87 Vert w/Automatic transmission

[Jeb]

Since I've owned this car, the transmission shifts have been rather abrupt and not smooth as I was accustomed to in other cars. On most shifts, when it shifts, there is an audible click or snap. It happens on shifts from 1-2-3 upshifting and I notice it when the transmission shifts back to 1st when stopping.

I'm pretty sure the noise is coming from the transmission but it could very well be the differential. It is NOT the U-joints.

I figure that before I start losing sleep over this after 3 years of owning the car, I might want to find out if (a) it's normal for this transmission, or (b) there is an easy and quick fix for it if it isn't normal.

Any ideas? :W

 

[boomdriver]

Since I've owned this car, the transmission shifts have been rather abrupt and not smooth as I was accustomed to in other cars. On most shifts, when it shifts, there is an audible click or snap. It happens on shifts from 1-2-3 upshifting and I notice it when the transmission shifts back to 1st when stopping.

I'm pretty sure the noise is coming from the transmission but it could very well be the differential. It is NOT the U-joints.

I figure that before I start losing sleep over this after 3 years of owning the car, I might want to find out if (a) it's normal for this transmission, or (b) there is an easy and quick fix for it if it isn't normal.

Any ideas? :W

Might want to adjust the trans throttle cable. Might be set too hard/tight. Its a personal preference where to set the trans in a C-4.

 

[vetteboy86]

There is a huge difference in the firmness of shifts based on the TV cable. It possible for the shifts to go from lazy and feel like pooh, to a snappy firm shift. As suggested the cable adjustment would change the firmness of your shift. As to your noise, it's hard to say. The C4 is creaky animal anyways. Keep in mind that an incorrectly adjusted cable can toast the tranny pretty quickly. I wouldn't adjust yours more than 1 or two teeth. To soften shifts, move the cable sheath towards the front of the car.

 

[vetteoz]

Its a personal preference where to set the trans in a C-4.

Common misconception
Yes you can do it but TV cable is not there to adjust shifts for your comfort
There is only one correct position for the TV cable
Notice the wording

[FONT=Arial, Helvetica, sans-serif] We are not aware of a single GM publication that advocates "adjusting" the TV cable once it has been properly "set".[/FONT]

see
Bowtie Overdrives | TV Made EZ

 

[Jeb]

Thanks for the information. I'll take a peek at the adjustment and make sure it's on target.

Again...thanks a bunch. I don't post here much but I read the stuff you guys write and it's a great place for information. I've saved both a lot of money and hair by reading here.

 

[boomdriver]

Common misconception
Yes you can do it but TV cable is not there to adjust shifts for your comfort
There is only one correct position for the TV cable
Notice the wording

[FONT=Arial, Helvetica, sans-serif]We are not aware of a single GM publication that advocates "adjusting" the TV cable once it has been properly "set".[/FONT]

see
Bowtie Overdrives | TV Made EZ

True I'm sure. Its NOT a performance tuning tool...

But, people DO seem to like the ability to set poo soft early upshifts, or others like the more aggessive long delayed upshift way past its natural point. As long as the trans is not driven low speed in OD, the TCC let the driver shift manually 1-3 with the same positive feel of a stick.

 

[vetteoz]

the TCC let the driver shift manually 1-3 with the same positive feel of a stick.

Please explain?
TCC only locks the convertor; has nothing to do with shifts

 

[vetteoz]

On most shifts, when it shifts, there is an audible click or snap. It happens on shifts from 1-2-3 upshifting and I notice it when the transmission shifts back to 1st when stopping.
I'm pretty sure the noise is coming from the transmission but it could very well be the differential. It is NOT the U-joints.

Put rear of car up on jackstands chock front wheels and get someone to run it up and down through the gears while you look / hear underneath.
Could be many things, play in the diff , loose C Beam bolts ,worn hub
How do you know it is not one of the six U joints?

 

[boomdriver]

Please explain?
TCC only locks the convertor; has nothing to do with shifts

You're right...
I was trying to explain the "feel" of what TCC does by locking in the TC and having that engine braking or positive accelleration. Manual upshift is still up to the driver BUT, even that can be effected by having the TV cable too tight.

 

[Jeb]

Put rear of car up on jackstands chock front wheels and get someone to run it up and down through the gears while you look / hear underneath.
Could be many things, play in the diff , loose C Beam bolts ,worn hub
How do you know it is not one of the six U joints?

The U-joints were all checked and are fine. I was wondering about play in the diff which I believe I noted in my original post. The hubs have all undergone replacement also. This noise/click has been there since I've had the car...about 4-5 years and I'm just getting around to wondering about it - there were more important things first and it hasn't gotten any worse nor has it affected drivability. I'll see about checking the diff and making sure the TV cable is proper.

Thanks.

 

[Jeb]

You're right...
I was trying to explain the "feel" of what TCC does by locking in the TC and having that engine braking or positive accelleration. Manual upshift is still up to the driver BUT, even that can be effected by having the TV cable too tight.

Oh. One more thing. I am 65 years old, disabled, and not about to lay under anything, much less a car.

 

[boomdriver]

Oh. One more thing. I am 65 years old, disabled, and not about to lay under anything, much less a car.

Understood,
I'm right behind you. Fortunately the TV cable is adjusted under the hood on the throttle body. Much easier than crawling under...then again, at this age bending over working can be almost as challenging...

 

[Jeb]

Understood,
I'm right behind you. Fortunately the TV cable is adjusted under the hood on the throttle body. Much easier than crawling under...then again, at this age bending over working can be almost as challenging...

Oh. I can do that. I was thinking more about getting under it while it was on jack stands.