: '95 Eldo: how much life left



Verbal
11-09-10, 02:05 PM
Howdy.

My folks have a 1995 Eldorado (non-ETC) with less than 40k on the odo. It is the classic retiree special, driven mainly to go to the store or across town to visit the grandkids. Other than a couple of minor cosmetic issues, it looks straight off the showroom floor. It's even painted in Retirement Gold (not sure if that is the official Cadillac color name).

I'm familiar with the head bolt and head gasket issues these cars have. I'm wondering how much more service life he can expect from the engine before it grenades.

Also, what is the general consensus on giving these engines the Italian Tune-up? Since he does mainly around town driving, would it be a good idea for me to borrow the car one day and do the wide open throttle sprint up the on ramp to clear out the carbon?

Thanks!

vincentm
11-09-10, 02:29 PM
Less that 40K? first thing id do is get a block test done, and/or even if it doesnt have a HG problem, get it studded. with less than 40K that ride is a definite keeper

Submariner409
11-09-10, 02:34 PM
As with any other mechanical apparatus, maintenance is the determining factor in "life". The head gaskets (or anything else) may go in a few minutes or never. Is the base 1995 a 4.9 GM or a 4.6 Northstar ??

Read the entire Cadillac Technical Archive up in the black bar - the whole thing and the article "Occasional full throttle acceleration............"

If the car has had a sedentary life, work it up to full power gradually - just like a human, laziness leads to clogged arteries and it takes some exercise to get things moving again. Keep a close eye on the oil level (in the bottom 3 X's on the dipstick) and the coolant level - reservoir half full, cold. if you/they have not done a coolant change within the past 3 years, do it now. The car came with green low-silicate coolant installed.

EDIT: "get it studded" is a $3,500 job for a non-wrencher. If it ain't broke, don't fix it.

vincentm
11-09-10, 02:54 PM
EDIT: "get it studded" is a $3,500 job for a non-wrencher. If it ain't broke, don't fix it.


Just had to throw that in there, because that's what'd id do, but then again im super obsessed with these Eldorados :alchi:

Verbal
11-09-10, 03:03 PM
It is a Northstar engine. I believe all '95 Eldos came with one of the two Northstar flavors.

They have always been good about routine maintenance.

What is the problem with low-silicate coolant in these engines?

Thanks, I'll check out the stickies.

vincentm
11-09-10, 03:08 PM
It is a Northstar engine. I believe all '95 Eldos came with one of the two Northstar flavors.

They have always been good about routine maintenance.

What is the problem with low-silicate coolant in these engines?

Thanks, I'll check out the stickies.


Dex-Cool is the suspect in which the Ethylene Glycol might deteriorate the gaskets...i could be wrong though...

Ranger
11-09-10, 05:08 PM
even if it doesnt have a HG problem, get it studded.
That's like getting a quadruple bypass now because you MAY need it someday. I'm with Sub. Fix it when and IF it needs it. Nothing wrong with being obsessed. Just don't let your obsession do your thinking for you.

Dex has been blamed for lots of things, but it is not the cause of the head gasket failure.

Submariner409
11-09-10, 05:10 PM
Dex-Cool is the suspect in which the Ethylene Glycol might deteriorate the gaskets...i could be wrong though...

DEX-COOL is an ethylene glycol coolant; so is green goddess. The DEX uses a different acid chemistry for its additives. Low-silicate or No-silicate is standard for today's green coolants. Read the labels.

I believe the change to DEX- came in 1996.

There is nothing wrong with DEX and there is nothing wrong with green - you simply have to change them religiously, and few people actually do that.........

vincentm
11-09-10, 06:26 PM
That's like getting a quadruple bypass now because you MAY need it someday. I'm with Sub. Fix it when and IF it needs it. Nothing wrong with being obsessed. Just don't let your obsession do your thinking for you.

Dex has been blamed for lots of things, but it is not the cause of the head gasket failure.


So is it the threads that cause the problem? Mainly the aluminum block and torque?

vincentm
11-09-10, 06:28 PM
DEX-COOL is an ethylene glycol coolant; so is green goddess. The DEX uses a different acid chemistry for its additives. Low-silicate or No-silicate is standard for today's green coolants. Read the labels.

I believe the change to DEX- came in 1996.

There is nothing wrong with DEX and there is nothing wrong with green - you simply have to change them religiously, and few people actually do that.........

Wouldn't the acidity lead to gasket deterioration faster than the green coolant? Not trying to talk like i know but just trying to learn.

Ranger
11-09-10, 08:56 PM
That's the chicken or egg question, but I'm pretty much sure it the threads that pull first.

Don't take the "acid" too literally in Organic Acid Technology coolant. It does not eat gaskets.

tateos
11-10-10, 01:58 PM
As someone who has done a HG job, I think the gasket leaks first, maybe just a little, then coolant and combustion gases enter the head bolt holes, combine to form a corrosive soup, and over time the aluminum threads corrode/erode, and then they let go and clamping pressure is lost. All of this might go on for years with no symptoms, but once the threads let go, now the combustion gases can enter and overpressurize the cooling system, force out the coolant, and Voila!: Massive Overheating.

That might not be descriptive of all N* HG failures, but I think it's the most common scenario.

Pete1996
11-10-10, 04:00 PM
We now have my parents 1996 STS and I would say that they did not baby it, both are not afraid to drive fast however I'm willing to bet that they never used WOT or caused the trans to downshift hard to wind it out.
It had about 140K miles when they gave it to us, and began using coolant at about 1/2 gal/yr or 10K miles. We are now at 160K miles and it is using about 1/2 gal of coolant every 2000 miles. I believe that this is due to the HGs slowly failing. It runs hotter than I like when low on coolant but has never overheated or even gone into the red.

I have to wonder if WOT to redline through the gears might accelerate the failure and therefore I do wind it out but only to 5500 or 6K. This seems good enough to blow out the carbon and smooth out the running of the motor.

Seems to me that my parents gentle treatment has probably contributed to it lasting this long since even with slightly damaged threads there is less stress to contribute more damage. Obviously this is just my gut feeling and who knows if it is even possible to test the theory.

I would say enjoy it and wind it out but not to the degree that you might do with a much younger car. Keep your eye on the gauges and get to know the car so you can watch out for anything abnormal. You will certainly know when there are problems and you are getting good advice as far as maintenance goes.



Howdy.

My folks have a 1995 Eldorado (non-ETC) with less than 40k on the odo. It is the classic retiree special, driven mainly to go to the store or across town to visit the grandkids. Other than a couple of minor cosmetic issues, it looks straight off the showroom floor. It's even painted in Retirement Gold (not sure if that is the official Cadillac color name).

I'm familiar with the head bolt and head gasket issues these cars have. I'm wondering how much more service life he can expect from the engine before it grenades.

Also, what is the general consensus on giving these engines the Italian Tune-up? Since he does mainly around town driving, would it be a good idea for me to borrow the car one day and do the wide open throttle sprint up the on ramp to clear out the carbon?

Thanks!

Ranger
11-10-10, 11:17 PM
I have to wonder if WOT to redline through the gears might accelerate the failure and therefore I do wind it out but only to 5500 or 6K. This seems good enough to blow out the carbon and smooth out the running of the motor.
It's not JUST the high RPM's that keep the engine healthy. It's also the high vacuum created by the 2nd gear deceleration from redline that keeps the rings free and rotating in the lands, thus reducing or preventing oil consumption from stuck rings. The engine was designed and built to be run hard. When it was being tested it was run at WOT for 300 hours (12.5 days) straight.

stngh8r
11-12-10, 10:56 AM
To O.P.

The motors seem to be pretty tough and long lasting aside from the HG issue. As prev. stated, the HG may happen at anytime and it may not. I would change the coolant now and every year or two after. Keep the other fluids changed and enjoy.

A big YES from me on the Italian Tuneup.

Eric