Should I Buy an 04 Bonneville GXP?
Should I Buy an 04 Bonneville GXP?
Found a 2004 Bonneville GXP online with 33k miles for $7000. Car looks like it's in really good shape inside and out. I'm not going to buy this one specifically, but I'm in the market for a new car and I like the 01 SLE that I have right now. I really like this GXP, but from what I've read online about the northstar, it's kind of scaring me. I don't what to put a *shoot* ton of expensive repairs in to it, and assuming I find another car like this, I'd like to get at least another 100k miles out of it. 80% of the miles I would be putting on it would be highway miles, what do you guys think?
- nos4blood70
- Certified Bonneville Nut

- Posts: 9522
- Joined: Mon May 10, 2010 6:11 pm
- Year and Trim: 2003 SLE
- Location: Chicago, IL
Re: Should I Buy an 04 Bonneville GXP?
The Northstar is great until it breaks on you and empties your bank account, which it seems 90% of them are prone to doing.
As our resident former GM tech Lane likes to put it, it's a 100k mile motor in its stock untouched configuration, unless you're very lucky!
As our resident former GM tech Lane likes to put it, it's a 100k mile motor in its stock untouched configuration, unless you're very lucky!
Re: Should I Buy an 04 Bonneville GXP?
I own a 2004 Bonnneville GXP, ordered it new and drove it until Feb of this year, 148,385 miles. Did not have any major issues with the Northstar. Replaced water pump, intake gaskets and mass air flow sensor. Other than those items it was issue free until someone failed to yield the right of way and totaled it for me.
- CMNTMXR57
- Certified Bonneville Nut

- Posts: 5841
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- Year and Trim: 2006 STS-V, 2004 GTO, 2009 G8 GT
- Location: CHICAGO
Re: Should I Buy an 04 Bonneville GXP?
OMG, I understand that you're a newbie, so please don't take this the wrong way, this question gets asked roughly once a week. If you use the search function, you'll see we've answered this "Should I get a GXP" question ad nauseum.
It is a more "complicated" engine (for GM), that is a size 10, shoved in a size 5 dress.
It likes to;
- Leak oil
- Leak coolant
- Leak trans fluid
- Tempermental ignition system as they age
- Has the starter, which will fail at some point, in a weird location (under the intake manifold/plenum)
- And some have the lingering Northstar head stud issues (I.E. overheating).
Aside from that it suffers the normal maladies plaguing any Bonneville of this generation which is generally electrical/electronic gremlins (IP issues, blend motor issues, power issues in harness under carpet), sunroof drain cloggage, steering wheel clunk, front engine mount breakage, and probably a few other I'm forgetting.
It is a more "complicated" engine (for GM), that is a size 10, shoved in a size 5 dress.
It likes to;
- Leak oil
- Leak coolant
- Leak trans fluid
- Tempermental ignition system as they age
- Has the starter, which will fail at some point, in a weird location (under the intake manifold/plenum)
- And some have the lingering Northstar head stud issues (I.E. overheating).
Aside from that it suffers the normal maladies plaguing any Bonneville of this generation which is generally electrical/electronic gremlins (IP issues, blend motor issues, power issues in harness under carpet), sunroof drain cloggage, steering wheel clunk, front engine mount breakage, and probably a few other I'm forgetting.

Retired Bonneville Owner and former GM Tech:
2004 Pontiac Bonneville GXP: Black/Ebony *SOLD*
Summer Toys: Combined 827 RWHP / 877lb/ft RWTQ
2004 Pontiac GTO: Impulse Blue Metallic/Black/M6: lots 'o mods, 415 RWHP / 405lb/ft RWTQ!
2006 Cadillac STS-V: Light Platinum Metallic/Light Gray/A6 - Spectre CAI, Magnaflow exhaust, Speed Inc. tune, 412 RWHP / 472lb/ft RWTQ
Daily Drivers:
2019 Chrysler Pacifica Limited: Mommy's new RGC
2015 Chrysler Town & Country Limited Platinum: Kids new RGC
2011 Camaro SS
2009 Pontiac G8 GT: L76, Sport Red Metallic
2004 GMC Sierra 2500HD: Victory Red - 8.1L Big Block and Allison
2003 Chevrolet Suburban 2500: Doeskin Tan - 8.1L Big Block... RIP
1999 Chevrolet Suburban: Sunset Gold Metallic - RIP
- CMNTMXR57
- Certified Bonneville Nut

- Posts: 5841
- Joined: Wed May 13, 2009 10:45 pm
- Year and Trim: 2006 STS-V, 2004 GTO, 2009 G8 GT
- Location: CHICAGO
Re: Should I Buy an 04 Bonneville GXP?
Oh yea, don't forget fog lights...
There is a whole dedicated thread in the GXP section pertaining to this. I would bet, with a highly probable statistical analysis, that if you turn on the fog lights of the GXP you're looking at, at least one of them is out.
There is a whole dedicated thread in the GXP section pertaining to this. I would bet, with a highly probable statistical analysis, that if you turn on the fog lights of the GXP you're looking at, at least one of them is out.

Retired Bonneville Owner and former GM Tech:
2004 Pontiac Bonneville GXP: Black/Ebony *SOLD*
Summer Toys: Combined 827 RWHP / 877lb/ft RWTQ
2004 Pontiac GTO: Impulse Blue Metallic/Black/M6: lots 'o mods, 415 RWHP / 405lb/ft RWTQ!
2006 Cadillac STS-V: Light Platinum Metallic/Light Gray/A6 - Spectre CAI, Magnaflow exhaust, Speed Inc. tune, 412 RWHP / 472lb/ft RWTQ
Daily Drivers:
2019 Chrysler Pacifica Limited: Mommy's new RGC
2015 Chrysler Town & Country Limited Platinum: Kids new RGC
2011 Camaro SS
2009 Pontiac G8 GT: L76, Sport Red Metallic
2004 GMC Sierra 2500HD: Victory Red - 8.1L Big Block and Allison
2003 Chevrolet Suburban 2500: Doeskin Tan - 8.1L Big Block... RIP
1999 Chevrolet Suburban: Sunset Gold Metallic - RIP
- nos4blood70
- Certified Bonneville Nut

- Posts: 9522
- Joined: Mon May 10, 2010 6:11 pm
- Year and Trim: 2003 SLE
- Location: Chicago, IL
Re: Should I Buy an 04 Bonneville GXP?
Or both! lol
- kc9dre
- SLE Member

- Posts: 40
- Joined: Wed Oct 18, 2017 9:26 pm
- Year and Trim: '03 SLE Silver/Charcoal
- Location: Martinsburg, IN
- Contact:
Re: Should I Buy an 04 Bonneville GXP?
ok so I just updated my list to SLE's and SSEi's... I forgot about the northstar issues.
2002 SLE "Frankenbonnie" 02 engine, 04 transmission, and a 03 PCM to make everything talk. Sadly I know longer own
1993 Suburban Zombie Apocalypse Assault Vehicle (GMC Edition)
2003 Yukon Black/Charcoal cloth 4x4 POW/MIA
2003 SLE Silver/Charcoal (New Acquisition)
1993 Suburban Zombie Apocalypse Assault Vehicle (GMC Edition)
2003 Yukon Black/Charcoal cloth 4x4 POW/MIA
2003 SLE Silver/Charcoal (New Acquisition)



