My 2005 GXP has finally come to the point where it just can't be driven without putting at least a gallon of coolant in for a 20 minute drive, as well as a liter of oil every tank full of gas.
The car has 285,000 Km on it, I really do like it and it's in great shape other than the infamous blisteriing under the fuel door, this is my 4th Bonneville and they all did that.
It defies all logic as to why they would put foam in the cavity under there.
So it's getting a "new" engine, 160,000 Km on it, less than the car had on it when I got it.
I paid $4500 Cdn. back in 2012, putting 2 to 3 thousand into it is a reasonable enough expense to warrant keeping it, I haven't seen anything out there that would come close to replacing it for that kind of money.
Surprisingly the engine is cheap enough at $400 Cdn., the labour is about 20 hours to swap it out, if I were 20 years younger and 40 years dumber I would be inclined to do it myself but my body and mind just don't need the abuse.
I know there will likely be some scolding for not doing the head studs, but if I get another 100,000 Km out of it I am reckoning that by then the rest of it will be past it's useful life.
I borrowed a 2006 CTS in the mean time, not that they are all that bad, but I'll sure be glad to get back in my GXP, it's hard to explain to some but it just has character, not like the soulless CTS!
All in all it's a love/hate relationship, we all know the feeling!

I'd have gotten rid of it personally. 285k kilometers is around 177k miles in our speak. Definitely "long in the tooth" and a ~12 year old car.

Personally, that CTS has way more character, a much more competent chassis, driven by the right set of wheels vs. a wrong wheel driven, nose heavy, size 10 engine stuffed in a size 5 dress, package. Bonneville's are great cruisers and solid platforms, but aren't really in the same league in terms of chassis dynamics.

_________________


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
2007 Chrysler Town & Country Limited: Sold to neighbor
2009 Pontiac G8 GT: L76, Sport Red Metallic
2003 Chevrolet Suburban 2500: Doeskin Tan - 8.1L Big Block... new plow truck
1999 Chevrolet Suburban: Sunset Gold Metallic - Daddy's winter beater and plow truck

Yes, it's 12 years old, almost 13 actually and I guess I am compelled to show sympathy for orphans!
I figure that the total investment including purchase price keeps it at about $1000 per year to drive a something better than a basic grocery getter that's not like every other car on the road.
Surprisingly the GXP and the CTS get pretty much identical fuel mileage under the same driving circumstances, I wouldn't have guessed that.
I've always liked the looks of the CTS, more so the newer body, yes they are quite a competent performing car, unfortunately there's something with them that just doesn't click for me or I'd own one.
Must be somewhat common, considering the selling price of used ones, they seem to sell for about the same as a Mazda 3.
I have to say that right wheel driven verses wrong wheel driven depends on the expectation one has for their vehicle based on how and where they do the bulk of their driving.
With our winter conditions a FWD car will almost always get the job done more effectively than a RWD car, particularly without winter tires.
I'm chuckling about the size 10 engine in a size 5 dress analogy, the 1960's and early '70's blew that right out of the water, that was more like a size 14 engine in a size 0 dress!
At least they didn't get confused about which end the driving wheels should be on though, except for GM with the Toronado and Eldorado!
In case it sounds like I'm pro FWD, I do have a RWD car/toy as well, but it's really old, about 35 years, has an DOHC 4.6 liter aluminum V8, in the front, three pedals, neither of which are an E brake.
Oddly enough it has a horsepower rating that's about the same as what some new minivans have, there must be some difference with the size of horses they use!

If I were you I would really consider studding that used engine before it is installed. Fairly easy to do especially when its already out of the car! Come on... you can do it!

http://www.northstarperformance.com/sgstuds.php

I get the usage thing, I get the weather thing, I do live in Chicago. It may not be Canaidia, but still.

Part of the reason you see them so cheap for sale, is because of the issue that 300 brings up, studding the engine before putting it in. These things do have a rep, unfairly so, but still have one.

And yes, on paper, my Wife's mini-van is step in step with this engine.

_________________


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
2007 Chrysler Town & Country Limited: Sold to neighbor
2009 Pontiac G8 GT: L76, Sport Red Metallic
2003 Chevrolet Suburban 2500: Doeskin Tan - 8.1L Big Block... new plow truck
1999 Chevrolet Suburban: Sunset Gold Metallic - Daddy's winter beater and plow truck

I definitely mulled doing the studs while the engine was still out on the floor, the way I see it It's a double edged sword, another $600+ for the studs, plus gaskets, a day of my time and for sure a more reliable outcome verses taking a leap of faith that it will last another 100,000 Km before it goes again which at that point I may be able to make up my mind as to what I'll get next.
I did find a N* with about 80,000 Km on it, not close enough to me to make sense, if I were going with it I would definitely have restudded it.
Actually the Canajun manufacturer of the studs started about 40 miles away from me.
It seems that this was yet another example of the engineering prowess that some auto makers can't get away from, why would you put ANY fine thread fasteners into aluminum!
All in all I'm going to hope for the best

I spent Sunday sorting out why the windows stopped working on the CTS, pretty simple, splices in 16 ga wire to connect the power for the window motors really shouldn't be on the rear passenger side floor, especially when they are laying in a 1/4 inch of water and the foam underlay is soaked.
It's asinine to think that there will never be any water or moisture there, if it is absolutely unavoidable then you would think that they would at least insulate them with something better than electrical tape!
They were that neat green colour and fuzzy, the drain holes in the door had plugged and the door had about a foot of water in it, I presume that some of the water drained over the rocker into the footwell.
Apparently having this splice corrode is not uncommon, gotta wonder!
Even the battery is "special", and pricey and considering that batteries don't flourish in a somewhat hot location being at the firewall can't be helping matters.

I was referring to the resale price of the CTS's, seems that they can be had for a very affordable price, hell of a car for $4000, as long as it has no issues and you are mechanically inclined, particularly considering the new price for one.

I have always pondered whether Korean horses, North American horses and German horses are all the same size!

When it comes to cars, bikes, boats and the rest of the "toys" we love, logic is rarely a prevalent consideration for the reasons we do what we do, it's who we are!

GM does the same with a wiring harness on the Bonneville. A lot of people have non-functioning windows on one side, locks that don't work etc, and it's usually found in the wiring junction under the carpet that has corroded out, especially those with sunroofs, which is another issue on these cars.

As to fine threads on aluminum, I think a lot has to do with the fact that the N*, along with GM's "X" motor, was one of the first all aluminum, in house designed and manufacturer engines they did. It first came out in 1991, which means it was on the drawing board in the mid-80's. So this was all new territory to them. Up until then, everything they did was small block V8's or 60* 3.8/3.1/3.4L V6's, 90* 3.8L & 4.3L V6's with cast iron blocks. The engine in that timeframe that was all aluminum was the LT5 used in the Corvette ZR1 but that was designed by Lotus with help from GM and assembled by Mercury Marine.

By the time the GenIII V8's came out, GM had learned a lot of lessens about aluminum engine construction, although there were still some issues (like block casting/porosity issues with LS1's).

I personally don't think 1st gen CTS's have weathered time too well personally. All the ones I see around here, with the exception of a few, are beat hard and look it.

_________________


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
2007 Chrysler Town & Country Limited: Sold to neighbor
2009 Pontiac G8 GT: L76, Sport Red Metallic
2003 Chevrolet Suburban 2500: Doeskin Tan - 8.1L Big Block... new plow truck
1999 Chevrolet Suburban: Sunset Gold Metallic - Daddy's winter beater and plow truck

I'm not at all a fan of sunroofs, never will be, as far as I know they all leak, at least they designed drains into them, and they never plug up either!

1969 ZL1 427, all aluminum, no excuses, they got that one right!

There are 1st gen CTS's that have hung in reasonably well, as long as they have had some sort of corrosion inhibitor applied regularly and the owner had some appreciation for their investment!
The old adage, oil is cheaper than an engine and all the under body components that corrode away if they don't get some!

I seem to recall, those engines were purpose built, only available through the COPO network, with non-standard GM Hi-Po Parts. I want to say that the block wasn't done in a GM foundry either.

_________________


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
2007 Chrysler Town & Country Limited: Sold to neighbor
2009 Pontiac G8 GT: L76, Sport Red Metallic
2003 Chevrolet Suburban 2500: Doeskin Tan - 8.1L Big Block... new plow truck
1999 Chevrolet Suburban: Sunset Gold Metallic - Daddy's winter beater and plow truck

Perhaps you can have your cake and eat it too.

Honestly refurbishing a Northstar goes beyond just the head studs. There's the half case gasket to consider as well ; by the time you tear down the motor to fix that you may as well strip it down to the crankshaft and start totally fresh. As in upgraded crankshaft, forged rods and pistols, high performance cams from the 300 HP Northstar motor plus port and polish on the heads.

Right now it's just a matter of keeping a good car on the road, but sooner or later your replacement motor will do the same thing. When it does , that's when you go full Monte on a rebuild as described above- which point you just bolt a 100 shot wet kit Nitrous setup to it and Shazam! It won't be cheap, but you'll have two things; a bulletproof car ,and guaranteed votes for Car of the Month.