Recently I was asked about a 1994 ford ranger with the automatic overdrive transmission. The tranny fluid level keeps going down and oil level goes up. The engine oil is not milky but seems very diluted. A common question about transmissions that has an easy solution 99% of the time. Probably eliminating the need for an engine for sale.
You have the Ford A4LD automatic overdrive. It uses a modulator to help control the shifts. I’ll explain why next, however my bet is that you have a bad modulator on the transmission.
Engines naturally produce vacuum. Vacuum is highest at low throttle settings as in idling. Vacuum drops as you accelerate. If you hooked a vacuum gauge to your engine you would see that it drops to nearly zero under wide open throttle.
A modulator is a vacuum device, connected to the engine by a 1/8th inch metal line with short rubber connector hoses from the transmission. The modulator has a vacuum diaphragm in it that moves in and out as the vacuum varies. If the diaphragm ruptures in the modulator, it allows the engine to suck transmission fluid into it. The bulk of fluid being burned by the exhaust and the rest going into the engine oil. The first thing I would suggest is to have a professional mechanic check the modulator.
When you say the oil is not murky, it suggests to me that the problem is not the radiator. The radiator does have a cooling tank built into it to cool the transmission. It is connected to the transmission by metal cooler lines. When the divider between the engine cooling side and the transmission cooling side of the radiator goes bad, transmission fluid is usually forced into the radiator. It is unlikely that the transmission fluid actually gets into the engine oil in this matter. However if it were to get into the engine oil, it would be mixed with some engine coolant, thus producing a murky look to the engine oil. It is also unusual for engine oil and transmission oil to mix under those circumstances.
We are here to sell engines as a way to make a living, however we don’t want to sell a rebuilt engine to someone who does not need one. The value of knowing who to deal with when you have an engine issue is priceless if you are getting faulty information, and pay a lot of money for something you did not need. This is the pimary reason for our GotEngines.com Blog. Good luck and Enjoy.
