Hi,

As the title suggest, I was trying to do a trans fluid flush on a 2014 MCS. It's never been done on this car to my knowledge. I watched the videos suggesting to always attempt the fill plug before the drain plug and thats where this journey ended.
I tried with an 18" breaker bar and a hammer. Nothing. I tried with the latest Dewalt Cordless Impact (450ft lbs, tears off lug nuts like nothing) and it didnt even budge, the hex bit just got very warm.
Are they supposed to be this impossible to remove??
Im afraid if I try anything more intense the plug will get stripped and I'll have a bigger problem on my hands.
Anyone dealt with this before?

 

I would definitely be careful with this as stripping the plug will not end well.

Hey ​​​​@TVPostSound you were one of the folks to offer good advice on this business of making sure the upper drain plug was removable before getting on with trying to do the drain-and-fill. Any suggestions for unsticking this plug, for the folks who have it stuck?

@2014MCS_Miami random thought here -- I did a bunch of research on penetrating oils last year -- one interesting option, which was reported by at least one party doing side-by-side testing as solidly outperforming penetrating oil product, was a 50/50 mix of acetone and ATF, I think. If it looks like you're going to have to go there, I would keep that as a final option pending further advice in this thread. But it might be a go-to given the very small (compared to the quantity of ATF in the transmission) amount of non-ATF in the mix.

 

After hours of internet research to find a way to remove, including much reading on "Bob is the oil guy", it turns out these plugs are supposedly immersed in oil already so penetrating oil wont work on them.
Things that were recommended:
1. Hit the plug hard with a hammer several times to break the seized threads
2. Use biggest breaker bar you can get on there
3. Use floor jack to turn the ratchet or breaker bar with much more force
4. apply heat via blow torch

1-3 seem like they can cause severe damage. #4 seems somewhat logical but I dont own a blow torch and am not familiar with using them properly. I called my BMW mechanic and he basically said, "why are changing the lifetime fluid? it just creates more issues if you do that, leave it alone". So, I guess I cant go to him to have the service done there. lol.

 

I really want to know you use a floor jack (up/down movement) to turn a ratchet/breaker bar that has to rotate in parallel plane to the ground (side to side movement)...

I wouldn't want to try to aim a blowtorch into that part of the car. Maybe it's just me

I did note that on mine, there is a pretty tactile "pop" when the plug undoes. So it definitely sticks. Not that inability to get it to budge should be considered normal, more that some of the observations you've noted line up.

I would, were it mine, be willing to give the plug some hammer taps. I would use something extension-like that would rest uniformly on the *entire* head of the plug, and then tap that using a hammer. I wouldn't go crazy with it, especially knowing the thing is aluminum, just enough to try to get some of the thread action to loosen up. And I would try penetrating oil of whatever kind I felt was most generally effective based on field test, bearing in mind that if the bottom line is that the plug is treated to resist it, worst case scenario is it neither helps nor hurts.

This could boil down to persistence (with the help of that hammering, etc). How many miles on that AT of yours?

 

It's a manual transmission. 96k miles thus far!

 

D'oh I didn't realise you had a manual! I assumed it was an AT -- my bad -- and #3 makes more sense now

On the 6-speed AISIN AT the drain plug is oriented vertically (head at top) rather than horizontally. My bad

 

Can you grab a picture of the fill plug? As others have said, maybe you just need to get a breaker bar on it.

 

Unless I'm way off in the weeds here, there ought not to be any reason you can't pump fresh fluid in from the drain plug.

Obviously you need to overfill by a small amount and move quickly to insert the drain plug. Neither of which seem insurmountable.

Manual trans generally are much less sensitive to over/under fill than slush boxes.

If I were in your shoes the above would be more appealing risking damaging the trans or burning the garage down.......

 

This sounds like a recipe for disaster….

 

Why?

Done it. No Problem.

 

Your car, so you do you. You’ll be underfilling your transmission. And while the gear oil will still coat everything in there, the cooling capacity of the gear oil will not be there, the oil will break down faster from being hotter. The hotter oil won’t lubricate as well as cooler oil. Then, you’ll have to change the oil more often because it’s breaking down faster.

I would focus on getting the right socket and long lever arm onto the fill plug. It will come off, just might take some leverage. Keep the impact off it too. Last thing you need is a stripped transmission plug.

 

a few years ago i was working on my S197 mustang and wanted to remove a pipe plug in the blocks water jacket. I worked on removing that silly plug every evening after work and just could not get it out. I even started to strip in hex shape out of the plug. I regrouped and looked at some pictures of someone else taking out the plug on a forum post and they have a swivel then the extension. I thought I was fully seated in the plug. I added the swivel to my wrench set-up and it came out like butter. Lesson learned, angle of attack is important. I kept that silly plug in my tool box as a reminder. I sure felt stupid. I had no problem removing the fill plug on my F56 but maybe my mustang lesson can help you.

Get the car up in the air safely, get under the car with the right tools and the correct angle of attack and then get off the creeper so you are on the floor. That would be my advice. It wouldn't hurt to use some penetrating fluid.

Good luck

 

UPDATE: My 24" breaker bar arrived from Amazon. I lifted the car on jack stands and went to town. The Fill bolt came out very easily, go figure. There could be two things going on here: first, the "penetrating" oil did its thing over the week that I waited for the breaker bar to arrive or, second, the breaker bar simply gave me the leverage that I needed (more than a 450ft/lb impact gun tho? dunno...).

I drained the MTF which at 96k miles was nearly black and full of grime.
I filled with new Valvoline MTF fluid recommended per many other German forums after hours of research (see link).

I filled until the fluid kept coming out of the fill opening, let it reduce to a drizzle and then placed the bolt back in. I couldn't find torque specs anywhere, so I just tightened both by feel. When I first opened the fill bolt, I noted that no fluid came out, so when refilling I assumed that I had added enough of the new fluid by overfilling and then letting it drain a bit until a light drizzle.

All in all, a messy job when you dont own a lift and reminded me of my cardinal rule: leave all fluid maintenance to the shops. Lol

 

It was the breaker bar. A plug that tight, penetrating oil will never go between the threads.

I use a floor jack handle to create an even longer breaker bar!!!!

 

I think to get an axle nut (not a MINI) off once I put a length of PVC pipe inside another length of PVC pipe around the handle of a 24" breaker bar.

That was "fun." And probably a little dangerous. But man was it satisfying when 4 full feet worth of "breaker bar" did the job on a fastener that had surely not been turned since the 1990s

 

How much for the dealer to do this???? Seems like the best option.....if it breaks off, it's on him to repair. This is something I would not screw around with, the risks FAR out weight the rewards of saving a few bucks.