tranny on E85 fill plug

[wolfman13]

Maybe I was just posting on wrong section of forum so here goes.
Since I took car on a 3+k trip the tranny has started to gurgle in drive and reverse while idling. I jacked up said car and inspection/fill plug is corroded tight and the center is rounded out somewhat! I have tried liquid wrench, some moderate heat, plus trying to jar it free with a small chisel on the edge of the plug - all to no avail!!! Anyone run into this before that got it freed up? You would think an Engineer would know that 2 dissimilar metals fastened together for 10 years MIGHT create a problem down the road. Have they never heard of Anti-seize?

[skippermccoy]

Try using 50% acetone and 50% ATF in a spray bottle. Spray it tap it with a mallet and spray it again let it sit and repeat as needed. that has worked best for me over the years. It was an old military trick a friend of mine told me about.

[wolfman13]

Finally got the fill plug out (thanks for the tip on the acetone/atf mixture) but that is too low to actually be the fill hole - its just above the pan on the driver's side rear of the tranny and when I got it out I also had about 2 qts of nasty dark gray (really watery) fluid come out. The drain plug is frozen as well as one of the small pan bolts! What a PITA!!! Is the inspection/fill plug higher up in the rear passenger's side back of the tranny? I can kind of feel what appears to be the same type of fill plug there. There is no way 7 qts are going to fit in there with the hole so low!

[GuidoK]

I think 7qts is generally the amount that sits in the whole of the system, so including the torque converter, pipework, cooler etc.

What you want is a complete flush. For that most mechanics use special equipment, but you can do it by disconnecting 1 hose to the cooler and briefly crank the engine, top up (1/2 qrt or so), crank again, top up again etc etc. (on the z4 the transmission oil cooler is a heat exchanger on the radiator)

Like this (this guy does it continiously but be sure the transmission doesnt run too dry!)

Lots of videos on youtube on this topic.
You probably need 1,5x the total amount of fluid in your system to do a good flush.

[wolfman13]

Just where is the fill plug on the '03 z4 with the 5speed steptronic ? I removed one from the side but it is less than an inch above the shallow pan! There has to be one higher up. I can feel what might be it on the rear of the housing that appears to be a plug but need clarification first. I will just try a google search for the location since the Haynes Manuals for this car are even less informative than they were for my '88 Jag.

[wolfman13]

Just wondering here, about how thick is the atf supposed to be? The stuff I got out from removing the fill plug was dark gray and had the consistency of 10w oil. It still had a decent amount of "slickness" to it but it just didn't look right.
I guess that after reading a few more posts that the fill plug is the one just above the pan. I will have to re-read the steps a few times before changing the filter. I still haven't got the drain plug free (will do that once it is off the vehicle) plus one of the pan screws is being a PITA but then what else should be expected after 11 years of use?!

[wolfman13]

Well, finally got the holdout freed. One of the machine screws on the pan needed a small chisel to nudge it free (about 45 minutes worth of tapping it around so that it finally let loose with only 2 turns left to go!). Now just waiting for the filter to arrive. I will go to the local hardware store and see if they have a comparable metric machine screw. BTDT, just need a hardened one for the application.
Thanks to all who assisted here so far.

[papak]

The trick I used to get out all those bolts holding the pan was to spray Liquid Wrench on the top side of the pan lip. On my E86, all of those bolt holes are open on the top side. Spray them all and let it sit for an hour or two (I waited overnight). They all came right out with no problem.