First off LIM/UIM issues have no bearing on Northstars. Never been an issue. In older Northstars the head gaskets were an issue. One issue in early models was the PCM didnt cycle the cooling fans properly and caused teperature rise enough for head warpage for the gasket to fail. Another was the zerts pressed into the aluminum blocks failed and the headbolts actually pulled out/snapped. All pre-04 issues. To this day when the engines are ran hot in "limp home Mode" heads warp and gaskets fail. People hear of this "survival feature" and drive them when something else caused coolant loss. In normal service I have seen No evidence of newer (04 +) LD8'* having a history of headgasket issues. And they are in more cars than just the GXP. Any engine can have one, and an all aluminum one is more prone to one if overheated, but it isnt a common issue. kewpie'* post is the first I've heard of a N* headgasket blown here is this forum. From personal experience, mine runs as smooth and quiet as the day I got it with 37k on it and more bottles of nitrous than I can remember. (20+) If anyone has taxed cylinder pressures on this version of the LD8, it would be me.

Alright, so the car is now in the hands of Cadillac. They'll be getting me a diagnosis later today. I called the warranty company and everything mentioned in the first post is covered except for cooling hoses and, conveniently, the oil cooler lines.

So all power steering components, tie rods, wheel hub bearings, cv joints, engine mounts, and the steering shaft are covered.

So back to the oil cooler lines. I'm going to need to do these myself, so if anyone can help me, this would be very much appreciated.

First off, I need the part number for what I need to replace, so I can order it off rockauto.com if at all possible. Second, I need to know where they are on the car, since I haven't checked yet. Lastly, I need to know how difficult they are to replace. Is it just the fittings that are leaking, or do the lines themselves need to be replaced?

Lastly, if I can't order them off rockauto, I need to know how much they will cost me in parts. I'd rather do this myself since it seems some people have had them replaced as many as 3 times in less than 100,000 miles, so at least that way I can do it right, or find the source of the recreating problem to design some kind of remedy.

Alright, I got pricing on the oil cooler lines. They're dealer-only items and need to be ordered, and they're $45.83 each + tax, which includes fittings and gaskets. I'm really wondering if both need to be replaced, or just one of them. That won't be that hard of a pill to swallow so long as they're not TOO hard to replace. I'll have to take the old ones off first to see what condition they're in.

Knowing how stealerships like to gouge at the Parts Dept., I guess that'* not to bad. Let us know how it turn out w/pics. I've only read of 2 oil line issues here, and both were done under warranty.

Is it possible that these oil line issues are a result of engine mounts breaking and excessive rocking of the engine back and forth?

Called Cadillac again to get an update

Wheel hub bearings are shot, and the wheels need to be balanced. The car is using the original tires and balancing, which was puts them in at 65,000 miles of life. I guess the original owner really babied this car. No wonder its having problems. Wow. However, I'll probably have someone else do that. The bearings are definitely covered by the warranty, so I hope they cover the diagnostic for that since there was indeed something wrong.

Coolant water crossover gaskets are gone. 6 hour job apparently. According to the service agreement, "water pump, fan and clutch, fan coupling, fan motor, radiator, oil pump case, and seals and gaskets" are covered. SCORE. ($112+ an hour x 6)

Steering gear is leaking. According to warranty, "steering gear housings and all internal parts, rack and pinion assembly..., ...power cylinder assembly and all internal parts" are covered under the warranty.

Front engine mount is broken. Also covered under warranty.

CV joints and tie rods apparently are just fine.

It will be really nice to drive the car again once the engine mount is fixed.

I would imagine a broken motor mount could cause enough drivetrain movement to cause the oil lines to leak. It seems one of the old members had both. Might have caused a couple of your problems. Are you sure that car didnt get in a wreck or jump railroad tracks? Sure alot of Forum 1st time problems with it. But @ 65,000 miles it'* one of the higher mileage ones. I have tortured my engine mounts yet havent had a problem with them. Cant believe your OEM rubber has 65k on it. My first set of front RSA'* showed the wear bars at 18k, and the second set (Goodrich gForces went @ 17k. Still have the OEM on the rear looking like next spring will be it for them.

I wouldn't know if the car was wrecked in all honesty, but a carfax report on the car showed up clean with no records of any wrecks.

I'm also surprised that my OEM tires have that much life on them. Its really quite surprising.

Can I somehow get the oil cooler lines covered by the dealer if they were a result of the engine mount breaking?

I'd say you would be grasping at straw with that one. Incidental damage would be near impossible to prove out, and I doubt a warranty company would consider it even if if were. The legal language used in these contracts make each exactly what they are, covered and non covered. Some states have consumer laws which vary the contract so I cant speak with a sureness about this one.

No worries. I'm stuck with the bill for the cooler lines. Oh well. They better not leak a lot more than they already do till I can afford new ones.

On another note though, I got a call back from Cadillac.

The good news is that all the parts I'm replacing are covered. Tie rods were fine btw.

Here'* what'* wrong with the car:
Wheel hubs (the entire hubs, not just the bearings will be replaced)
Water pump housing
Steering gear
Front motor mount

Can you guess what the bill is at a Cadillac dealership?

$4200

Yeah, that'* right. 42 Benjamin on a warranty I paid $2400 for. Nice huh? Great part is, I've already chewed them out of $1200 on the last repair.

Now the bad news. Because of a claim this huge, they need a warranty inspector to come out and take a look at the car before they agree to pay it. And once they agree to pay it, they have to fork over $4200, but since its such a high bill, they need to write a corporate check, which means that it would take 30-40 days to clear (supposedly, according to Cadillac). As a result, Cadillac would need to release the vehicle without pay, which I don't know if they'll do. I'm still waiting on a call from the guy over at Cadillac for more info on this situation.

OUCH! If they dont want to release the car, call GM Consumer Help. They have always bent for me after a grrrrrrr or 2.