# Eco transmission blew up



## mRahmani (Oct 27, 2014)

Just curious if anybody had seen a similar failure. This is a 2011 Eco with the manual, 210,000 miles. Original clutch still felt great and the transmission still shifts well (at least going up and down the driveway.) Somehow blew a hole in the side of the case.

Anybody seen a similar failure before? Any ideas on what went wrong here?


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## plano-doug (Jul 1, 2015)

mRahmani said:


> Just curious if anybody had seen a similar failure. This is a 2011 Eco with the manual, 210,000 miles. Original clutch still felt great and the transmission still shifts well (at least going up and down the driveway.) Somehow blew a hole in the side of the case.
> 
> Anybody seen a similar failure before? Any ideas on what went wrong here?
> <snip pics>


It's hard to tell from the pics - is the shiny round piece - shaft? - sticking out far enough to have helped break the piece off? 

How did you find the broken piece? Hanging by a thread?

I wonder if something externally hit it and cracked it. 

For a fix, I'm thinking JB Weld  Seriously, I wonder if it could be welded back on there without dropping the tranny. It doesn't have to be pretty - just sealed.

Doug

.


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## WillL84 (Aug 5, 2019)

Judging by the broken off piece it looked like the end on that shaft had been hitting for a while. Pretty sure there's not supposed to be contract there. You might have bigger problems


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## mRahmani (Oct 27, 2014)

Oh, I'm sure the trans is toast. The shaft pretty clearly made contact with the case and moved enough to punch through it. There's also bearing rollers scattered all around the frame rail underneath (which is where I found the piece of the casing too.) I'm mostly wondering why something like that would happen. I can still shift into gear smoothly with no grinding.


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## mRahmani (Oct 27, 2014)

Looking at this picture, looks like the offending part is the input shaft (18). Wonder what allowed it to move enough to contact that case. It has enough play right now for me to move it by hand.


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## WillL84 (Aug 5, 2019)

I almost want to say it looks like #16 rather than #18. The bearing is what centers that shaft in the case and typically handles whatever (usually light) axial loads as well. Something's definitely not right if it popped through like that though. Probably a defect when it was made but it's been so long at this point they surely won't do anything.

If it is #16 I'd be looking at some kind of linkage misadjustment putting too much side load on the shift forks and subsequently the bearing and case.


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## mRahmani (Oct 27, 2014)

You're right, it is 16 and not 18. That's labelled as "shaft, main lower" on the diagram.


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## WillL84 (Aug 5, 2019)

Been slamming those shifts really hard? That's the only thing I could see outside of an improper adjustment that would shove the shaft into the case like that. Unlikely alternatives could be a bad cover casting where the face or bearing pocket got machined just slightly out of spec height-wise and was putting too much pressure on the cover or maybe a slightly too-long shaft that was doing the same. It wasn't much extra clearly as it took over 200k miles to break.

Interesting failure either way and we'll probably never know the exact cause which is unfortunate.


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## mRahmani (Oct 27, 2014)

I drive "enthusiastically" but don't beat on the transmission very hard; it's not exactly a fun gearbox to slam shifts through. I have a Trans Am for that.

Since I'm replacing this unit, has anybody tried swapping gearsets between the MF3 in the Eco and the MR5 in the LT cars? It would be really nice to have the shorter LT gears for around town and keep 5th and 6th from the Eco for my long highway commute. I think this would be straightforward part swapping and a flash for the speedometer but would love to hear if anybody else on the forum has tried something similar.


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