Cadillac Northstar (275HP)

[GreenMachine]

I was refered to this site from "www.cadillacowners.com" about oil.

Currently the oil that goes into the Cadillac is Kendall GT-1 5w30 Sythetic Blend Oil (I'm not sure its the high mileage or high performance blend, I assume its the high mileage, get the oil changes done a local shop we know the mechinics at and they suggested it). All seems well and the engine runs great on it. Switched to it a few changes back. Searched the forum and it seems Kendall has a good product.

Was mainly just wondering what the opinion of the oil is and what oil is good for the Northstar. I don't have an oil comsumption problem like some complain about with the Northstar so I guess just stick with whats working now unless there is an oil that stands out in Northstars

If its the high mileage version I like the idea of haveing the SealMax additive.

Driving conditions are usually a long trip once or twice a year and the rest city and suburb driving. Live outside of Buffalo, NY so the low temperature can be an issue. Last couple of years been plenty of single digit days a negative morning sneaks in.

 

[GreenMachine]

should've mention the deville has about 84K on it.

 

[johnd]

Check the owners manual. I remember hearing that the Northstar can have consumption problems if the correct weight is not used. Oddly enough it has problems with oils that are too thick. Your current choice soulnds like a good one. What is the OCI?

 

[DriveHard]

From the little research I have done, the Northstar consumes oil because nobody stresses the motor, and the ring packs get gummed up. Suggestions I have seen range from using Auto-Rx regularly to using a motor flush to simply making a couple of trips to redline every week. Be sure to keep the car in a low gear on the high speed run to allow a high vaccuum peroid when you lift the accelerator.

 

[unDummy]

If something works, stick with it.

Or, try a 0w30 for the cold weather. Make a trip to Canada and pick up a trunk full of Esso XD3 0w30.

 

[mshu7]

I just read in another thread where a guy is using German Castrol 0w30 in his Olds Intrigue. The engine is that car is basically a Northstar with 2 cylinders cut off (3.5L DOHC 90* V6). He said he has 0 consumption.

See: http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;f=42;t=002715;p=1#000007

I believe GC is on sale at AutoZone for 3.99/qt currently.

 

[GreenMachine]

The average OCI is around 3-4 thousand miles. Since I convinced my dad to start using the synthetic blend, and learning about the GM EOLI (engine oil life indicator) we are starting to let it go longer between and based on what the EOLI reads. Usually we change it around the EOLI saying between 15-20% or when the light comes on if we "forget" about it. We figure thats enough buffer for what the manual calls dusty conditions. My father is one that believes in the 3000 mile for 3 month policy but I've slowly told him to let it run and wait till the car wants it done. So far he is accepting that times have changed and oil last longer.

As far the high reving goes, on the Cadillac forums its refered to as WOT treatment, Wide Open Throttle. The transmission shifts (when the shifter is locked in 1/2/3) at the point of redline or just before so your still able to get it high in the rpms but not break anything. I let off just before its about to shift and the engine gets a good vacuum going.

I've done it and the first time it had a big brown cloud come out the back, after the second and third it was all cleaned up and since I only do it once a month and there isn't a brown cloud anymore. I certainly do some creative driving when I want to use all the ponies though.

The manual says 0w30 for below zero application, 5w30 below zero and under 60 degrees fairenhieght, 10w30 for above zero and over 60 degrees fairenhight. It also states the use of synthetic oil is recommeneded for the 5w30 and 0w30 oils. It goes on to say not to use any other viscosity oils and names 20w-50 specifically as one not to use.

Thanks for the piece of mind guys! Sometimes what a manual says and what needs to be done don't line up with some companies, but it seems Cadillac hit the nail on the head with that section.

 

[Ray H]

"Kendall GT-1 High Performance Synthetic Blend" is a synthetic blend of around 50% or more Group III base oil, the rest being mostly Group II with perhaps some Group IV as correction fluid along with the additive package according to a past post from Terry (one of BITIG's resident qualified oil gurus). It's made by ConocoPhillips which also produces "Motorcraft Premium Synthetic Blend" for Ford, "Phillips 66 TropArtic Synthetic Blend", "Conoco Super All Season Synthetic Blend", and "76 Super Synthetic Blend". If these "various" ConocoPhillips motor oils sound a lot like very similar peas out of different pods, you're not far off. Except for Motorcraft, BITOG doesn't as yet have very many used oil analysis posted for the other ConocoPhillips brands noted above - but that didn't stop quite a few of us from hoarding up on the TropArtic Synthetic Blend while Dollar Tree Stores had the stuff for a buck-a-quart pre-Katrina. Sounds to me like your mechanic knows his oil and is selling you a good product at a fair price.

 

[J. A. Rizzo]

I used to drive a 94 Seville to work every day in what I would call "severe service" conditions, until my wife somehow demolished it in a grocery store parking lot. That's the best bang for the buck I've had as far as cars go. I miss all those ponies! Anyway, it lived its entire life on either Pennzoil, Valvoline, or Havoline 10w30 (whichever was cheaper) summertime, 5w30 wintertime, and it got changed as soon as the DIC said to change it. I used AC-Delco, Purolator Premium or Purolator PureONE filters. It ran like a racehorse from the time I bought it to the day it met its untimely demise, and that spanned 154k great miles. Under the oil filler cap, it was clean as a whistle just like new, even with 154k miles on it. I think you could put anything in that N* and it would run forever as long as you changed it when it said to change it. I used regular inexpensive oil and OEM or premium aftermarket filters just to be safe, and I would say that strategy worked perfectly. No synthetics or exotic oils required. Saved quite a few bux that way and the engine lasted a long time and would have gone a lot longer I'm sure.

 

[JohnnyG]

Boy, this topic won't be around long! No Japanese cars mentioned, no German cars either! Going by the OLM too! Unbelievable! Such heresy will not be tolorated.

Remember, second gear ONLY on the WOTs

 

[JohnnyO]

Welcome to BITOG!
I look after my parents' Caddys, mom's 99 and dad's 04. The older Northstars with flat-tappet lifters are happier with 10w30. The newer roller-lifter engines are spec'd for 5w30. As cold as it gets in Buffalo, I'm through there once or twice a month, I'd run 5w30 in the winter and 10w30 the rest of the year.
I use Mobil 1 in both my parents' cars, go by the OLM in dad's and once a year in mom's (the OLM is usually down to 30%), figuring the full synthetic will not gum up the rings as much.
Here is my Used Oil Analysis, you will learn about these here

, from my dad's car with 11,200 miles on Mobil 1 Extended Performance, it's very good.

http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;f=3;t=003068

Thing to remember, a Caddy N* holds 7.5 quarts, so the oil doesn't wear out as fast as in other cars that hold less. Even conventional oil would be good for 7000 in a N*.

 

[Moloch]

I dont think he can redline the car too much, its an automatic that shifts for him. I would reccomend somethign with 0W-X rating, It gets very cold in Buffalo.

 

[GreenMachine]

Great stories in here. If we were to take it to the dealer they would use a Mobil 1 in it. We take it to the local shop simply because it’s right down the road.

Funny story is my dad got a coupon for a 9.99 Oil change at the usual place. Well we tried using the coupon but the guy told us "that’s for the no-name brand and I couldn't put that stuff in that car and feel ok with it" He also said that it does take more than the average car oil wise to fill. We were skeptical, but the brand on the "no-name" oil doesn't ring any bells with the oil you guys talked about so I guess he was right. He also said they usually switch a lot of their customers to 5w30 for the winter. It’s a Napa place so that’s the oil filter that gets put on. From my searches on the forum they're pretty good.

As far as American cars go, I've grown up around them since I was born (in 1988, 18 in January), first car I rode in was a 1985 Pontiac Parisienne (that was a big rear-wheel drive monster sedan), then came an 88 Oldsmobile Delta88, the one with the giant doors on each side, after that a 1992 Deville and now this 98' Deville. All have gone beyond the 100k mark except the 92 (and that I'll get into), and the only one that we traded away not running was the Olds and my dad was a traveling salesmen who drove the **** out of them.

The 92' Deville only left us because it was totaled in a front end collision, somebody with a van ran a red-light making a left turn, my father hit them on an angle and the front right was destroyed and windshield cracked, my dad was able to drive it home but the cost to fix was over its worth. It was already up in the 90K range and showed no signs of quitting. Somebody who was in a rear-end collision bought it and swapped the parts from theirs to it so it might still be cruising somewhere.

Thanks for all the info, my minds a sponge so I'm sure I'll be passing all this along to other Cadillac owners. The Northstar is a great engine system and takes a lot of abuse and loves to run. For a sedan this size it’s fast and surprisingly fuel efficient, and its fun to beat the 4-bangers of the line who have stickers and spoilers who think it’s an even fight. I'd like to see Cadillac and a litre of displacement to the rear drive versions, although 320 horses is still nice. Those are another discussion altogether.

 

[Alex P.]

I'd agree with Johnny, 10w30 seems to do better in the older Northstars. I've been using Havoline or Castrol GTX 10w30 in my sister's 97 Deville. Some of them burn more oil than others, and I know it is NOT just because they're not being driven hard. Not every N* is built equal. Hers eats 2-3 quarts between changes, but it's pretty clean and runs strong. Top off keeps the oil in good shape

. Also, with the filter, it takes closer to 8 quarts.

They're pretty reliable if you keep after them, but they're a lot less forgiving about maintenence transgressions than other GM motors I change the oil on. Not that I would personally let our cars go poorly maintained, but I've seen a LOT, and I mean a LOT of dead Northstars at Pohanka Cadillac just lying around back around the bays.

Err, although I'd question the fuel efficiency part, in relation to the size and weight of the vehicle. It's decent for the performance of the engine, but I got considerably better mileage in my Caprice with a 4bbl 305. Not to mention I ran at most 89 octane in that, while you have to use minimum 91 octane in a Northstar (only 87/89/93 is available here).

[ December 14, 2005, 12:51 PM: Message edited by: Alex P. ]