Engine/transmission

I have a 97 GTP that i bought at 60K.It has 120K miles on it now.
I am going to for some maintainence on it.I have a few questions.
1. I have never changed the transmission oil since i bought it.What kind of oil should i put in it now(Just getting oil and filter change)?
2. In park, I feel some vibration coming to the me on the driver seat? Are the motor mounts getting bad?
3. The supercharger tensioner pulley is making some noise.Should i get it changed?Is it true that the assembly has heater hoses in it too and cost around atleast 70 bucks?Is there any other way to fix the sound(may be change bearings or so)?

Any kind of help will be appreciated

to answer your questions:
1. Do not let anyone talk you into a fluid exchange/flush, as there is a good chance it will ruin your tranny. Use Dexron III fluid and a quality filter and all should be peachy.
2. A vibration felt in the seat can be many different things. It could even be the belt tensioner you mention in question 3. If you only feel it in park, it could be a flywheel or torque converter going.
3. Is it the supercharger belt tensioner or the main drivebelt tensioner? The main belt tensioner has the cooling tubes running thru it, the super charger one does not.

Thanks Rick for the quick reply.
I feel slight vibration while driving on the highway.I was thinking that the tires may be out of balance.
The tensioner is for the supercharger.

I have A 1998 GP with 125k on it .THe problem is when i get into the car and put it in gear it want respond and i have to rev it up for a moment or so and swap from going from reverse to drive while gently revving arouound3000rpmfor a few second ,then it will slowly catch and take o n off and do well and just fine.I have changed fluid and filter twice.I scanned it with an OBD 2 and got a code ofPO742 wich states Torque Converter Circuit Stuck On. Please Help! Im desperate.

teI have A 1998 GP with 125k on it .THe problem is when i get into the car and put it in gear it want respond and i have to rev it up for a moment or so and swap from going from reverse to drive while gently revving arouound3000rpmfor a few second ,then it will slowly catch and take o n off and do well and just fine.I have changed fluid and filter twice.I scanned it with an OBD 2 and got a code ofPO742 wich states Torque Converter Circuit Stuck On. Please Help! Im despera.

sounds like your TCC is shot.

sounds like your TCC is shot.
What is needed to fix this problem as cheaply as possible.I dont want to put alot of money in it as my plans were to sell it from the time i aquired it.PLease give me some good news.Thanks,Bummed out in Fl

I replaced S/C tension pulley...97 Regal GS....I heard same noise and figured i could "Get more miles" from it. When the bearing seized , i heard the belt snap, and fell to the road beneath the car. The pully had melted, it was plastic. Problem is ...if S/C belt snaps, it could get caught in the main serp belt. And cause other damage. To replace was real easy, and pretty cheap too.

teI have A 1998 GP with 125k on it .THe problem is when i get into the car and put it in gear it want respond and i have to rev it up for a moment or so and swap from going from reverse to drive while gently revving arouound3000rpmfor a few second ,then it will slowly catch and take o n off and do well and just fine.I have changed fluid and filter twice.I scanned it with an OBD 2 and got a code ofPO742 wich states Torque Converter Circuit Stuck On. Please Help! Im despera.

i had EXACT same problem. a solenoid in the tranny went that controllins shifting i guess. had to have the thing pulled part and replaced. around 400 bux and 3 days after all was said and done...

unplug the connector for the TCC. If you don't drive the car long distances, you will see no ill effects. The TCC locks the torque converter and improves highway mileage. On a long trip, the tranny will run hotter due to the converter slipping if you unhook it.