Hi,

I was wondering if anyone has had an issue with their auto transmission loosing fluid but there is no leak visible? it never leaves drips even when idling underneath it. After doing some research online it seems that the diaphragm on the vacumn modulator may be not working correctly so it's sucking in trans fluid into the intake. It also has a bit of white smoke out of the exhaust and the fuel economy is terrible, could this also mean that maybe the fluid that maybe burning has contaminated the o2 sensor?

Thanks, let me know if you have any advice.

 

Thats is an interesting theory?
The ATF will not cause an O2 or HO2 to fail/ At one time running ATF into the engine oil was a way to preclean the engine before an oil and filter service.
How much are you actually measuring accurately lowering the level of the ATF? And how are you checking the ATF oil. Time of day and hopeful a well warmed up engine and transmission.
Large amount showing being loss you would be smoking out the exhaust generally almost always or at least while accelerating.

Aside from that I will let our resident members Mazda little truck experts chime in on their advice and thoughts .

 

Hi, thanks for your reply!

I need to top it up every two weeks, I'm measuring it warmed up on a flat surface and in neutral to get the best reading.

So do you think the the Vacuum modulator on the transmission is causing the ATF to leak into the intake? I tried looking for the vacuum line to check if there any ATF on it cut it looked dry but I don't know where else it would be going . That's interesting about the ATF fluid being used to clean the engine before an oil change, I was looking for a reason why the fuel economy could be bad.

I'm getting terrible fuel economy, 12 Miles per gallon (driving on the highway mainly) and I'm driving slowly everywhere, I bought the truck from a friend a month ago and he had the same issues. Checked the choke, air filter.

Thanks