I just bought a 2008 G8 with 46,000 miles and it has a vibration through the seat and body that I blame on lugging of the engine. It only happens when the engine rpm is under 1500. I think GM has the trans shifting too soon. Is there a higher gear ratio available for these cars as this may be the fix. I know GXP models come with 3.70 gears but I wouldn't want gears that high.
I have the vibration as well. It is only noticeable at a very light throttle position, just a little accelleration at it clears right up. Can the DoD be turned off just to see if the vibration goes away? I suspect that is the problem,but Im sure a dealer isn't going to admit it because there is no way to fix it and still keep decent mpg.
Another update! On my last thread I posted that the car was 99% fixed, which was just me getting excited I guess..... it was smooth for a few days, but everything is back shaking and vibrating and has been for months. I brought it to several places, some GM dealers, some private places and nobody has fixed it. The main issue is the lack of service I am getting from my primary dealer, but the car is back with them today and a GM specialist Engineer is working on it. Could it be the Front sway bar bushings? Rims bent? Rotors warped? Lower A-arm has too much play? Just needs an alignment? I don't enjoy the day to day anymore in my G8 as it always shakes, and I can't sell it as the shake is obvious. Just wanted to update and see if anyone has had any luck over the last year getting the vibration issue resolved and what it might have been? They've already replaced a ball joint under warranty which seems to be a problem on almost all G8's, so the clunk went away but still vibrates... HELP!!! Anyone have news or advice? I really want to keep the car. (see previous posts on this thread for the history)
Thanks, all!
Ryad
I don't have one off to measure. Do you have one that is suitable for the lower? I have an older moog chassis catalog with a dimensional reference. Measure what you have and I'll get back to you with an application.
Looking through this thread, there seems to be a couple of different problems--the first by bad tires/suspension/balancing/alignment and the other when the engine is lugging along at very low RPM. I have the second problem. I love this car except for this vibration when the engine is poking along at 1200 rpm in 6th gear. Tapping the tranny down to 5th makes the issue go away, but if I had wanted a manual transmission, I'd have bought a different car. Why oh why can't GM fix this?
I just purchased a used 2009 G8 GT and have noticed the vibration referred to in this thread. My situation is that it occurs at relatively low rpm and maintaining the same speed. When I accelerate even slightly it goes away. Most noticeable at 30 mph but notice it northward of 60 as well. The vibration/sound is like a manual when you are in a gear higher than you need but a bit more subtle.
Is there a solution or has anyone found something workable? Since the car still has the balance of some of the factory warranty I want to try and get it resolved before that runs out. Thanks!!
My G8 GT does the exact same thing most noticable at 35-40mpb. I have not brought it to a dealer yet; I hope that I am not damaging the transmittion when driving at this low 35-40mph constant speed.
Just bought one this week. I have the same vibration. It is the Displacement on Demand. I believe there is need for concern if you start consuming oil. Otherwise it is normal on this system.
PPARNAIL
I have recently bought a G8GT and am having the vibration issue discussed here. New tires, wheels in perfect balance but a " phase" vibration at 55 to 70. Sometimes steering wheel wobbles, then goes away but the droning, phase vibration always exists. I see that these previous posts are quite awhile ago. has anybody got a definitive cure for this?
I have reflashed the program with Supertuner 93 octane and disabled the AFM. That got rid of the vibration from that, but the drone( rumble) still persists.
i have a 2009 g8 which i bought with 45000 miles from a dealer. the factory tires were still on the car , with the rear ones worn alot more than the front. i wonder why ? lol. any way, even messing around with rotation, i still had a sterring wheel shake , or i should say a back and forth occelation. i drove it this way for 15000 miles. then i replaced all tires with sumotomo htzlll. plus i replaced the front rotors and pads with centric brand from my local auto part store. there is no vibration or occelation any more. one thing i did notice was alot of those tape on weights on all rims , which were balanced off the car by the tire dealer. so, i can"t say which it was . a bad rotor or tire.i did have bmr front and rear sway bars , sub frame connectors and strut brace. nothing to do with vibrations , but the car rode real rough , especially on pocked marked roads here in northern n.j. i removed every thing and went back to stock , after driving for 20000 miles. now the car rides as good as i remember when i first bought it. more compliant on uneven roads. any one instrested in bmr parts cheap , let me know.
HI, Based on information I got from one of the blog post, I loosened the bracket holding the driveshaft to the floor pan, and as I did, it moved over slightly. Retightened the bolts and took it on the highway to experience the elimination of the "phase" vibration that was plaguing the car. I still have a slight steering wheel shimmy at about 55 to solve but the annoying vibration at 65 is gone.
The AutoGuide.com network consists of the largest network of enthusiast-owned enthusiast-operated automotive communities.
AutoGuide.com provides the latest car reviews, auto show coverage, new car prices, and automotive news. The AutoGuide network operates more than 100 automotive forums where our users consult peers for shopping information and advice, and share opinions as a community.
Linear Mode
