Transmission whoops
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Cruising
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Transmission whoops
So.....I was traveling down the interstate around 70mph and the rear end locks up for just a split second and then everything was fine. I got to where I was going and turns out that lock up was something to do with reverse. I no longer have reverse gear but all forward gears work just fine. I would assume this now has fragmented parts inside the transmission so should not be driven. well.... I got to drive a corvette for 7 days. Not horrible. I planned on dropping the entire drive train out and replacing everything anyway.....just not immediately. anyway on to the point. Am I wrong to assume it should not be driven? (I did go about 4-5 miles after it happened just to get home) anyone have any idea what caused this?
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Cruising
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That was my guess. figured there are parts of the reverse setup sitting down in the trans. if they somehow worked their way up it would be terrible. slowly finding more and more issues with this car and seeing why I got such a great deal. Oh well been waiting 16 years for a corvette. I will have this thing back on the road.
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Odd failure. You sure it wasn't the TC or AH applying rear brakes for a second?
The transmission is fairly tight inside. If metal parts are rolling around inside then it's likely completely trashed by now. More likely, you broke something in the shifting mechanism then reverse gear engaging and breaking while you were driving in 6th gear. Unless you're not telling the whole story and you smashed it into reverse very hard trying to get to 5th....
The transmission is fairly tight inside. If metal parts are rolling around inside then it's likely completely trashed by now. More likely, you broke something in the shifting mechanism then reverse gear engaging and breaking while you were driving in 6th gear. Unless you're not telling the whole story and you smashed it into reverse very hard trying to get to 5th....
Thread Starter
Cruising
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Odd failure. You sure it wasn't the TC or AH applying rear brakes for a second?
The transmission is fairly tight inside. If metal parts are rolling around inside then it's likely completely trashed by now. More likely, you broke something in the shifting mechanism then reverse gear engaging and breaking while you were driving in 6th gear. Unless you're not telling the whole story and you smashed it into reverse very hard trying to get to 5th....
The transmission is fairly tight inside. If metal parts are rolling around inside then it's likely completely trashed by now. More likely, you broke something in the shifting mechanism then reverse gear engaging and breaking while you were driving in 6th gear. Unless you're not telling the whole story and you smashed it into reverse very hard trying to get to 5th....
no I had it at 70 in 5th, cruise control engaged just rolling down the interstate. reverse had been sketchy since I got it. had assumed it was just out of alignment and had planned to do the adjustment today. however with a full on reverse failure I need to jack it up and see if anything looks weird under there. as far as TC or AH I highly doubt it because as I said I had cruise control on.
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There's so little free space in there. Anything loose is going to get sucked up and thrashed around regardless. But if that indeed were happening, I'd expect some pretty significant NVH increase. I wonder if maybe you just lost a linkage that allowed the reverse idler to nick the shaft gears ever so briefly? When you try to shift into reverse, does it feel like the shifter is still trying to move something in the transmission, or is it just loose/floppy in that position?
Last edited by wcsinx; Apr 3, 2019 at 05:37 PM.
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This ^
There's so little free space in there. Anything loose is going to get sucked up and thrashed around regardless. But if that indeed were happening, I'd expect some pretty significant NVH increase. I wonder if maybe you just lost a linkage that allowed the reverse idler to nick the shaft gears ever so briefly? When you try to shift into reverse, does it feel like the shifter is still trying to move something in the transmission, or is it just loose/floppy in that position?
There's so little free space in there. Anything loose is going to get sucked up and thrashed around regardless. But if that indeed were happening, I'd expect some pretty significant NVH increase. I wonder if maybe you just lost a linkage that allowed the reverse idler to nick the shaft gears ever so briefly? When you try to shift into reverse, does it feel like the shifter is still trying to move something in the transmission, or is it just loose/floppy in that position?
Team Owner
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Yeah, my theory then is you lost the reverse linkage, and the thump you felt was the idler gear trying to engage. Maybe if you're lucky, the gear isn't damaged too badly. The fact that you're still driveable without any other apparent symptoms would seem to indicate that there aren't big chunks of idler gear floating around your tranny.
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Thread Starter
Cruising
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Yeah, my theory then is you lost the reverse linkage, and the thump you felt was the idler gear trying to engage. Maybe if you're lucky, the gear isn't damaged too badly. The fact that you're still driveable without any other apparent symptoms would seem to indicate that there aren't big chunks of idler gear floating around your tranny.
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From: South Western Ontario
All the linkages are inside the transmission. I doubt it was a gear moving around, because gears don't move around to engage and disengage. Synchronizing sliders put it in and out of gear, but they generally don't just move around on their own since they are keys that hold them in the neutral position.
It's not a transaxle. It's a separate transmission and differential, they are just bolted together.
It's not a transaxle. It's a separate transmission and differential, they are just bolted together.
Team Owner
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so potentially put the linkage back together and all is well. again I planned on putting all new drive train into it anyway, but If I can put it back together and few a few months out of it as is I would be thrilled...... now to educate myself on how to do this (never had a transaxle before) thank you very much for the info.
All the linkages are inside the transmission. I doubt it was a gear moving around, because gears don't move around to engage and disengage. Synchronizing sliders put it in and out of gear, but they generally don't just move around on their own since they are keys that hold them in the neutral position.
It's the difference between this (for example, yes I know that's not a T56) where reverse shares a dog clutch with 5th and the idler is always engaged.
and this where the reverse idler is engaged and disengaged via its own linkage (for example, yes I know that's not a T56)
And in both pictures above, you can think of each dog clutch representing a vertical line in the shift pattern.
Last edited by wcsinx; Apr 4, 2019 at 09:30 AM.
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Yes, you are wrong. The T56 revere gear uses a synchronizer the same as the other gears.
If you've never been inside one, then you could have searched the internet for pictures of the actual T56 reverse synchronizer instead of some useless generic pictures....
If you've never been inside one, then you could have searched the internet for pictures of the actual T56 reverse synchronizer instead of some useless generic pictures....
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If you've never been inside one, then you could have searched the internet for pictures of the actual T56 reverse synchronizer instead of some useless generic pictures....
Drifting
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From: Buffalo NY
Back on topic: here's a thread I posted a couple years ago documenting my T56 teardown. Hope it helps.
https://www.corvetteforum.com/forums...age-trans.html
https://www.corvetteforum.com/forums...age-trans.html
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Don't go on now any further about how your true claim was really that the shift fork wasn't shared between reverse and a forward gear instead of the claim reverse was a floating sliding gear that could move around if the fork became disconnected.
5 seconds of Googling found this thread with good pictures of the reverse synchronizer with no moving gear.
https://www.thirdgen.org/forums/tran...6-reverse.html
Last edited by lionelhutz; Apr 4, 2019 at 02:57 PM.
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At least I don't keep changing my claims trying to defend a wrong position. You first posted that it was a sliding gear that could move around if the shift linkage disconnected from the reverse fork and then made a point of further posting wrong pictures and crap about how the transmission would be with a sliding gear and not a synchronizer for reverse.
5 seconds of Googling found this thread with good pictures of the reverse synchronizer with no moving gear.
https://www.thirdgen.org/forums/tran...6-reverse.html
https://www.thirdgen.org/forums/tran...6-reverse.html
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https://community.cartalk.com/t/manu...nizer/92319/20
"Some manual transmissions use a sliding idler gear to engage reverse, some use a synchronizer."
...with multiple explanations of how traditionally a reverse gear doesn't have a fully featured synchronizer (as in with a blocking ring / synchro / synchromesh) unless it's being shared with a forward gear. Perhaps the T56 is different and does indeed use a fully synchronized dog clutch on reverse. I don't know.
Now go ahead and completely misinterpret this post and explain to me that the guys in that thread aren't specifically talking about the T56 even though I just said as much.
Last edited by wcsinx; Apr 4, 2019 at 04:08 PM.
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Yes, you had to make a big post about how I was wrong....
What part of "good pictures of the reverse synchronizer with no moving gear." is confusing you? The pictures show the reverse synchronizer, ONE EVEN HAS A LABEL POINTING TO IT.
I really DGAF about your new link. Is that an attempt to prove you're right about some other transmission or something like that?
Name calling - the last bastion of the ignorant trying to prove "some" point.
I really DGAF about your new link. Is that an attempt to prove you're right about some other transmission or something like that?
Name calling - the last bastion of the ignorant trying to prove "some" point.
Last edited by lionelhutz; Apr 4, 2019 at 04:25 PM.
Team Owner
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So you offered up a picture of a reverse synchronizer as proof that it took you "5 seconds of Googling" to find "clear T56 exploded views". mmmkay
A gear is not a transmission just FYI.
I really DGAF about your new link. Is that an attempt to prove you're right about some other transmission or something like that?
Of course you don't GAF about it because it disagrees with you. You seemed to take issue with my claim that many transmissions do indeed use a sliding idler gear to engage reverse. Your exact words were, "the claim reverse was a floating sliding gear that could move around if the fork became disconnected" Does the T56? Again, I never claimed to know having never torn down a T56. And somehow it feels like I'm talking to someone who has never had the pleasure of having any transmission in pieces on his workbench judging by how you continually confuse terminologies.
And honestly, the only point of all my prior exposition was to demonstrate how the T56 can indeed engage reverse while in any forward gear if the linkages are compromised. And I really don't give a **** if you believe me or not.
Name calling - the last bastion of the ignorant trying to prove "some" point.
Last edited by wcsinx; Apr 4, 2019 at 05:17 PM.
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Now I have to point out that THIS IS A THREAD ABOUT A T56 TRANSMISSION. Why would I be writing anything here about other transmissions? Called it.
Once again, it's technically possible for more than one gear to engage at a time in ANY transmission with more that 1 slider or shift fork (or basically every manual transmission put into a car). That is not an issue unique to a transmission with a dedicated reverse shift fork (be it moving a slider or a gear). Years ago I used to quite regularly have to pull the linkages on the old 3-speed I was driving to get it out of the 2 gears it was stuck in at the same time. The reverse fork was shared with one of the forward gears.
As I wrote way back, the sliders don't generally move on their own. If you've been inside a transmission, then you'd know how they take a decent force to get them to move off center or out of the neutral position. So, I still don't believe reverse tried to engage. It's more likely a piece came loose and went through one or more of the gear sets.
For the record, I've been inside a T56. Even got a bunch of parts in a bin in the basement. I've got the proof of what the gears look like after a piece of metal gets loose inside one. Hope you still fell smug about that comment though.
Last edited by lionelhutz; Apr 4, 2019 at 06:52 PM.