1998 Grand Prix GTP

  1. Welcome to GM Inside News Forum – General discussion forum for GM

    Welcome to GM Inside News Forum - a website dedicated to all things GM.

    You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, at no cost, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, Join GM Inside News Forum today!
     
Page 1 of 2 12 LastLast
Results 1 to 15 of 24

Thread: 1998 Grand Prix GTP

  1. #1
    Walking
    Join Date
    May 2011
    Posts
    6
    Thanks
    0
    Thanked 0 Times in 0 Posts

    1998 Grand Prix GTP

    What can you tell me about this car? Considering buying a 1998 used. Just read something that suggests the GTP requires premium gas. Is this so? I'm on limited budget so economy is important. However, also having trouble finding decent used vehicle in my price range. My last car died on me at 350,000 miles. Desperate to get wheels and not many gas sippers out there in my price range (under $5,000).

  2. Remove Advertisements
    GM Inside News
    Advertisements
     

  3. #2
    News Contributor BlackGTP's Avatar
    Join Date
    Jul 2008
    Location
    Connecticut
    Posts
    14,012
    Thanks
    5,590
    Thanked 7,963 Times in 3,993 Posts
    My Ride
    2013 Cadillac ATS - Black

    Re: 1998 Grand Prix GTP

    I had an '02 GTP and yes, it requires premium. My understanding is that any supercharged engine requires premium as the supercharger can force so much air into the engine so quickly that it can cause a lot of premature detonation if lower octane gas is used - basicly blowing up the engine. I'm no pro - so if someone with more expertise in the area can correct me....

    Also, at one point I filled my car up in New Jersey where they pump the gas. The guy put in regular. I at first didn't realize it but noticed the car running very poorly. I pulled the receipt out of my pocket and saw it was the wrong octane....

  4. #3
    6.2 Liter LS9 Supercharged V8 MrCritical's Avatar
    Join Date
    Aug 2008
    Location
    South Of The North
    Posts
    6,363
    Thanks
    0
    Thanked 6 Times in 5 Posts

    Re: 1998 Grand Prix GTP

    Quote Originally Posted by DebitM View Post
    What can you tell me about this car? Considering buying a 1998 used. Just read something that suggests the GTP requires premium gas. Is this so? I'm on limited budget so economy is important. However, also having trouble finding decent used vehicle in my price range. My last car died on me at 350,000 miles. Desperate to get wheels and not many gas sippers out there in my price range (under $5,000).
    These are fun cars, but not for the budget minded. Superchargers are expensive, and often need replacement after time/mileage. And it does require premium.

  5. Remove Advertisements
    GM Inside News
    Advertisements
     

  6. #4
    Walking
    Join Date
    May 2011
    Posts
    6
    Thanks
    0
    Thanked 0 Times in 0 Posts

    Re: 1998 Grand Prix GTP

    Thanks for the heads up guys. I appreciate it. Any comments about the reg. 3.8L engine? Any suggestions for good older cars that are reliable and more economical?

  7. #5
    6.2 Liter LS9 Supercharged V8 MrCritical's Avatar
    Join Date
    Aug 2008
    Location
    South Of The North
    Posts
    6,363
    Thanks
    0
    Thanked 6 Times in 5 Posts

    Re: 1998 Grand Prix GTP

    Regular 3.8 is great, some with composite intake will need intake gasket if it hasn't been done. Other than that, they're good to go.

    The same year model Olds with 3.8 is also a good buy (Olds 88, ect). Stay away from the Aurora unless it has the 3.8 engine.

  8. #6
    Walking
    Join Date
    May 2011
    Posts
    6
    Thanks
    0
    Thanked 0 Times in 0 Posts

    Re: 1998 Grand Prix GTP

    Thanks. I really appreciate the input.

  9. #7
    6.2 Liter LS3 V8 Lowboy's Avatar
    Join Date
    Sep 2010
    Location
    Ohio
    Posts
    3,528
    Thanks
    189
    Thanked 474 Times in 301 Posts
    My Ride
    Cruze 2.0L Turbo Diesel

    Re: 1998 Grand Prix GTP

    There are plenty of mid '90s GM cars with the standard 3800 out there too choose from and should have no problem meeting you budget.
    Buick--LeSabre,Park Ave(not Ultra) and Regal
    Olds--88,98,Cutlass Supreme
    Pontiac--Bonneville, Grand Prix
    Chevrolet--Lumina,MonteCarlo

    Then there are the cars with the 3.1/3400(non-DOHC) which run along time as well. Need to watch lower intake gaskets on those also.

    If you find a 3800 powered car you like and it does not have any engine repair history budget for having the lower intake manifold gaskets replaced and inspect/replace the upper manifold plenum. If the plenum part# is 89017272 I do not recommend buying a GM part. The last ones I looked at, within the last 12 months, were still made the same way the originals were. Aftermarket has addressed the issue and added material too the coolant transfer tubes and included a reduced diameter heat tube for the egr gasses.

  10. #8
    News Contributor BlackGTP's Avatar
    Join Date
    Jul 2008
    Location
    Connecticut
    Posts
    14,012
    Thanks
    5,590
    Thanked 7,963 Times in 3,993 Posts
    My Ride
    2013 Cadillac ATS - Black

    Re: 1998 Grand Prix GTP

    Note: when you aren't beating on the GTP/constantly engaging the supercharger it will return similar milage to the non-supercharged 3.8. Plus premium still costs the same 30 cents a gallon more than regular. So will the extra 30 be a huge burden? My father in law always went around saying "bet you wish you didn't have to use premium" when gas first spiked after Katrina. In a 15 gallon fillup it costs $4.50 extra (30 cents) no matter what the price of gas....

  11. #9
    R2-D2 Astromech Droid Smaart Aas Saabr's Avatar
    Join Date
    Oct 2003
    Location
    Montréal, Québec
    Posts
    18,488
    Thanks
    260
    Thanked 279 Times in 218 Posts

  12. #10
    R2-D2 Astromech Droid Premium Member Neanderthal's Avatar
    Join Date
    Nov 2004
    Location
    A sunny cave in Transylvania
    Posts
    34,131
    Thanks
    8,291
    Thanked 6,698 Times in 4,156 Posts
    My Ride
    17 Soul&/01 PT LTD/15 JD130

    Re: 1998 Grand Prix GTP

    LeSabre is probably as good a bet as any for a used car. Lots of space, 3.8, auto leveling, and usually they're owned by people who take care of them.
    A couple of years back I drove one that had just turned 100,000. Normally that's way past the miles I'll look at a car.
    But an older couple had owned this, they'd had it regularly serviced at the original dealer where the widow later traded it in, it was tight physically and mechanically, had quality tires, and would have made a great car.

    I didn't buy it, I'd have to go search for the post, but I believe they were asking five or six grand for it but would have likely taken three since they probably told the widow-woman they were doing her a favor by giving her a grand for it.
    2017 Soul &, Titanium

    Where liberty dwells, there is my country. Benjamin Franklin

    The natural progress of things is for liberty to yield and government to gain ground. Thomas Jefferson

    Hidden Content Hidden Content Hidden Content

  13. #11
    R2-D2 Astromech Droid Smaart Aas Saabr's Avatar
    Join Date
    Oct 2003
    Location
    Montréal, Québec
    Posts
    18,488
    Thanks
    260
    Thanked 279 Times in 218 Posts

    Re: 1998 Grand Prix GTP

    A LeSabre is a good choice for low maintenance costs, but it is about as fun as a funeral...



    100% free webcam site! | Awesome chicks and it is absolutely free! | Watch free live sex cam - easy as 1-2-3

  14. #12
    News Contributor BlackGTP's Avatar
    Join Date
    Jul 2008
    Location
    Connecticut
    Posts
    14,012
    Thanks
    5,590
    Thanked 7,963 Times in 3,993 Posts
    My Ride
    2013 Cadillac ATS - Black

    Re: 1998 Grand Prix GTP

    Quote Originally Posted by Smaart Aas Saabr View Post
    the car runs fine on regular
    Not when I had a tank of regular. It was fine as long as I feathered the throttle and didn't engage the supercharger. When the supercharger was engaged it did not sound good at all.

  15. #13
    6.2 Liter LS3 V8 Lowboy's Avatar
    Join Date
    Sep 2010
    Location
    Ohio
    Posts
    3,528
    Thanks
    189
    Thanked 474 Times in 301 Posts
    My Ride
    Cruze 2.0L Turbo Diesel

    Re: 1998 Grand Prix GTP

    If looking for economical used transportation avoid the superchared cars IMO.
    There is extra maintenance involved and many have been driven hard, save for maybe the Buick Park Ave Ultras. I've seem many a trashed S/C Rivera.

    S/C cars have two accesory drive belts, two tensioners, double the belt idlers etc. Blower oil should be changed as a maintenance item, blower drive puck wears out. Fuel pumps have a different wiring on the GTPs also. My brother went through 3 pumps/relays on his '98 GTP by 140K and the first he had to wait for back ordered parts.

  16. #14
    R2-D2 Astromech Droid Premium Member Neanderthal's Avatar
    Join Date
    Nov 2004
    Location
    A sunny cave in Transylvania
    Posts
    34,131
    Thanks
    8,291
    Thanked 6,698 Times in 4,156 Posts
    My Ride
    17 Soul&/01 PT LTD/15 JD130

    Re: 1998 Grand Prix GTP

    Quote Originally Posted by Smaart Aas Saabr View Post
    A LeSabre is a good choice for low maintenance costs, but it is about as fun as a funeral...
    Cheaper to put anti roll bars and good tires on it than fix superchargers and blown trannies yep.
    2017 Soul &, Titanium

    Where liberty dwells, there is my country. Benjamin Franklin

    The natural progress of things is for liberty to yield and government to gain ground. Thomas Jefferson

    Hidden Content Hidden Content Hidden Content

  17. #15
    6.2 Liter LS3 V8 Lowboy's Avatar
    Join Date
    Sep 2010
    Location
    Ohio
    Posts
    3,528
    Thanks
    189
    Thanked 474 Times in 301 Posts
    My Ride
    Cruze 2.0L Turbo Diesel

    Re: 1998 Grand Prix GTP

    Quote Originally Posted by Smaart Aas Saabr View Post
    A LeSabre is a good choice for low maintenance costs, but it is about as fun as a funeral...

    From the OP:
    I'm on limited budget so economy is important.
    A LeSabre would be an excellent choice.

  18. Remove Advertisements
    GM Inside News
    Advertisements
     

Page 1 of 2 12 LastLast

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Powered by vBadvanced CMPS v4.1.2