Gearshift rattle - Any suggestions?

[Wolverine]

I've owned my '76 4-speed Vette for about a month. I am noticing a rattle due to vibrations in my gearshift and it gets just loud enough to be annoying. It only starts rattling when I get to 70 MPH. The noise stops if I hold on to the gearshift, but that's not much fun when I'm flying down the road.

Does anyone have a clue what the problem is that would cause this? Is it a common problem? Is it something I should be worried about? (I'm almost afraid to ask)

Your suggestions are really appreciated. I'm not sure where to start - I'm not terribly mechanical, but I'm learning.

Wolverine

 

[ssvett]

There are springs in and on the shifter that will keep the biggest of rattles out. They may be broken or missing. It is somthing that will, for the most part, just be anoying. There are some comanys out there who will rebuld the shifter for around $150.00. I send mine to Volunteer Products in TN. Hope this helps.........Steve

 

[Wolverine]

Thanks, Steve - this doesn't sound too bad! At least I won't worry as much about something breaking on my first road trip next weekend.

 

[Ken]

Corvette Fever has an article in the new issue on how to rebuild your shifter.

 

[redmist]

Pre-total rebuild when I bought mine I had this same problem big time. During the teardown I found out several things. Unbalanced driveshafts and trashed u-joint. Fixed these and all I hear are the secondaries kicking in. No vibration

 

[Wolverine]

Redmist,

Thanks for the advice. The rattle stops if I place my hand on the gearshift & it doesn't feel like a serious vibration.

When I bought the car, my mechanic put it up on a rack for inspection and the u-joints & everything else seemed to look pretty good. How would I know if I had unbalanced driveshafts? By the way, what does that mean?

Wolverine

 

[redmist]

Similarly mine would also stop when I put my hand on the knob.
Regarding the driveshafts, check to make sure there is not any undercoating blobs, mud etc. Secondly you should see a peice of metal (approximately 1/4 inch by 3/4 or some times a regular washer) spot welded to the shaft. If not, this could indicate that it has fallen off. It is possible that yours did not require a balancing weight but most of them have them.
It is a pretty simple process to remove the shaft and inexpensive to have it balanced just to be sure. At the same time pull the rear transmission yoke. (It pulls right out once you have removed the driveshaft) and check to see if there is any irregular wear on the outside of the shaft. This could also indicate a problem.
Hope this helps.