need info on 1999 cadillac deville engine
Cadillac
 

Cadillac Forums | Help Us Help You | Advertise | Cadillac Parts | Cadillac News | Cadillac Classifieds / (Old System)

Cadillac Technical Archive | Cadillac Dealers | Cadillac Reviews | Cadillac Dealer Reviews | Cadillac Vendors

CadillacForums.com is the premier Cadillac Forum on the internet. Registered Users do not see the above ads.
+ Reply to Thread
Results 1 to 12 of 12
Northstar Engines and System Technical Discussion Discussion, need info on 1999 cadillac deville engine in Cadillac Engine Technical Discussion; We are lookign at pruchasing a 1999 Cadillac Deville from another person who has kept it well maintained. It has ...
  1. #1
    debbouk is offline Cadillac Owners Member
    Join Date
    Nov 2005
    Posts
    2

    need info on 1999 cadillac deville engine

    We are lookign at pruchasing a 1999 Cadillac Deville from another person who has kept it well maintained. It has 95,000 miles. Our mechanic told us he had heard there had been problems with this model with the engine having to be replaced around 125,000 miles at a cost of $6,000-$8,000. Our present 1994 cadillac has 350,000 miles, no engine problems (not northstar). Has anyone else heard of problems with the northstar engine in later models? Thank you!

  2. Remove Advertisements
    CadillacForums.com
    Advertisements
     

  3. #2
    mtflight's Avatar
    mtflight is offline Cadillac Owners Connoisseur
    Automobile(s): 1999 White Diamond ETC
    Join Date
    Jan 2005
    Location
    Dallas, TX
    Posts
    2,526

    Re: need info on 1999 cadillac deville engine

    If the cooling system has been maintained and the car has never overheated--there are no inherent problems with the Northstar.

    It's an aluminum engine so overheating it can toast the head gaskets and headbolts.

    There are plenty of older Northstars on the road, especially on DeVilles... look on the highway, or at the grocery parking lot--many are high mileage.

    My mechanic said he's worked on at least 5 that have over 300,000 miles and the only maintenance was cooling system and changing the oil.

  4. #3
    bubba67801 is offline Cadillac Owners Member
    Join Date
    Mar 2005
    Location
    Dodge City, KS
    Age
    53
    Posts
    40

    Re: need info on 1999 cadillac deville engine

    I agree, it is a fine car and engine if you keep up with the cooling system and change oil. I would keep the info center on coolant temp and watch it all the time. Mine normally runs 195F-210F. Fans kick on at 222F unless A/C is on then fans will run. Computer on car won't tell you its overheated until around 260F.

    Personally, I think with the aluminum engine that is to high. If I got to 245-250F I would pull over and turn off engine to cool it down then look for any problem. Because once the aluminum engine gets to hot, its probably too late for your head gaskets.

    Here is where some people will disagree with me: I say use a synthetic oil like Mobil 1. Why? Less friction means less heat and that can only help the cooling system cool the engine and the oil itself will help with engine cooling. Others will probably tell you that synthetic oil is a waste of dollars...I say, you decide.

  5. #4
    mtflight's Avatar
    mtflight is offline Cadillac Owners Connoisseur
    Automobile(s): 1999 White Diamond ETC
    Join Date
    Jan 2005
    Location
    Dallas, TX
    Posts
    2,526

    Re: need info on 1999 cadillac deville engine

    Quote Originally Posted by bubba67801
    Here is where some people will disagree with me: I say use a synthetic oil like Mobil 1. Why? Less friction means less heat and that can only help the cooling system cool the engine and the oil itself will help with engine cooling. Others will probably tell you that synthetic oil is a waste of dollars...I say, you decide.
    Sounds good at least in theory. I wonder how much cooler it would run though? I was putting in the Valvoline Synthetic Max Life in mine (75K and over), until I read on the forum that synthetic was unnecessary, and not reccomended for oil seepage.

    I used to lose more oil then, but I also had an oil cooler line that was leaky. Now the bottom of the engine is "relatively" dry... no leak... but it is moist. I usually have to add a quart between oil changes (per the monitor which run around every 7K miles).

    I'll try synthetic again, for experimental reasons (keeping an eye on temperature). Would a free-er breathing exhaust help keep engine temperature down? I'm looking for excuses to get more sound.

  6. #5
    bubba67801 is offline Cadillac Owners Member
    Join Date
    Mar 2005
    Location
    Dodge City, KS
    Age
    53
    Posts
    40

    Re: need info on 1999 cadillac deville engine

    Quote Originally Posted by mtflight
    <snip> Would a free-er breathing exhaust help keep engine temperature down? I'm looking for excuses to get more sound.
    It should, as it would create less back pressure. The only thing I would worry about in doing so would be if your state has emission standards and inspections that you do it in a way that you still are able to pass emissions testings.

  7. #6
    phathead785's Avatar
    phathead785 is offline Cadillac Owners Fanatic
    Automobile(s): 1996 Cadillac Deville, 2004 Cadillac DTS, 2011 CTS AWD Coupe
    Join Date
    Aug 2005
    Location
    Boston MA
    Age
    25
    Posts
    328

    Re: need info on 1999 cadillac deville engine

    So would you say my 96 deville is toast because it over heated? It happened about 3 months ago and nothing seems wrong- what do you think?

  8. #7
    Ranger's Avatar
    Ranger is offline Cadillac Owners Member
    Automobile(s): White Diamond '03 DHS (with floor shift)
    Join Date
    Jun 2004
    Location
    Woodstock Ill.
    Age
    66
    Posts
    70,504

    Re: need info on 1999 cadillac deville engine

    Depends on how badly it overheated. If it is running fine and is not overheating or loosing coolant, your probably ok.

  9. #8
    mgb4tim's Avatar
    mgb4tim is offline Cadillac Owners Member
    Automobile(s): 1999 Deville
    Join Date
    Oct 2005
    Location
    Pennsylvania
    Age
    47
    Posts
    88

    Re: need info on 1999 cadillac deville engine

    My 99 is at the dealer right now to get new head gaskets. They thought the original leak was the water pump and crossover gaskets. The next day, coolant level was low, again. Next day, complete meltdown; coolant level dropped so fast, the check coolant level message didn't even appear, but it did tell me to stop the engine and change the oil.
    so, I fried it. Dealer is repairing for free, since I haven't had the car for a week when the leak started. We're still wondering what the original source of the coolant leak was. Maybe another part of the head gaskets. He tells me they lift it, drop the front sub-frame, and pull the engine/trans from underneath - a $2k job. My deductible=$100, so with 80k miles, close enough for a coolant replacement and was time for an oil change anyways.
    I drive 125 miles a day for work, so we'll know right away if the leak is fixed once I get it back. They gave me an '03 Seville as a loaner, which I've had for a week already, but I like my Deville better.

  10. #9
    cl1986's Avatar
    cl1986 is offline Cadillac Owners Connoisseur
    Automobile(s): 94 Eldorado, 94 SLS got crushed
    Join Date
    Jun 2003
    Location
    South Dakota
    Age
    35
    Posts
    1,485

    Re: need info on 1999 cadillac deville engine

    I highly doubt the synthetic oil will lower the temp of the engine.

    Seeing how the radiator cools the engine along with the thermostat, either way you will run at 220 no matter what. My car runs at 220 in -20* and at 220 in 110* in the summer. The cooling system controls the temp, so theres no way oil will keep it cooler. Even if it did, the thermostat would stay closed and heat it up anyway!!!!

    Also, even if it were true, you dont want your car running at a lower temp, this causes poor gas milage and other abnormal wear. Just ask some guys that replaced their thermostat with a 165* one and have a computer car or truck, IE. chevy 350.

  11. #10
    mtflight's Avatar
    mtflight is offline Cadillac Owners Connoisseur
    Automobile(s): 1999 White Diamond ETC
    Join Date
    Jan 2005
    Location
    Dallas, TX
    Posts
    2,526

    Re: need info on 1999 cadillac deville engine

    Quote Originally Posted by cl1986
    I highly doubt the synthetic oil will lower the temp of the engine.

    Seeing how the radiator cools the engine along with the thermostat, either way you will run at 220 no matter what. My car runs at 220 in -20* and at 220 in 110* in the summer. The cooling system controls the temp, so theres no way oil will keep it cooler. Even if it did, the thermostat would stay closed and heat it up anyway!!!!

    Also, even if it were true, you dont want your car running at a lower temp, this causes poor gas milage and other abnormal wear. Just ask some guys that replaced their thermostat with a 165* one and have a computer car or truck, IE. chevy 350.
    Good observations.

    I was going to add a quart of synthetic, but it's very hard to justify the price difference. I'll stick to my Mobil 5000.

  12. #11
    Navy Senior is offline Cadillac Owners Member
    Automobile(s): 1999 Cadillac Devile
    Join Date
    Oct 2011
    Location
    Stratford, NJ
    Posts
    1

    Re: need info on 1999 cadillac deville engine

    Good evening Debbouk,

    I have recently purchased a 1999 Cadillac Deville. I was warned that the Engine will blow a head gasket. Well they were right. Due to the heads being aluminum and the bolts that hold the head in are steel, the threads on the heads give way and you blow a gasket. I was told that is the only issue with the Northstar motors. Now while taking my engine apart, my mechanic showed me the inside of my engine. He stated it was a very clean engine and shows that it was well taken care of and I should not have ANY more problems. I know I am not a mechanic and don’t know too much, but I thought I would share with you the problem I encountered. I hope all works out for you.

  13. #12
    maeng9981's Avatar
    maeng9981 is offline Cadillac Owners Connoisseur
    Automobile(s): 14 SRX, 12 Sierra, 00 SLS, 99 Deville 50-year Anniversary
    Join Date
    Mar 2009
    Location
    Dallas, TX
    Age
    22
    Posts
    2,921

    Re: need info on 1999 cadillac deville engine

    This is an ancient thread.

    Also not all Northstars blow their head gaskets / lose head bolt clamping force. The "root cause" of a failed one is still not very clear, and there are still plenty on the road with factory head bolts/gaskets.

Quick Reply Quick Reply

Register Now

Please enter the name by which you would like to log-in and be known on this site.
If you do not want to register, fill this field only and the name will be used as user name for your post.

Please enter a password for your user account. Note that passwords are case-sensitive.

Please enter a valid email address for yourself.

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Bookmarks

Cadillac Posting Rules

  • You may post new threads
  • You may post replies
  • You may not post attachments
  • You may not edit your posts
Read about Lincoln | Buick | Kia Forte Forum
Need products for your Cadillac? Check out your options at the links below:

custom floor mats | Cadillac Chrome and Black Chrome Wheels | window tinting