Cadillac Deville 95 or 96?

I have been looking at a couple of Cadillac Devilles. I came across two that appear to be in very good shape: a -95 and a -96. I can't find any major problems with them but I am not sure which one I should buy.

Which engine is best/most reliable (in general)? The 4.9l V8 in the -95 or the 4.6l Northstar in the -96?

Also, there is a "security" dashboard light that was on constantly on the -95. What is this light for? The owner said it has always been on.

Any other goods/bads for any of these two models?

Reply to
Kristofer Andersson
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I'd go for the 96.

Reply to
Paradox

Any specific reason? Because it is newer or is the Northstar engine better than the 4.9l?

Also, the owner claimed that the 4.9l engine has variable displacement. After searching the web I could only find info about variable displacement on 1981 models. Does this engine really have variable displacement or is he misinformed?

Reply to
Kristofer Andersson

"Kristofer Andersson"wrote

Both.

He's misinformed. Cadillac only had variable displacement for 1 or at the most 2 years in the 80's. The Northstar is a great engine, very robust, lot's of power. It has it's problems, and is quite expensive when you have to do any repairs. Before you buy it, you should have it checked at a Caddy dealership (they will know what to look for) and look specifically for oil leaks from the lower case halves, oil present in the valley between the cylinder banks, and coolant leaks from the water pump and/or head gaskets. Any sign of any of these problems means you will have to spend some big money in repairs.

I think that next years truck engines will have variable displacement.

Ian

Reply to
shiden_Kai

Ok, thanks.

There was oil between the cylinder banks on the 95 (4.9l) and some oil on the bottom pan of the engine. No visible leaks, but oil was present. I will go for the 96.

Reply to
Kristofer Andersson

We have a 94 Deville with 135,000 miles on it with the 4.9L. So far a great engine with nary a problem other than normal oil changes, etc.....

That would be the security system warning. It is supposed to flash upon entry/exit (e.g. when doors open) and if the security system engages...

Wir welle bleiwe wat mir sin (Letzebuergesch)

Reply to
munir

which also honks the horn and blinks the lights for 3-5 minutes (seems to vary some in the tests and inadvertant triggers of the system we've done)

If you have the 4 button key fob, click the lights or lock door button, should deactivate it

Wir welle bleiwe wat mir sin (Letzebuergesch)

Reply to
munir

96 has ODB-II diagnostics. You can scan it before you buy it if you want (with a scan tool). When you have trouble, diagnosis should be easier. A 95 may or may not be OBD-II.

OBD-II isn't magic for finding problems, but it's better than not having it.

Reply to
David

Here's a dissenting opinion on the Northstar.

My Dad drives a '94 Deville with the 4.9L. It has sufficient power, sufficient smoothness, has been 100% reliable and gets fantastic gas mileage... 30+ mpg in relaxed highway driving... amazing for such a big, heavy vehicle.

Northstar will have more power and will be more responsive, but expect it to chew through more fuel and I've heard a few stories about reliability problems (more around accessories bolted on to the Northstar than the core "stove") from owners in my geography...

Best of luck with your choice, Mike

Reply to
Mike

Our experience echos this, we routinely get 18.5+ mpg around town and upwards of 27-30 on the highway when cruising at 70 mph...

The engine is great, it's the overengineered systems on the car that will start to nickel and dime you when the car gets on in age. Especially electronics...

Wir welle bleiwe wat mir sin (Letzebuergesch)

Reply to
munir

How closely related to the old 4.1 is the 4.9? If its anywhere close AT ALL, I'd be tempted to avoid it (former 4.1 maintainer speaking... thank heavens its long gone).

When the 4.9 was the flagship engine (right up to the debut of the Northstar) I wasn't really hearing many complaints about the 4.9, though. And it seems much simpler and more straightforward than the Northstar, so I wondered why you considered the Northstar "better" all around.

Reply to
Steve

"Steve" wrote

Pretty much the same engine, just a different displacement. But...I will give Cadillac their due....the 4.9 seems to have ironed out many of the problems with that line of engine. I still don't like them...why on earth would Cadillac make an engine with an aluminum block and cast iron heads? There must be a good reason, but I don't know what it is.

It's all aluminum, it's beautifully made, and it's very rugged. There are some weak spots...the case half seal was a problem, it's not as as bad on the later models, the fact that they didn't install steel thread inserts into the block (for the cylinder head bolts) is a mystery to me....we often have to remove the heads on these engines, drill, tap, and helicoil (though they are called timeserts, superior product to a helicoil) in order to keep the head gaskets from leaking. The engine is designed so that coolant "cannot" mingle with the engine oil from such things as intake manifold leaks..etc. I've had numerous Northstars apart at high mileage....main bearings always look almost brand new. The cylinder walls "never" exhibit any signs of wear....even at over

100,000 miles.

I'd run one...happily.

Ian

Reply to
shiden_Kai

strange it is as it's usually the reverse on engines, cast block and alum heads.

They like to over engineer things. Layoffs would insue if they didn't LOL

Wir welle bleiwe wat mir sin (Letzebuergesch)

Reply to
munir

Do you know if there are known problems with '90 4.5 engine?

Hav>

Reply to
Here&There

That's what I thought. The 4.1 was an engine that was very good on paper and had surprisingly good power numbers for its size, but was just an all-around PITA to work on and had a lot of things that made it horribly unreliable (mostly NOT hard parts in my experience, but ancillary things like using the EGR system as a mandatory part of the computer's knock-suppression algorithms.) I guess I should really say that it was "very intolerant of owners not fixing problems IMMEDIATELY."

I can only guess that using iron heads was either a matter of economics or dictated by some weakness in the head structure that required the added strength of iron. The only other "iron-over-aluminum" engine I can think of was the very early (60-62) Chrysler slant-six which had an aluminum block under an iron head. GREAT engine, but much more costly to produce and was replaced by the all iron version after a couple of years. If Dan Stern reads this, he can probably tell us exactly why the head was always iron on that engine.

so I wondered why you considered the Northstar "better" all

Those are about the reasons I would have guessed. I'm pleased to see that it has proven "rugged" in the real world, since I had real doubts about it when I first looked through the information on it back in '92 or '93. I think a lot of its ruggedness probably stems from the fact that its engine management system is so vastly superior to the earlier ones. A 4.1's engine computer would destroy the engine through detonation if the EGR servo failed because it wouldn't retard the timing enough, and things like that just don't happen on newer computer-controlled engines. I don't see cylinder wall wear on 60s vintage engines that were rebuilt and run 200k miles since the mid 80s, provided good oil is used, so I credit modern oils with that as much as anything else.

Reply to
Steve

"Sounding like a diesel when cold" is most likely piston slap, caused by either collapsed piston skirts or just too much piston-to-cylinder clearance. What prompted the bearing replacement? Was it ever run with a lot of detonation (knocking) going on? That can collapse skirts *and* pound main and rod bearings. And it sounds like you might still have a detonation issue at light throttle...

Reply to
Steve

There was rattling noise that got noisier as engine got warmed up. The rattling disappeared after the bearing. But the diesel-engine sound at cold start was not that noisy before the bearing replacement

- it was always noisy, but not that noisy. Noticed the detonation issue around the time of bearing problem, not before.

Is there a way to determine the "piston" problem, and better yet, is there a quick fix, like using synthetic oil or snake oil?

Reply to
Here&There

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