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MN12 no reverse. Help needed!!

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Old 01-04-2012, 10:36 PM
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Default MN12 no reverse. Help needed!!

Car is a 2003 C5Z btw

All was well on my way to work, but when I went to back into "my" parking space, the tranny wouldn't shift into reverse. I figured it was a lockout so I turned off the car to try to put it into reverse. Still wouldn't let me into reverse with the key off... So I had to park like a normal person lol

I did some research that day about the bushing on the shifter. I had my heart set on all my woes being fixed by a simple bushing! Rolled the car out and started my 60 mile commute home. Half way through my commute, my gauges started blinking that the transmission was hot. Really hot. Like 270* hot!! I pulled over to let it cool. When it had cooled down I got back on the highway and the temps were fine, staying between 160-210. When I arrived home, my muscle memory of backing into a parking space took over and I decided to try reverse again. This time, it went all the way to the right, where reverse is supposed to be. I let the clutch out and a sick, horrible, teeth clenching rattle came out of the transmission. Turns out I can leave the clutch out and put the tranny into reverse... Ouch right??? With the car in neutral and the clutch out, the same chatter in the tranny can be heard. I tried turning the car off, putting the shifter in reverse and starting the car again but still no reverse. I've heard the tabs on the shift forks are plastic. Could this cause my problem? Either way that transmission needs to come out...But I need and would appreciate some pointers on what parts to order so I can have them on stand-by for when the transmission comes out.

Sorry about the long story, I just wanted to be very thorough. BTW the car is still bone stock, no mods to the drivetrain what-so-ever

Thanks in advance!!
Old 01-05-2012, 05:25 PM
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bad news is the trans has to come out. the good news is that your problem might only be isolated to the rear of the transmission. But I guess since youre in there you could beef it. keep us posted.
Old 01-08-2012, 01:48 PM
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There is no bushing issue with the Vette as it uses a completely different setup, with the remote shifter. It's got to be internal. We can build/upgrade the trans, starting at $800 parts/labor if you are going to send it off. Good luck
Old 01-09-2012, 09:33 PM
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Only took about four hours...Not too bad of a project.

Decided to pop the tranny open and take a look just because I'm curious like that. Bits of bearing fell out along with a couple snap rings and some very thin rings, not to mention the gobs of shavings stuck to the magnets!!!

The teeth on the main shaft look to be "ok" with no pieces missing though. We'll see...Waiting for tax $$$
Old 01-10-2012, 11:00 PM
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Looks like the rear bearing pooped itself and caused an all out self-destruction
Old 01-11-2012, 05:29 PM
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Wowzers that sucks
Old 01-11-2012, 10:02 PM
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You'll need a tailhousing, mainshaft, and a new reverse gear and some bearings, etc. So far, thats $50, $150, and $125, random small parts ---no charge
$325 so far. If you tear it the rest of the way down, maybe we can see what else is wrong. Plus it would be a little easier to UPS it over in pieces
Old 01-12-2012, 09:09 AM
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The bearing damage & the snap ring comming off( the reason the gear wanted to machine itself out the back) are due to synchronizer damage. All the struts are broken & the blocker ring is broken. Those floating pcs. are what caused the carnage.



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