Business ProfileforDrive Shaft Shop

I bought a drive shaft for my 07 srt8 superbee so I can run a hellcat rear-end. I received the hellcat rear-end and the drive shaft installed both and I had a horrific vibration at 80mph so I called drive shaft shop and explained my situation and the gave me some measurements and troubleshooting steps to try none of them worked so I called them back and they said that they balance their drive shafts at high speeds so he doubts that it's the driveshaft so I changed out the entire rear-end and issue still occurred so I called back the drive shaft shop and they told me to fill out rma information to ship the driveline back to test out the gentleman explained I had to pay for shipping and it can take up to 4 weeks well this is my daily driver I don't have another vehicle. He said sorry there was nothing he can do so I filled out a rma never got a response waited 2 weeks and still no reply so I filled out another rma and in the mean time I have been driving the vehicle and the vibration is getting much better so I got underneath the vehicle and all the grease has flung out of the driveline all over everything in my rear-end. So I am assuming they put to much grease in it and the grease went to one side causing a vibration because the more grease that comes out of it the faster I can go and have less vibration. So I called back a month later after last rma was sent in I still have not got a response. When I called in I asked for a supervisor I left the supervisor 2 different voice-mails asking very politely to please give me a call and no one ever called me back so called in today and they said they will look for my rma and get back to me its been almost 4 months since I first called them and they literally want nothing to do with me or to help me! Please be careful dealing with this company. I am going to post my experience on all my car groups to warn people of this company. I don't want anyone else to have this experience.