did find a little oil in it, I figured it being from the previous owner just pouring the wrong thing in as there wasn't much of it (certainly not equal to the amount lost). There really isn't anyway it can get into the transmission. Check and make sure it's not leaking around where the engine mates with the transmission though, as it could be a rear main seal if there is oil then.

Would you describe the noise as a grinding sound? Does it happen when driving, or will it do while parked? If it does it while parked, it rules out the wheel bearings or anything in the suspension. I would check if it's something loose on or in the exhaust system first.

[Alin99]

The only "wet" area that I can easily see is around the power steering fluid and below it. The engine is pretty rusted though. Do you think it's okay to allow this extra "transmission fluid" to run out? I heard the normal level is to the point of sticking a finger in the hole and seeing if it's wet... not it shooting out.. lol


As for the grinding noise, no it does not happen when parked (in neutral). I have revved the engine and it's only while the wheels are moving.

[Bitter]

manual trans?

[Alin99]

yes

[Alin99]

Well.. I just tried a new experiment and it's definitely not the bearing. While in gear the noise "happens" but if I drive the car in neutral, it's perfectly quiet.

Is the transmission failing? Will good new gear oil extend its life or at least make it silent? I know I haven't changed the tranny oil in the last 25k km and not sure the prior owner would have known to either... let's just say, when he sold me the car and gave me all his receipts, there was even one from when he got a bulb changed at the toyota dealership!

[musclecar64]

Change the gear oil. I'd say it's at least worth a shot. 75W-90 is what mine took. Make sure the car is level when you're filling it. (ie: lift front and back and place on stands). It needs to be replaced every 50K miles or so.