Odd vibration under acceleration

[terry_b]

I've searched through a bunch of threads and I think I'm on the right track but I wanted more current input.

I've got an odd vibration that seems to come and go. Vibration usually comes in under acceleration on the highway, usually 65-75 in 5th gear. Vibration goes away on decel and while on cruise control. When it does vibrate, it feels like it's the whole car - I can feel it in the steering wheel, in the seat and on the floor. I can't pinpoint front/rear and the hardest part is that it's inconsistently there and gone.

Recently, I had a bent wheel straightened by Rimpro and a full alignment done by my shop. They did a great job, but then I've gotten this vibration.

I'm having the shop put on new brake pads and rotors and do oil, transmission and diff fluid. What should I have them check while it's on the lift?

Likely culprits look like driveline bolts, CV axles and maybe even a wheel bearing? I plan on having them check the alignment and balance the tires while they're off the car as well.

I'm at 60k miles, stock everything and I've had the 1LE struts replaced under warranty once already, what else should I be looking at replacing/servicing while the shop has it?

[jonathanmoguel]

im having the same issue any updates?

[Moto-Mojo]

Don’t forget the center (carrier) bearing on the driveshaft as a possible source.

[Stingr69]

Sounds more like a driveshaft issue or a tire. Check the bolts especially at the rear driveshaft coupler joint. Look for loose or missing bolts.

[qcman]

My car has a similar symptom to what the OP noted. If I do a hard pull on the highway (car drops a couple gears and takes off as I'm auto) I can feel some vibration in the steering wheel, its kind of up-down not side to side. It seems almost RPM based as in its more apparent at higher revs. I'm going to test it while letting go of the wheel for a second to see if there is anywhere else I can feel it. Its not tires as it stops if I lay off the gas........

It has been like this for a good 3 or 4 years. I always figured if it was a problem it would get worse but it never has. I had a minor accident in 2015 where I got my car hung up on a parking lot curb and used the cars power to pull it back off & I always wondered if I stressed something in the driveline doing that. Tires were squealing a bit to get her pulled back down. I suspect this as I noticed it only after getting the car back from the body repairs.

I had asked my dealer about it a few times but they always said they can't replicate it mind you they would have to kind of beat on the car for it to be apparent & maybe break a law or two in the process. Car runs like a champ otherwise & has never given me any problems at all.
This just kind of pisses me off & I'd spend a few bucks gladly if I knew how to go about it? So reading a couple responses maybe getting the car on a lift and checking bolts & driveshaft flanges might be a good start? I often wondered if it was due in part from the motor twisting on the mounts under heavy throttle that affected the pinion angle momentarily?


One thing I don't like about this car is how I feel every pebble through the steering wheel with these low profile tires. Its kind of like the princess and the pea fable LOL.

[terry_b]

Honestly, the vibration kind of comes and goes. I notice it during hard pulls on the highway one day and the next it's smooth as butter. I wonder how much of it is just normal engine and driveline vibration?

Car was recently in the shop and had the exhaust and driveshaft taken off to replace the clutch. So I know the driveshaft bolts are tight. Now I'm getting used to a different sound and feel of the twin disc clutch so it's just kind of minor for me. I don't have any issues, don't feel a loss of power, and definitely no engine codes... Paranoia?

[Stingr69]

Driveshaft bolts and nuts are one time use only. The shop may not have replaced/installed them right. No charge on your bill means they did not do it.

[qcman]

Originally Posted by terry_b

Honestly, the vibration kind of comes and goes. I notice it during hard pulls on the highway one day and the next it's smooth as butter. I wonder how much of it is just normal engine and driveline vibration?

Good point Terry I'm not sure what is normal for a rumbling V8 verses other cars. I could be chasing a non-issue so the paranoid term is spot on LOL. And in my case it has not changed at all over a few years....I would think performance mods would tend to make the car a little more harsh overall compared to stock for lack of a better term.

[TRC-SS]

any updates....been chasing this issue for a year now myself

[Moto-Mojo]

Looks like this thread died but now I have it. I put drilled and slotted rotors on a year or so ago and they're shakers themselves. I was wondering if Stabilitrac is working the brakes ever so slightly under hard pulls and transmitting my (and others) brake vibration?

[1JEWLDSSRS]

Originally Posted by Moto-Mojo

Looks like this thread died but now I have it. I put drilled and slotted rotors on a year or so ago and they're shakers themselves. I was wondering if Stabilitrac is working the brakes ever so slightly under hard pulls and transmitting my (and others) brake vibration?

Have you tried to do a pull with the nannies all turned off? To check that it isn't them. Possibility you might have a lightly warped rotor on the front. One of my friends had a C1 Concepts drilled and slotted rotor bad right from the get go. They replaced them for him and all was good.

[Moto-Mojo]

Originally Posted by 1JEWLDSSRS

Have you tried to do a pull with the nannies all turned off? To check that it isn't them. Possibility you might have a lightly warped rotor on the front. One of my friends had a C1 Concepts drilled and slotted rotor bad right from the get go. They replaced them for him and all was good.

I actually did think of that and did a few pulls. At first I thought I had a Eureka moment but then wasn't completely convinced I wasn't still feeling it. I'm also beginning to think that all the 'systems' just don't dampen the torsional vibrations that come from the motor/trans/driveshaft, etc. anymore.

When it's all new, all that rubber in the motor mounts, cradle, center bearing, driveline guibo's and on and on, is soft and pliable. And absorbs vibration. It might be a combination of all those things as dampening components begin to harden.

I remember an old, long gone friend had a '69 Chevelle 396 and that hog shuddered hard every time he got on it. Until he hit that tree! (that wasn't what got him tho!) And it was about 1977-78 when he bought this car.

[Moto-Mojo]

Now, today, I swear with the Nannie's off, the vibration is almost undetectable. Go figger!

Edit Again: it was a nice warm here day here in the Republik, so I did a bunch more hard pulls. I also decided to see how the brakes felt with the nannies off. I swear, even they felt better. (less vibration) It's almost as, if you've altered things like brakes, tunes, etc. from the OE, and software that controls the nannies is forced to deal with them, you might pick up something like rogue vibrations. Dunno.

Some of y'all try it and gimme a full report!

[1JEWLDSSRS]

Originally Posted by Moto-Mojo

Now, today, I swear with the Nannie's off, the vibration is almost undetectable. Go figger!

Edit Again: it was a nice warm here day here in the Republik, so I did a bunch more hard pulls. I also decided to see how the brakes felt with the nannies off. I swear, even they felt better. (less vibration) It's almost as, if you've altered things like brakes, tunes, etc. from the OE, and software that controls the nannies is forced to deal with them, you might pick up something like rogue vibrations. Dunno.

Some of y'all try it and gimme a full report!

Well that's pretty interesting. I have always driven my Camaro with the nannies turned off. The way I see it is that with them on, the computer is always"monitoring" the wheel speed, slippage, grip and is constantly compensating for everything detected, and adjusting brake pad pressure as needed. Next time I'm out for a therapy session, I'll leave the nannies on to see how she reacts. And remember, with these cars you are always going to have some vibration because they are just build that way. Do like I did and put solid cradle mounts in, and a 1 pc aluminum DS along with a big lumpy cam, vibration city. Feels like a race car now!!