I have an 04 GT and I've noticed that ever once and a while while accellerating in third gear around 1750-2200 RPM the car bumps slightly. I say bumps because that's the only way that I can describe it. I don't think that it happens in any other gear but that's not to say I haven't noticed it. I'm not sure if it's something to do with the engire or possibly transmission. This is my second engine in this car as the first one was a factory defect. I'm thinking that the tech that put the new engine in messed something up with the aligning of the clutch/tranny/engine. Ford says that there is nothing they can do at this point because I cannot "recreate the bumping on demand" as they put it. I guess they use the mentality that it has to break before they fix it. Any ideas?