96Roadmaster

Hello, everyone. I was wondering if anyone might have any ideas on a problem with my 1996 Roadmaster wagon. The motor was absolutely perfectly tuned, with much other work having been done prior including the optispark, fuel pump and filter, etc. Nothing was left to do on the car other than the transmission which was going and then went into limp mode. I brought the car to a shop to have it rebuilt, and they gave me the runaround from the time I okay'ed the work and I was sorry I'd brought it, however it things got even worse. They gave me back the car telling me it was all set and perfect, and told me they had two or three people test drive it on the highway. Immediately when I started it up I noticed a vibration in park and neutral. One of them denied any vibration at all; another mechanic blamed it on whoever did my last tune up. Like I said, it was perfect before arriving at this shop. I proceeded home to find out once on the highway that it would not go beyond second gear. This was already at highway speed, so not good for the car, plus their guys that drove it that way on the highway, so I was very worried about the motor, especially with the new vibration. I called and they said it's fine but agreed for me to bring it back. One of them got in the car with me, had me go on the highway again and said it seems fine to him. Next one of their mechanics test drove it, said that yes it doesn't go past second, brought it in and said it was a blown valve or seal and gave it back to me again. I drove it and it was bad, making noise when reaching highway speed, with a low undertone, called them again, told them it's a mess and is nothing like it was when I dropped it off, and just kept bringing it back but getting a runaround and line of bullsheet. Now it is so bad at highway speeds that I can't tell what's going on. I have to really push the gas pedal, but it is not sputtering or acting like it's not getting enough fuel. It's simply running terribly and doesn't have very much power - maybe a quarter to half what it had before, doesn't coast but does continue to run, and is still vibrating in park and neutral. I've heard sort of a light knock a once or twice in the trial highway home but that was after they fixed the missing gears. I was wondering if anyone knows if these are signs that a pushrod was bent during the time they had only first and second gears going but drove it on the highway and sent me off with it, or if it sounds like it's something less threatening. Thank you in advance for any input anyone has.

96Roadmaster

P.S. There are no codes when scanned at the local auto store.