Coolant flush and change...Would you? - Page 2
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
Page 2 of 2 FirstFirst 1 2
Results 16 to 30 of 30
Like Tree2Likes
Cadillac STS Forum - 2005 through 2012 Discussion, Coolant flush and change...Would you? in Past Cadillac Vehicle Discussion; Originally Posted by MoistCabbage The original point of DEX was indeed for it to be a long life coolant. However, ...
  1. #16
    wake's Avatar
    wake is offline Cadillac Owners Enthusiast
    Automobile(s): 2007 STS-V, 2005 Escalade
    Join Date
    Sep 2003
    Location
    Stafford, VA
    Posts
    560

    Re: Coolant flush and change...Would you?

    Quote Originally Posted by MoistCabbage View Post
    The original point of DEX was indeed for it to be a long life coolant. However, many green coolants are rated for the same 5 years/100K miles, even 10 years ago this was true.

    AND, regardless of what the bottle says, 5 years is a lot to ask of any coolant. Most would recommend a drain and fill every 2-3 years. And a flush is not necessary. The point of changing the coolant is to replenish the anticorrosive additives. A drain and fill served that purpose just fine, even if draining leaves a small amount of old fluid in the system.
    I couldn't tell you about the green stuff made 10 years ago, the last GM I had that used the green stuff was my 88 Camaro, back then it was 2 year intervals from the maintenance schedule. Everything I've owned since then has been Dex filled from the factory.

    I understand about replenishing the anti-corrosive properties being the reason for changing the coolant, the 5 year interval seems to be fine though on Dex. I've never had a problem sticking with it. I've had 4 Northstars among the various other engines, using the recommended interval never caused me any issues. No radiators, no heater cores, no water pumps have been lost to corrosion using the manufacturer recommended intervals in any of my vehicles.

  2. #17
    EChas3's Avatar
    EChas3 is offline Cadillac Owners Master
    Automobile(s): 2006 STS4 V8 1SG & 2007 STS V8 1SE
    Join Date
    Jun 2008
    Location
    Cedarburg, WI
    Age
    57
    Posts
    7,372

    Re: Coolant flush and change...Would you?

    I've had mechanics tell me radiators all just go bad, regardless of flush & fill maintenance. After having several cars for extended miles, I think they just want to sell radiators.

  3. #18
    ddgm is offline Cadillac Owners Fanatic
    Automobile(s): 2005 STS
    Join Date
    Jun 2009
    Location
    Hamilton, ON & Fort Myers, FL
    Posts
    234

    Re: Coolant flush and change...Would you?

    My son has a 2002 Seville STS that had the dreaded HG problem. Being as how he still works and I don't. I arranged to have it repaired by Northern Performance. He pulls the engine, replaces the headbolts with his own studs, and reassembles for $2500.00. He has done hundreds of these, so he says. What I am getting at here is, he gives a 100,000 mile, 5 year warranty as long as you use the "green" anti-freeze and replace it every 2 years. He thinks dex-cool was one of the causes of the HG nightmare.
    After all this, I still chose to flush and replace with dex-cool for my 2005 STS.

    Doug

  4. #19
    turnne is offline Cadillac Owners Connoisseur
    Automobile(s): Cadillac STS
    Join Date
    Oct 2007
    Age
    50
    Posts
    1,010

    Re: Coolant flush and change...Would you?

    Quote Originally Posted by ddgm View Post
    My son has a 2002 Seville STS that had the dreaded HG problem. Being as how he still works and I don't. I arranged to have it repaired by Northern Performance. He pulls the engine, replaces the headbolts with his own studs, and reassembles for $2500.00. He has done hundreds of these, so he says. What I am getting at here is, he gives a 100,000 mile, 5 year warranty as long as you use the "green" anti-freeze and replace it every 2 years. He thinks dex-cool was one of the causes of the HG nightmare.
    After all this, I still chose to flush and replace with dex-cool for my 2005 STS.

    Doug

    I doubt VERY seriously that dex Cool was part of the Northstar HG issue...

    It was a design flaw..IMO...and one that , even after updates, continued for about a decade

    Though ..on another note ..I rarely hear about 02( and later) cars having issues with them


    Warren

  5. #20
    MoistCabbage's Avatar
    MoistCabbage is online now Cadillac Owners 10000+ Posts
    Automobile(s): Crimson 2001 Seville STS, 1990 Seville (RIP)
    Join Date
    Sep 2010
    Location
    East Boston MA.
    Age
    26
    Posts
    21,979
    DEX had NOTHING to do with the HG issue. Why were there HG failures before '96, before DEX? Why don't all '96+ GM vehicles have HG issues? Do some research in the Northstar forum on the root causes of failure.

    FWIW, there is nothing significant about '02. In '00, a change was made to longer head bolts, and changes were made to the block casting process, GREATLY reducing the likelihood of an issue. In late '04, a change was made to coarse thread head bolts, virtual eliminating the problem.

  6. #21
    ddalder's Avatar
    ddalder is online now Cadillac Owners Connoisseur
    Automobile(s): 2008 STS-4 N* 1SG
    Join Date
    Aug 2008
    Location
    Canada
    Posts
    1,953

    Re: Coolant flush and change...Would you?

    Quote Originally Posted by MoistCabbage View Post
    FWIW, there is nothing significant about '02. In '00, a change was made to longer head bolts, and changes were made to the block casting process, GREATLY reducing the likelihood of an issue. In late '04, a change was made to coarse thread head bolts, virtual eliminating the problem.
    Depending on which Northstar you're talking about, the change was before late 2004. All LD8's for 2004 model year vehicles and beyond cars have the coarse thread. This will cover any Deville, Seville or Bonneville GXP. Any of the Caddy's with the L37 in 2004 may or may not have had the coarse thread.

  7. #22
    Charles Warren's Avatar
    Charles Warren is offline Cadillac Owners Fanatic
    Automobile(s): 2006 sts v8 and 2003 cts 3.2
    Join Date
    Nov 2011
    Location
    Atlanta, Georgia, United State
    Age
    86
    Posts
    428

    Re: Coolant flush and change...Would you?

    Quote Originally Posted by MoistCabbage View Post
    Changing the coolant will NOT make the engine run any better.

    Coolant system cleaner is only needed in SEVERELY neglected systems. And in the case of aluminum engines, pretty much never. There's no chance of rust forming sludge and coating anything.
    i guess im crazy lmao but in my 2000 dts which had low miles when i got it i did a flush and guess what the coolant wasnt even nasty but the heat was hotter sooner the car ran smoother and believe it or not felt much peppier so if you deplete the coolants ability to perform its job regarless of what it looks like it will make your car run a lil sluggish been doing this for a min i thought my buddy at midas was pulling my leg but ever since then ive been draining my coolant every year. did cts same way and that car has 240k and runs like a singer sewning machine. and my gtp is cast iron and ive seen so many 3.8s with the dex soup mix yukkkk my ex gf gtp never came clean after i flush it 3 times so i said forget it drop fluid every year on hers(not anymore shes an ex)

  8. #23
    R/T kota's Avatar
    R/T kota is offline Cadillac Owners Fanatic
    Automobile(s): 2006 STS 4, 67 Firebird, and a pair of SS Impalas
    Join Date
    Jul 2013
    Location
    Hamilton Ontario Canada
    Age
    44
    Posts
    112

    Re: Coolant flush and change...Would you?

    Engine temp plays a big roll in how a late model computer controlled engine will run.
    Lowering the engine temp on my old truck by 15 degrees made it run 2 tenths quicker in the 1/4 mile.

  9. #24
    wake's Avatar
    wake is offline Cadillac Owners Enthusiast
    Automobile(s): 2007 STS-V, 2005 Escalade
    Join Date
    Sep 2003
    Location
    Stafford, VA
    Posts
    560

    Re: Coolant flush and change...Would you?

    Quote Originally Posted by EChas3 View Post
    I've had mechanics tell me radiators all just go bad, regardless of flush & fill maintenance. After having several cars for extended miles, I think they just want to sell radiators.
    They do seem to go bad, but not due to corrosion. I've never lost a radiator in a newer vehicle to corrosion but have had to replace them due to cracks in the plastic tanks that seemed to develop after 10+ years (heat cycling maybe?). When I pulled the radiators the guts always looked like new in the old ones. That's one thing I miss about my 70s and early 80s vehicles, all metal radiators.

    ----------

    Quote Originally Posted by MoistCabbage View Post
    DEX had NOTHING to do with the HG issue. Why were there HG failures before '96, before DEX? Why don't all '96+ GM vehicles have HG issues? Do some research in the Northstar forum on the root causes of failure.

    FWIW, there is nothing significant about '02. In '00, a change was made to longer head bolts, and changes were made to the block casting process, GREATLY reducing the likelihood of an issue. In late '04, a change was made to coarse thread head bolts, virtual eliminating the problem.
    I was skeptical about the head gasket issue at first but I've had 3 pre-05 Northstars, all maintained and none ever had head gasket or the pulled thread problems. They were all driven hard too, WOT runs several times a week getting on the L.A. freeway system (gotta love those stop lights at the bottom of freeway entrance ramps). Kept them to 100K+ miles except the 03 I owned, traded that one in at 93K miles.

    All the stories I read about head gasket or pulled block threads had one common theme, either never changed the coolant or didn't know if it had ever been changed on a used car.

  10. #25
    EChas3's Avatar
    EChas3 is offline Cadillac Owners Master
    Automobile(s): 2006 STS4 V8 1SG & 2007 STS V8 1SE
    Join Date
    Jun 2008
    Location
    Cedarburg, WI
    Age
    57
    Posts
    7,372

    Re: Coolant flush and change...Would you?

    The are some interesting write-ups claiming to 'prove' that GM rushed DEX into cars with head gasket materials not qualified for the combination of chemistry & heat cycles. Add a block stud thread pitch more suited to cast iron than aluminum and higher compression with only knock control between engine damage and bad gas.

    What do you get? That beautiful WOT throttle sound and burnt DEX out the tailpipe. Isn't it ironic they designed the Northstar to run even after catastrophic coolent loss?

  11. #26
    curtc's Avatar
    curtc is offline OCD - Obsessive Cadillac Disorder
    Automobile(s): White Diamond 06 STS V8 RWD 1SF F55 HUD/ACC NAV - 130k
    Join Date
    Jul 2005
    Location
    Burnsville, MN
    Age
    29
    Posts
    5,554

    Re: Coolant flush and change...Would you?

    Quote Originally Posted by EChas3 View Post
    Isn't it ironic they designed the Northstar to run even after catastrophic coolent loss?
    I always thought that was odd myself, it's almost like they knew the issue was present and designed a nifty, little workaround to protect the engine from being completely ruined.
    Past Cadillac's

    2004 CTS 3.6L - 2011-2012
    2001 Seville Touring Sedan - 2006-2011
    1995 Seville Touring Sedan - 2005-2006

  12. #27
    EChas3's Avatar
    EChas3 is offline Cadillac Owners Master
    Automobile(s): 2006 STS4 V8 1SG & 2007 STS V8 1SE
    Join Date
    Jun 2008
    Location
    Cedarburg, WI
    Age
    57
    Posts
    7,372

    Re: Coolant flush and change...Would you?

    Although it is still completely ruined. It's just in your driveway smoking.

  13. #28
    Charles Warren's Avatar
    Charles Warren is offline Cadillac Owners Fanatic
    Automobile(s): 2006 sts v8 and 2003 cts 3.2
    Join Date
    Nov 2011
    Location
    Atlanta, Georgia, United State
    Age
    86
    Posts
    428

    Re: Coolant flush and change...Would you?

    I still love northstars. Had only 1 overheat out of 8 but in 3.8L(231 buick v6) I tore up every last one of em I've had, smh 4 gtps 1 Bonneville they dont handle stress as well as most think but tell you a 32v northstar is a pos. sorry but i love 4.6 dohc but will admit 3.8 is easily modded and cheaply

  14. #29
    EChas3's Avatar
    EChas3 is offline Cadillac Owners Master
    Automobile(s): 2006 STS4 V8 1SG & 2007 STS V8 1SE
    Join Date
    Jun 2008
    Location
    Cedarburg, WI
    Age
    57
    Posts
    7,372

    Re: Coolant flush and change...Would you?

    I really do agree. The HG failure is just so disappointing in an otherwise outstanding powerplant.

  15. #30
    cadillacmike68's Avatar
    cadillacmike68 is offline Cadillac Owners Connoisseur
    Automobile(s): 68 DVC, 96 FLTWD Brg, 09 STS N* Platinum, 11 CTS Premium
    Join Date
    Jan 2005
    Location
    Left the desert - Back in FL
    Age
    53
    Posts
    1,072

    Re: Coolant flush and change...Would you?

    I do it myself on my older cars and my wife's CTS still has free scheduled maintenance. For the STS - It's due next year. If I can find a place to put the flushing attachments and drain point(s), i'll do it myself. If not, then a good tire shop is right across the street from my development, and they have some good people there. The dealer will do a fine job as well and will give me a free rental for the day, so I'll compare the prices and details of what they do.

    Certain things are really dealer only, but cooing system flushes are not one of them.

    And if anything with silicates is used, you are basically back to flushing every 2 years. It gets into the metal.

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