A few odd things going on........

Hi Bill Your window problem will likely simply be that the glass has jumped the track inside the door... If your comfortable dissassembeling the door then it could be a simple fix... that being said it should take a shop less than half a hour shop time and no shop supplies unless actual damage has been done to the mechanisim. as for the second problem i would have a shop look at it if you can... on a simple tire rotation i would instinctivley say the swapped tires could be bad but that sounds like you have another issue... could be damage from a bad jack lift point? Your coolant issue seems to be a simple quirk of these cars... If your coolant level is visibly normal then there is likely no issue... if it is leaking then places to check are at all connecting points to the engine and check the lower intake manafold... I have seen pressure issues cause blips in the electrical before and it is sometimes due to a failing water pump... The pump occasionally doesnt start when needed and gives bad reasons but starts after a few seconds... i would get it checked just to be safe...

Question 1. GM went to plastic regulator gears, chances are, that the gear stripped and the noise you hear is the motor running (since it's gear is metal!). Questions 2. Could be any of those issues you listed, although the grandams were known for their wheel bearing issues. Tie-rod end will usually cause massive wheel vibrations in a Front-wheel drive car. Sway bare link, possible. Ball joint, also possible. Question 3. GM had issues with the intake gaskets on all v6 and v8 engines produced from 2000-2005. It was caused be an improper gasket compound used by their supplier. Chances are, your intake gasket is leaking down the back of the engine, and since it is a small leak, all evaporates!!! Changing you intake gasket will correct this issue.

Thanks for the insight! Your response to my front end issue made me stop and think about all that is going on, and I also have a rhythmic "thud" that increases with the overall vehicle speed, and it's perfectly in time with a jolt of the steering wheel, similar to when you have "hot spots" on the brake rotors. Since this is happening while driving, I know it's not the brake system (plus I just replaced pads, rotors, and calipers). Going back a few years, I had a newer Cavalier before my Grand Am, had a similar issue. If my memory serves me correctly, that turned out to be the inner tie rods, and the solution was to replace the rack and pinion. I'm hoping this isn't the same!

Well a bad tie-rod end (whether it is inner or outer) makes your car feel like the lug nuts are loose on the wheels. If it is the rack, that sucks!!! Extremely difficult to get to in most cars!! To me it sounds more like a wheel bearing. My brothers Grand Am developed the same issue shortly after putting 18's on it!!

GM did not have bad intake gaskets on V8's that causes coolant leaks - there is no coolant that runs through the intake any longer on GM v8's (except the northstar and it's variants) so please stop putting the V8's in with that - the V6's did - that's a fact. The plastic gear is never the problem - I've dealt with them lots. it's a Grand Am so on this vehicle it will be the plastic sash that attaches to the bottom of the window glass with epoxy. these often break or sperate from the window glass. It's a small yellowish plastic piece about 2 inches long and has a hole for the both to attach to the regulator. this is available from your Local GM dealer and they will also have the proper epoxy instock as well. The hard part is removing what is left of the 'sash' on glass. I've won't kid you and say i've never broken the glass, but I have - it can be very difficult sometimes.