The shifter in my Chevelle vibrates pretty bad at higher speeds (80 + )

The car handles fine and otherwise seems pretty normal. The only other thing at all that I notice vibrating is the rear view mirror on the windshield.

What would likely cause this vibration?

The car has a newly rebuilit 454, muncie 4 speed M21, a newly rebuilt hurst shifter, and a 12-bolt rear-end.

The entire drive train and suspension was replaced and/or rebuilt by the person who sold me the car.

I am going to take it to a mechanic for a thorough inspection, but I thought I'd see if you guys have any ideas?

Randy

The shifter in my Chevelle vibrates pretty bad at higher speeds (80 + )

The car handles fine and otherwise seems pretty normal. The only other thing at all that I notice vibrating is the rear view mirror on the windshield.

What would likely cause this vibration?



Lots of power :D

What RPM are you turning at 80? My whole car shakes at pretty much all times, but thats half the fun of having a BBC and a 4-speed. I don't think anything is wrong. If the rear view shakes, it's just the vibration of the motor being transferred through the drive line.

Chris

Chris wrote:

What RPM are you turning at 80

It think it was around 3500, but I really wasn't paying attention to the tach.

I don't think anything is wrong.

Maybe nothing is wrong, but the shifter rattle is pretty severe IHO. However, I haven't driven a big block 4 speed in two decades, so I don't recall what it's supposed to be like.

It (the rattle) seems excessive to me.

Randy

It think it was around 3500, but I really wasn't paying attention to the tach.



You must have a fairly high rear then.


Maybe nothing is wrong, but the shifter rattle is pretty severe IHO. However, I haven't driven a big block 4 speed in two decades, so I don't recall what it's supposed to be like.

It (the rattle) seems excessive to me.



Everyone's got their preference. Little things like that don't bother me. ALl I know is mine rattles a lot. And by a lot, I mean, it's audible over the engine (as long as the headers aren't open) and you can see it shaking as where going down the road.

Chris

Rear end is 373.

randy, my 69 SS396's Hurst shifter rattles at anything higher than 60mph under hard acceleration. it's just normal in my opinion.

Driveshaft maybe.

Oh yeah, hard launches will start twisting the axles, I had one that started tossing spider gears.

2cool wrote:

Driveshaft maybe.

What could be wrong with the driveshaft and can it be repaired?

2cool wrote:



What could be wrong with the driveshaft and can it be repaired?

Balancing, check my axle post above too.

Theres just so many things it could be, has the car sat for a long time? may have flat spots on the tires and so on.

it could be out of balance and yes you can get it balanced. You also might want to check your pinion angle. Since you only have the vibration at higher speeds this doesnt indicate an engine related vibration, otherwise you'd have it in all gears at a given rpm. (assuming this vibration isnt the normal deal that everyone is talking about). Do you know if you have adj. upper control arms>?

2cool wrote:

Theres just so many things it could be, has the car sat for a long time? may have flat spots on the tires and so on.


No. The tires are brand new. The car did sit while it was being rebuit. I'm not sure exactly how long the rebuild took. I know that the guy who sold it to me only had it for two years and he's the one the rebuilt the drivetrain and suspension.

bdc1013 wote:

Do you know if you have adj. upper control arms>?


I don't know off the top of my head. I'll look into it.

The guy who sold it to me gave me all of his records. So I can look it up.

or you could just look under the car at the upper control arms and you'll be able to tell if they are adjustable or not... hey even better if you snap a picture of them we could tell what they are and if they are adjustable. If they are solid you might want to look into some edelbrock adj. uppers. I sure theres more companies that make them but i have the edelbrock ones.

My 67 has what appears to be a naturally occuring vibration above 70. I have replaced everything and it now has Edelbrock adjustable upper control arms. The vibration is still there. It's minor but I can feel it at 71 MPH and above. It has been suggested that the early Chevelles may have been built with a lower resonance point, meaning that when the running gear is spun up it becomes resonant at a certain speed (the strobe light principal). If you have tall gears you will make the running gear spin even faster from the tranny output to the rear end, including the rear gears. I have a Tremec overdrive and 3.73s and I feel it. brian, who just responded, has the same tranny and doesn't feel it in the later models. I never felt it when I had 3.55 gears. I think the tall gears put it into the virbo-zone.

First, before you spend a ton of dough, do a search on "vibration" and one on "pinion angle". There are lots of posts. This is not new. Secondly, if you figure out what it is, send me an email

Good luck
Chuck

check for tailshaft wear

check for tailshaft wear

If thats worn the pilot shaft bushing is probably shot as well.

Solid motor mounts?
Mine does the same thing and I just figure that it is normal for these types of cars.

Ya, solid motor mounts is what I was thinking also. Have you tried getting up to 80 or so an pushing the clutch padel down after you decelerate?, are you running headers? they could be rubbing somewhere.

My 69 didnt vibrate at all, at any speed, My 66 has its problems with vibrations and alot of it.

My shifter had bad vibration also. I changed to a new transmission mount and most of the vibration disappeared.Check the engine mounts too,they can be a source of vibration also.

now that everyone has chimed in, and i think about it, it could be many many things. i.e Pilot bearing, driveshaft, u-joints, pinion angle, flywheel/clutch balance, mounts (engine/trans), bellhousing allignment, wheels, tires, brakes, and so on. Vibrations suck. Is it the kind of vibration that wants to shake the radio out of the dash or is the kind of vibration that you'll say to someone "do you feel that?" ?

chuck what kind of driveshaft are you running and what size? I've heard that a 3 to 3.5 inch carbon fiber driveshaft could help you out on your vibes above 71 mph... might want to look into it.

Brian wrote:

Is it the kind of vibration that wants to shake the radio out of the dash or is the kind of vibration that you'll say to someone "do you feel that?" ?



It's somewhere betweem the two. Anyone in the car would hear the rattle and see the shifter shaking. It's more of a hear and see than a feel vibration.

Sounds like it could be many things. I'll have my mechanic look into it, once I find one.

Jim wrote:

Have you tried getting up to 80 or so an pushing the clutch padel down after you decelerate?,

No, why?

are you running headers?

Yes. I'll add that to my list of things to check. ;)

Brian wrote:

Do you know if you have adj. upper control arms>?


I looked at the rear suspenion. The control arms don't look adjustabe to me.

well here's what im talking about. they allow you to adj. the pinion angle.

http://store.summitracing.com/partdetail.asp?autofilter=1&part=EDL%2D5249&N=700+4294908216+4294908021+4294925084+115&autoview=sku

chuck has them and has his pinion angle dialed in and still has the vibration, but hey they cant hurt!

My 66 used to do the same thing. I did several thing to correct the problem.
1. I had the shifter rebuilt, waste of money i would buy a new one.
2. I was using a truck bellhousing and I installed the bushing on the retainer bearing.
3. The balancer on my 350 was either "clocked "incorrectly or starting to slip, so it was replaced.

Now even at 100+ no vibrations.

bdc1013 wote:



I don't know off the top of my head. I'll look into it.

The guy who sold it to me gave me all of his records. So I can look it up.


I think the only way to determine what the problem is to let me drive it. :D

Then we could go from there. :)