1987 Corvette manual 4+3 shifter and transmission issue
05-26-2019, 07:30 PM
#1
1st Gear
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1987 Corvette manual 4+3 shifter and transmission issue
Hello everyone and thank you for your time.
I've recently rebuilt my corvettes engine all the way down to the clutch, I've installed a new throwout bearing and pilot bearing as well as a new clutch fork. I have no leaks in the slave cylinder and the clutch goes through all the gears easy with the engine off and On. The only issue I had before I pulled the engine was my reverse making a whirling noise but not moving me anywhere. So I researched and
I believe it is because I have a bad OD unit.
Which brings me to the issues.
My OD was acting up so I decided to change the relays, drained the pan, cleaned the pan, and replaced the gaskets I then sealed it with rtv and no more leaks. Of course the fluid that came out looked more like motor oil than ATF. So there was a lot of my problem or so I thought. (Magnet was also fairly clean)
So then while I was down there I noticed my linkage cover was leaking to, so I got into it and decided to change the shifter forks out for new ones. I then put everything back sealed it and again everything seemed to work fine.
The car goes into all the gears but the ISSUES NOW ARE
1. No deceleration upon downshifting.
It just feels like it coasts.
2. When I downshift into 1st gear I can feel as if there was something hitting the shifter from underneath.
Along with a tapping noise.
My question is. Is this due to something I did with the shifter forks, or is this all attributed to the bad OD Unit??
Can I replace the OD unit without taking the whole transmission out ?
Thank you so much for reading. This is my first actual vehicle project and I'm learning a whole lot.
I've recently rebuilt my corvettes engine all the way down to the clutch, I've installed a new throwout bearing and pilot bearing as well as a new clutch fork. I have no leaks in the slave cylinder and the clutch goes through all the gears easy with the engine off and On. The only issue I had before I pulled the engine was my reverse making a whirling noise but not moving me anywhere. So I researched and
I believe it is because I have a bad OD unit.
Which brings me to the issues.
My OD was acting up so I decided to change the relays, drained the pan, cleaned the pan, and replaced the gaskets I then sealed it with rtv and no more leaks. Of course the fluid that came out looked more like motor oil than ATF. So there was a lot of my problem or so I thought. (Magnet was also fairly clean)
So then while I was down there I noticed my linkage cover was leaking to, so I got into it and decided to change the shifter forks out for new ones. I then put everything back sealed it and again everything seemed to work fine.
The car goes into all the gears but the ISSUES NOW ARE
1. No deceleration upon downshifting.
It just feels like it coasts.
2. When I downshift into 1st gear I can feel as if there was something hitting the shifter from underneath.
Along with a tapping noise.
My question is. Is this due to something I did with the shifter forks, or is this all attributed to the bad OD Unit??
Can I replace the OD unit without taking the whole transmission out ?
Thank you so much for reading. This is my first actual vehicle project and I'm learning a whole lot.
07-19-2020, 08:34 PM
#2
A free Wheeling Doug Nash $4+3 when coasting downhill, The OD is more than likely the problem.
Was the OD working properly prior to the engine rebuild ?
Did you split the case on the Trans and remove the OD unit ?
Smell and Feel of the OD fluid, was is thicker the Automatic Trans Fluid and smell some like gear oil ?
If so the seal between the OD and Trans is leaking. Rebuild time.
Michael..
Was the OD working properly prior to the engine rebuild ?
Did you split the case on the Trans and remove the OD unit ?
Smell and Feel of the OD fluid, was is thicker the Automatic Trans Fluid and smell some like gear oil ?
If so the seal between the OD and Trans is leaking. Rebuild time.
Michael..
07-20-2020, 11:52 PM
#3
Le Mans Master
4+3
You messed up with the forks, putting the cover plate back on.
take it back off, look at the bolt holes on the cover, line up the groove On the synchro according to the holes, slide it on.
i have a 4+3 in my 57 chevy truck, and changed the overdrive, its easy to misalign the cover.
take it back off, look at the bolt holes on the cover, line up the groove On the synchro according to the holes, slide it on.
i have a 4+3 in my 57 chevy truck, and changed the overdrive, its easy to misalign the cover.
Last edited by coupeguy2001; 07-20-2020 at 11:53 PM.