: People with the 2005+ Northstars: Do you have problems with oil leaks?



bob k
05-08-13, 02:46 PM
I'm wondering if anybody has had any problems with the Northstar engines leaking oil at the half case seal? Reason im asking is because we are in the market for a new Caddy, and trying to decide if we should try a newer Northstar or go with the 3.6 (and possibly deal with the timing chain stretch). We had a 97 SLS with 205K, but its really starting to show its age, and it leaks oil like crazy. You can see smoke come out from under the hood when you park the car, the half case seal is shot. Boss also has a 1999 STS, and it leaks oil at the half case seal as well. We really love these cars except for that issue, and would love to know if GM has finally fixed this problem on the newer Northstars, so im looking forward for some of you to chime in! Thank you in advance.

dkozloski
05-08-13, 02:55 PM
My '06 Northstar with 55K miles doesn't leak a drop.

1BadCadSTS
05-08-13, 03:57 PM
I think you mean to ask about the 3.6 they drink oil not the LH2 N*

curtc
05-08-13, 04:01 PM
The half case seal leak does still happen on the redesigned N*....But it isn't nearly as common as it was in the FWD variation, I've only seen a few threads regarding that in here.

As far as the 3.6 (both non-DI and DI variations) they not only like to stretch timing chains but they are much more notorious for drinking oil than the LH2 N* is...GM utilized a very poorly designed PCV system in those engines.

EChas3
05-08-13, 08:31 PM
My wife & I have had our V8's for 4.5 & 5 years and our garage floor has been dry the whole time except for one leaky water pump on my car years ago (and a few Winter car turds). We have driven over 100,000 miles and think very highly of the N*.

Her car was a Hertz rental and does burn a little oil; less than a quart in 10,000 miles. She goes strickly by the OLM, ignoring the annual oil change advice in the manual. She gets it changed with new Mobil1 when alerted (about every 18 months & 10k). I check it when she gets back from road trips and add a sip when it's low. (It's her car. Why fight forces of nature?)

My car was broken in by some wonderful person in northern Wisconsin who had the dealer change the oil 4 times at 3,000 mile intervals to break-in my N* for me. I have the service record. It now uses virtually no oil and I don't spare the throttle. See the 'sticky' thread at the top of the forum. It's true, this N* thrives on WOT & compression braking.

It's fun, too!

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As far as the 3.6 (both non-DI and DI variations) they not only like to stretch timing chains but they are much more notorious for drinking oil than the LH2 N* is...GM utilized a very poorly designed PCV system in those engines.

Members also report cam & ring issues. They aren't as frequent, but there's nothing like catestrophic oil loss to ruin a trip. This forum contains multiple such reports.

If you like the V6, that's fine, but do yourself well and check the oil often.

bob k
05-09-13, 11:41 AM
Thanks for your input. Its a bit frustrating because between the two engines you are deciding what kind of problems you are willing to tolerate. I didn't learn about the 3.6 oil consumption til now, and now im really averse to getting a GM car with the 3.6. Its frustrating because we really love the look of the Cadillac and there is nothing else on the market like it, but after our experience with the Northstar we are hesitant in having to deal with the half case seal again. Not an easy choice...

1BadCadSTS
05-09-13, 11:42 AM
LH2 is a rock even if the half case leaks is a small seeping nothing to worry about

curtc
05-09-13, 11:47 AM
Thanks for your input. Its a bit frustrating because between the two engines you are deciding what kind of problems you are willing to tolerate. I didn't learn about the 3.6 oil consumption til now, and now im really averse to getting a GM car with the 3.6. Its frustrating because we really love the look of the Cadillac and there is nothing else on the market like it, but after our experience with the Northstar we are hesitant in having to deal with the half case seal again. Not an easy choice...

I'd tolerate a weaping half case seal over worrying my timing chain might snap at 70MPH anyday....Let's see, buy some Mobil1 once in a while or buy a new engines if the valves bend and cylinder walls score...hard decision...

EChas3
05-09-13, 07:16 PM
Bob K can't shake the mis-information that the 2005 & up 4.6 Northstar uses excessive oil. IMHO, there is no real pattern of this, even when abused. Some examples will burn a bit but very few leak. Most engines burn a little, especiall when producing like power & torque.

It's only real shortcoming is that it only gets average mileage. (It was expensive to build, but that's moot now!)

curtc
05-11-13, 01:36 AM
It's only real shortcoming is that it only gets average mileage.

I average 20-22MPG per tank...I'll take that in a full size, 320HP V8 powered luxury car any day...

1BadCadSTS
05-11-13, 06:43 AM
He's awd as am I. 13.5 mpg average.

EChas3
05-11-13, 06:44 PM
^^^ I do not disagree. My wife & I took her car on a trip to visit Mom today and got 24.5 mpg. Once before trashing the rock-like Michelin Energy tires that hers came with, we ran a full tank at around 80 MPH (2,000 RPM) and got 25 mpg calculated.

As Curt observes, I'll take that. It's not bad considering the STS is a 2-ton Luxury Sport Touring Sedan with over 300 HP & 300 Ft/lbs Torque. But some competitors are a bit more stingy on gas. I know of a car costing about $80k that makes almost 400 HP & gets 30 mpg. I do not want to trade; even at $4, just $1,000 still buys 250 gallons of gas. "Not bad" is not a slam; it's merely OK.

1BadCadSTS
05-11-13, 07:30 PM
^^^ I do not disagree. My wife & I took her car on a trip to visit Mom today and got 24.5 mpg. Once before trashing the rock-like Michelin Energy tires that hers came with, we ran a full tank at around 80 MPH (2,000 RPM) and got 25 mpg calculated.

As Curt observes, I'll take that. It's not bad considering the STS is a 2-ton Luxury Sport Touring Sedan with over 300 HP & 300 Ft/lbs Torque. But some competitors are a bit more stingy on gas. I know of a car costing about $80k that makes almost 400 HP & gets 30 mpg. I do not want to trade; even at $4, just $1,000 still buys 250 gallons of gas. "Not bad" is not a slam; it's merely OK.

Your wife's is rwd and yours is awd correct?

The 273 rear in the base rwd v8 will net good mpg while the awd with its greater mass and 323 gearing will eat fuel like a fat kid eats cupcakes.

I don't mind it. The toys and power are worth the trade off to me. I've never had an Eco car, ever. Always a GM V8. Not to mention with PA winters and my other car an SLP SS Camaro I wanted something which would prove to be a tank in snow. My STS4 has passed many a SUV and truck stuck in snow.

dkozloski
05-12-13, 12:21 AM
My '06 AWD V8 STS gets 22-24 MPG when the weather warms up. If you spin the wheels to get going and slide them to stop the mileage drops accordingly.

jsiddall
05-12-13, 05:53 PM
Well, I have 190K miles on my '06 and it does leak oil a bit -- apparently from the cam covers because it is running down the side of the block onto the PS pump. I also see this starting on my 110K mile SRX, and even a bit on my 80K mile SRX. So yes, they will eventually leak enough oil to drip on your driveway, but not for a long time. Unlike my 140K mile '97 STS that burned/leaked about ten times as much

As for mileage, I have never seen 24 MPG on my 323 geared RWD STS, and right now it is averaging about 13 MPG with city driving. So safe to say mine eats fuel. Still, as others have pointed out, no one buys these to be miserly.

bob k
05-12-13, 09:31 PM
Bob K can't shake the mis-information that the 2005 & up 4.6 Northstar uses excessive oil. IMHO, there is no real pattern of this, even when abused. Some examples will burn a bit but very few leak. Most engines burn a little, especiall when producing like power & torque.

It's only real shortcoming is that it only gets average mileage. (It was expensive to build, but that's moot now!)

I think our definition of excessive oil use is a bit different. :D

107973

That is what has happened on our 97 Seville, and why we are shaky on getting another one because we wouldn't like to repeat this later. Both have over 200K miles and have absolutely nothing wrong with them, except for this. We drive our cars till the wheels falls apart. Oil consumption im not worried about, its the oil LEAK. :)

Our Caddy's get about 22-23 MPG with mix of city and highway driving, so its not too bad. Once however we drove back from Wisconsin and had filled up with Ethanol-free fuel, and we damn near got average 30 MPG on the way back. It was amazing what proper fuel would do. Too bad were in Illinois....

oldcaddybuyer
05-13-13, 09:56 AM
Get a N* while you still can. I'm still searching for a low mileage N*...

I sure hope the new STS...I mean CTS...has something to offer other than the 3.6DI. We are not enthused.

jsiddall
05-13-13, 10:12 AM
Get a N* while you still can. I'm still searching for a low mileage N*...

I sure hope the new STS...I mean CTS...has something to offer other than the 3.6DI. We are not enthused.

Something like twin turbo, say with 420 HP?

curtc
05-13-13, 10:57 AM
Get a N* while you still can. I'm still searching for a low mileage N*...

I sure hope the new STS...I mean CTS...has something to offer other than the 3.6DI. We are not enthused.

Just slap a supercharged vette motor in there again...Seems to work well with the current CTS-V :cool:

my_bro
09-24-13, 09:31 PM
I'm leaking at 115K. Can't exactly see where but think it's the case half in the rear. It leaves a little puddle.

chazglenn3
09-25-13, 09:06 AM
I'm coming up on 127K miles and no oil leaks or excessive burning so far. Big contrast to my previous generation STS's.

edoubble2082
09-26-13, 11:22 AM
My sts4 v8 1 sg leaks at 130k I know this isn't that common but it happens I bought mine because I thought the leaking/Hg problem was fixed after 05 (i have a couple threads right now regarding this )just somthing to think about good luck

johng99
09-26-13, 12:57 PM
Love my new (to me) N* STS - 2005 purchased with 21,000 original miles. I have driven it about 3.000 miles in the last month, and am really glad I bought this car while examples like this are still out there. Oil leaks, well I drove Mercedes Benzes for many years, and head gaskets were pretty routine on the inline 6's and not uncommon on the V8's especially when approaching 200,000 miles. I hope I don't have oil leak issues again, but I wouldn't be frustrated with small leaks after my MB issues, and even if I have to replace seals or gaskets, the costs are pretty low compared to doing these jobs on the premier german cars. So get that Cadillac, drive it hard and enjoy it, knowing you have just bought one of the great performance/luxury values out there.

ddalder
09-26-13, 01:19 PM
I recently had my engine serviced because of the case half seal. The shop tells me it's about 16 hours labour (I have an AWD so there is a little more time in mine) plus parts. Fortunately I had GMPP warranty that covered all but $100. Personally, I wouldn't shy away from the N* just for this reason. I love my car (except in the city the fuel economy is dreadful) and would not worry too much about a minor leak. As long as it's not a big leak, the cost of 16 hours labour can buy a lot of oil! Even when I had the leak, my oil consumption was minimal. I don't ever recall adding between oil changes, despite using the OLM which means longer intervals.

I have no interest in the 6 cylinder at all. My mother has one in her Enclave and I'm really not impressed. It's very low mileage and has already been in for some of the common items (including timing chain).

EChas3
09-26-13, 11:11 PM
There's not enough torque in a 3.6 V6 to launch more than 2-tons to 80 MPH like we want. What good is top end (i.e. HP) in the states, anyway.

achavez
09-27-13, 01:26 AM
05 N* w/86k miles. owned it for about 2 months now. no leaks. I have been under the car as well and all is dry and healthy so far

Charles Warren
09-27-13, 02:03 PM
140k+ no leaks. Replaced valve covers because I thought I had a leak turned out to be oil filter loose (somebody had to loosen it) but nice and dry. Diff has some hairy looking stuff but looks normal but I cleaned it off to see if it'll come back. Will update next oil change

Lifer
09-28-13, 10:26 AM
My '06 Northstar with 55K miles doesn't leak a drop.

My hard driven '06 with 85K is flawless. I get 22 MPG (under 80 MPH) and it is FAST.

curtc
09-28-13, 02:55 PM
109k here, no oil leaks or real usage issues at all, last oil change interval I think I added a 1/2 quart over like 10k...My two previous Northstars (95, 01) leaked a good bit, the 95 burned it up pretty good too. AVG'ing 20-21MPG per tank since I got her at 71k. Easily the best Northstar I've owned to date :thumbsup:

EChas3
09-29-13, 12:43 AM
My wife's has over 75k and mine has over 85k and the garage floor is clean & dry. Only rarely, after very spirited driving, does my oil level drop at all. Hers needs a bit every few months.

DG2
09-30-13, 11:07 PM
Well I have to jump in. 2005 V8 1SG AWD. 194,000 NYC miles. No leaks ever on ground but my head gasket seeping bit. I will add a quart at 2500 miles and I change oil when monitor hits 40%.

Car looks amazing. I just put new battery in and set of Michellin all season tires last week. Only major issue I have is I need new MRC struts. Having tough time justifying cost on a 9 year old car with nearly 200 k miles.

Great car to buy.

mjcaddy
10-01-13, 06:28 PM
Well I have to jump in. 2005 V8 1SG AWD. 194,000 NYC miles. No leaks ever on ground but my head gasket seeping bit. I will add a quart at 2500 miles and I change oil when monitor hits 40%.

Car looks amazing. I just put new battery in and set of Michellin all season tires last week. Only major issue I have is I need new MRC struts. Having tough time justifying cost on a 9 year old car with nearly 200 k miles.

Great car to buy.

wow 194k!!!! knock on wood man, I sold my 03 DeVille with 181k and it was leaking like crazy, you can actually smell it, take care of her!.

edoubble2082
10-01-13, 06:46 PM
wow 194k!!!! knock on wood man, I sold my 03 DeVille with 181k and it was leaking like crazy, you can actually smell it, take care of her!. you mean knock on engine or knock in engine jk lol

curtc
10-01-13, 07:03 PM
wow 194k!!!! knock on wood man, I sold my 03 DeVille with 181k and it was leaking like crazy, you can actually smell it, take care of her!. When I sold my 2001 STS at 234k she leaked pretty good too from the half case seal, had to add about a quart every 1000 miles or so. She still purred like a kitten as long as you kept up on the oil level. I sure do miss that car though, so much more comfortable for longer trips.

Guy.Seminerio
10-01-13, 10:20 PM
Do understand that NYC miles and miles elsewhere are VERY different. With every mile there is a significant amount of additional idling, and accelerating, and why not throw in braking and gear changes. 194k is quite impressive in ny for any car really.

curtc
10-02-13, 12:58 AM
Do understand that NYC miles and miles elsewhere are VERY different. With every mile there is a significant amount of additional idling, and accelerating, and why not throw in braking and gear changes. 194k is quite impressive in ny for any car really.

I delivered pizza in mine, full time :)

Never again...

Guy.Seminerio
10-02-13, 12:57 PM
Haha wow. My brother used to deliver pizza in the Nissan. Smelled horrible in there.

curtc
10-02-13, 02:01 PM
Haha wow. My brother used to deliver pizza in the Nissan. Smelled horrible in there.

Since 2005 a Cadillac has been delivering pizza for Domino's in my home town...I started the trend in my '95 STS part time for a second job, I then began working full time shortly after purchasing my '01...I left that gig in 2009, shortly after a co-worker purchased a '04 Deville, he has been delivering in that since...It's not every day you see a Caddy delivering your dinner :)

I actually had a guy reduce my tip at the door after he saw my car.

He says, "You drive a Cadillac!? You clearly don't need this."
I replied, "But sir, it is FAR from being paid for!"

:thumbsup: