What is this vibration? Advice appreciated

[CALLAWAY11]

Hey there, my car started vibrating and it seems to be getting worse. I dont drive the car that much because its been in the shop getting random things done but i noticed it about 100 miles ago on a high speed run in Mexico I’m now feeling it doing 50. When driving the car it only happens when you are accelerating. As soon as you push a little bit of gas over 50 mph you can feel it and it increases as you go faster. But when you let go of the throttle, it stops. So its only on load. My shop thought it was my driveshaft and I replaced it with a one piece aluminum from DSS and it still does it. I have Gforce upgraded axles and on the drivers side axle, a little bit of grease is coming out. Its not a ton but its coming out. Could it be that axle? I’m not sure. But the axle is spinning the whole time, so it should do it, i think, regardless of the car accelerating or decelerating. I still have my old OEM axles and might try that. They are going to do a high speed balance on my wheels just to rule that out. But I dont think its my transmission or my rear end but im not sure. Does anyone have any ideas what they think is happening?

[steakmaker]

Have the engine mounts checked out.

[Moto-Mojo]

Where do you feel this vibration? And what frequency is it, as in, the steering wheel of seat of the pants? More engine or tire/wheel rpm?

[LHRxDeadx]

bro ive been chasing one for a year now man still no luck. im well over 5k in parts that ive changed thinking that was it. ( i needed the parts any ways for my power level)
if you find anything out let me know

[jergarr]

Yeah ive got a similar vibration except i feel it over 25 mph. I only feel it on acceleration as well. I checked the driveshaft and there were no loose or broken bolts. The axles look good as well. Im starting to think it could be the exhaust.

[BandRcAMARO]

I had a similar issue, honestly just kept driving it and it went away in around 1k miles or so by itself

[mickss]

Good luck with trying to isolate a vibration, there`s so many rotating and moving parts of a car that you`ll probably go broke replacing suspected parts or insane before you find the problem.

[farm rat]

Kind of a stupid idea maybe, but could you maybe have a loose exhaust piece?

[PalmerGA]

Originally Posted by farm rat

Kind of a stupid idea maybe, but could you maybe have a loose exhaust piece?

Or lug nut(s)?

[christianchevell]

the usual Idea is the slop in bad u joints...… It happens under load being more key to it. Good Luck. I don't know what you have done to stiffen the rear or what I use poly bushings LPW cover, BMR////

[UBB]

are they good vibrations and are they giving you excitations? :P

[CALLAWAY11]

Well, we found the vibration. It was my axles. We put on my old OEM axles just to eliminate an option on what it could be and that was it. I thought the vibration was happening at higher speeds but after we changed the axles the car drives so smoooth now. It blows my mind that i went thru two sets of aftermarket axles and both failed from two different companies. The good news is the Gforce axles have a life time warranty and they will get fixed. I’m going to leave the stock ones in until they break and have the Gforce as a backup. Thanks for all the help and recommendations.

[RJT Impala]

Originally Posted by CALLAWAY11

Well, we found the vibration. It was my axles. We put on my old OEM axles just to eliminate an option on what it could be and that was it. I thought the vibration was happening at higher speeds but after we changed the axles the car drives so smoooth now. It blows my mind that i went thru two sets of aftermarket axles and both failed from two different companies. The good news is the Gforce axles have a life time warranty and they will get fixed. I’m going to leave the stock ones in until they break and have the Gforce as a backup. Thanks for all the help and recommendations.

Safe to interpret this as they are going back for corrective action and/or replacement? Lifetime warranty and all....