Buying a 2005 GXP tomorrow... how scared should I be?

Discuss your Bonneville GXP and/or any other Northstar powered Olds or Cadillac... Including the Intrigue / Aurora 3.5L Twin Cam V6 (Short Star ) , 4.0L and 4.6L Northstar V8's. Please use General Chat for non-mechanical issues, and Performance and Brainstorming for improvements.
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CMNTMXR57
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Re: Buying a 2005 GXP tomorrow... how scared should I be?

Post by CMNTMXR57 »

Mine was a 2004, no issues at ~90k when I sold it.

And while it's packed in there, most just unbolt the sub-frame and lift the car off it to do something like this.

Again, as posted here (or maybe it was one of the other 10 "should I buy a GXP..." threads)

You get the tougher to work on N*, but you get a pretty stout transmission behind. Wheras by comparison, say a Grand Prix GXP or Impala SS with the simpler LS4, you get still a difficult engine to work on IN the car, with a weak trans (the same 4T65E that's in your SSEi), behind a torquey, high revving V8.

It's sorta a "pick your poison" situation.
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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

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Re: Buying a 2005 GXP tomorrow... how scared should I be?

Post by ddalder »

I don't do a huge amount of mechanical work, I'm more an electrical/electronics guy. Having said that, I did replace the right (rear) cam cover and the crossover gaskets myself with virtually no difficulty. It was a little time consuming, but there was nothing hard about it. Part of the time is me just being super anal about stuff. I cleaned a bunch of components and engine bay areas during reassembly because, well, I could. Replacing head gaskets isn't something I'd tackle. As mentioned, it's far better (and not that difficult in a shop environment) to separate the engine from the car.
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CMNTMXR57
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Re: Buying a 2005 GXP tomorrow... how scared should I be?

Post by CMNTMXR57 »

I think the back is the easier of the two, factoring out the stupid main harness which has zero slack in it to facilitate room to move the cam cover out.
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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
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Re: Buying a 2005 GXP tomorrow... how scared should I be?

Post by ddalder »

Did you mean to say the back is harder? I just had a look through my photos and that's the one where the harness looks like it would be problematic. I just disconnected one harness connector and ground ring terminal bolted to the block and was able to get enough play that I had no problem. I don't see anything much in the way of the front cover. The challenge with it seems to be primarily limited to removal and correct installation of the water pump pulley.
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Turn Signal Mirrors, Center Console Courtesy Lamp, Rear Outboard Heated Seats, PVD Chrome 18" Factory Rims, Upgraded
Carbon Fibre Appearance Interior Trim, Highly Modified Main Body Harness, Instrument Panel, Door, Door Panel & Headliner
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CMNTMXR57
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Re: Buying a 2005 GXP tomorrow... how scared should I be?

Post by CMNTMXR57 »

Back is easier. Front you have to pull the water pump pulley, seal, and believe it or not, is a tighter space when lifting the cover off due to the radiator core support.

I mean neither is overly simple. It's not like my LS1 where I can have the covers off and checking pushrods, and put back together in 15 minutes tops.
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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
ddalder
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Re: Buying a 2005 GXP tomorrow... how scared should I be?

Post by ddalder »

Okay. I could see that.
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Turn Signal Mirrors, Center Console Courtesy Lamp, Rear Outboard Heated Seats, PVD Chrome 18" Factory Rims, Upgraded
Carbon Fibre Appearance Interior Trim, Highly Modified Main Body Harness, Instrument Panel, Door, Door Panel & Headliner
Wiring Harnesses, Custom Fuse Box & Tire and Loading Information Decals, Additional Acoustic Insulation[/size][/color]
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Re: Buying a 2005 GXP tomorrow... how scared should I be?

Post by jradke61 »

MikeKerr wrote:The head gaskets appear to go both with mileage and with age, it is a question of when, not if. There are no proactive actions to prevent the head gasket issue. If you buy a GXP, have 4k in the bank and hope that is enough to perform the repair, and hope you have a qualified person in your area to perform the work.

There is a reason 2005 GXPs are now often selling for less than 2005 SLEs. The GXP is a very, very expensive and high risk to maintain automobile.
Oh please. Don't go passing off 4th hand misinformation as known fact.
I'd be *dang* if you ever got your hands on my GXP cheap because of such nonsense.
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Re: Buying a 2005 GXP tomorrow... how scared should I be?

Post by BBamm »

jradke61 wrote:
MikeKerr wrote:The head gaskets appear to go both with mileage and with age, it is a question of when, not if. There are no proactive actions to prevent the head gasket issue. If you buy a GXP, have 4k in the bank and hope that is enough to perform the repair, and hope you have a qualified person in your area to perform the work.

There is a reason 2005 GXPs are now often selling for less than 2005 SLEs. The GXP is a very, very expensive and high risk to maintain automobile.
Oh please. Don't go passing off 4th hand misinformation as known fact.
I'd be *dang* if you ever got your hands on my GXP cheap because of such nonsense.
140k and NO Head gasket issues here :beerchug: You're going to love that GXP! Find the stock 18s for it and have fun. The worst thing about my car is the 2 times I've replaced the oil cooler line and it still drips... other than that, it's solid.
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ddalder
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Re: Buying a 2005 GXP tomorrow... how scared should I be?

Post by ddalder »

Yes, oil and transmission cooler lines are both bad on these. I'm on my fourth set of each. After warranty ran out, I had a set of each custom modified by a specialty shop that builds hydraulic lines. Haven't seen another leak since.
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Bose Luxury Sound System w/Touch Screen Navigation, Addition of Factory XM, 2005 MY Antenna, OnStar Upgrade (3G),
RainSense Wipers, Backup Camera, '00 Style Door Panel Courtesy Lights, Heated Washer Solvent, 2X Remote Trunk Release,
Turn Signal Mirrors, Center Console Courtesy Lamp, Rear Outboard Heated Seats, PVD Chrome 18" Factory Rims, Upgraded
Carbon Fibre Appearance Interior Trim, Highly Modified Main Body Harness, Instrument Panel, Door, Door Panel & Headliner
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Re: Buying a 2005 GXP tomorrow... how scared should I be?

Post by NashvilleGXP243 »

Mine has 168k on it. No head gasket problems whatsoever.
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Re: Buying a 2005 GXP tomorrow... how scared should I be?

Post by jradke61 »

BBamm wrote:
jradke61 wrote:
MikeKerr wrote:The head gaskets appear to go both with mileage and with age, it is a question of when, not if. There are no proactive actions to prevent the head gasket issue. If you buy a GXP, have 4k in the bank and hope that is enough to perform the repair, and hope you have a qualified person in your area to perform the work.

There is a reason 2005 GXPs are now often selling for less than 2005 SLEs. The GXP is a very, very expensive and high risk to maintain automobile.
Oh please. Don't go passing off 4th hand misinformation as known fact.
I'd be *dang* if you ever got your hands on my GXP cheap because of such nonsense.
140k and NO Head gasket issues here :beerchug: You're going to love that GXP! Find the stock 18s for it and have fun. The worst thing about my car is the 2 times I've replaced the oil cooler line and it still drips... other than that, it's solid.
I've got the stock 18s. They've got BFG G-Force Sport Comp 2 tires on them that would be totally useless in the snow. These came with the car as well and have all season Firestone tires on them for winter.
Replaced the fog lights and repaired the ground wire on one of them. Left the splash guards off after replacing the bulbs. No issues since.
Other than that, no troubles. I did normal maintenance stuff including Plugs/Coil Packs when I bought it like I do any car/truck/bike I buy just for piece of mind no matter what the seller claims.
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