[Innovator]

After reading the interchangeability sticky I am left with these conflicting pieces of information. Please confirm the correct information:

1993-1999 and 2000+. You CANNOT under any circumstances bolt a 2000+ engine into a 99 or older body or vice-versa. It simply does not work. Too many differences, too many sensors changed and the holes to mount them. Many people have tried, and gone through all of the work to bolt it in and realize that 1) some things don't bolt up correctly, 2) the wiring won't connect and 3) it won't run.

1993-1999 and 2000+. You CAN bolt a 2000+ POWERTRAIN UNIT into a 99 or older body or vice-versa. A 1998 and 1999 Seville will take a 2000+ unit from a Seville or Deville. You will need to repin connector C101. A 1996 to 1997 Seville, 1996 to 1999 Deville and a 1996 to 1999 Eldo will except a POWERTRAIN UNIT from a 2000+ Eldo. This is 100% functional and it will not have any DTC when done. Some of the other modules may need to be setup to match the VIN or you will need the VIN changed in the PCM to match the car.
POWERTRAIN UNIT: This is the complete unit including the Engine, Transmission, PCM, Harness. You may want to change the Cradle also.
Example: Just wheel the complete POWERTRAIN UNIT out of a 2005 Deville and under a 1998 Seville

 

[rodnok01]

Well that is a bit of Apples and Oranges. First quote is dealing with an engine only(or engine trans combo only)and answer is no there are too many differences.

Second quote is dealing with ENTIRE drivetrain and all associated items(wiring, modules, EVERYTHING) and may very well be true but seems a lot of extra expense and mods for not much in return. Other things I'm sure need changed or adapted/made to work that were not listed.

 

[Innovator]

The first quote is summarized with a few vague conclusions. What doesn't bolt up?

The second is actually the much easier option. Moving a cradle assembly with the powertrain unit from one vehicle to another is significantly less complex than swapping the engines specifically. Is there truly reciprocity with both generations (so to speak)? Fuel, exhaust, steering, throttle and transmission interfaces are all the same?

 

[rodnok01]

Poke around but mounting points, electronics are incompatible, front drive, a bunch of stuff won't line up/physically fit or work period.
Now remember the subframes are probably not the same depending on yr/model also so complete swap may have involved cradles or not. Then steering and suspension would need to be retained. I am willing to bet wiring connection and routing mating old and new will come up also. The reference to We swapped it in and it worked left a mountain of stuff out...
Not saying it can't be done but that year to year swap can eat time. They did the swap because they had a free donor IIRC.
Either way you do it I would not drop another motor in without new rear seal, half case if it even thought it might be leaking, crossover gaskets and of course most would do HG strictly because of convenience.

 

[Submariner409]

AJxtcman was a Cadillac technician with the time, tools, electronics and shop gear to pull off a very, very difficult swap: a 2000+ Northstar powertrain into a pre-2000 vehicle.

JTraik, the differences - mechanical, electrical, electronic, total vehicle - between a 1999 Eldorado and a 2000+ FWD Cadillac anything are so large that to even consider the "swap" is ludicrous. Remember: 1998 - 1999 are VERY different from 2000+.

Repair what you have, if need be.

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Is there truly reciprocity with both generations (so to speak)? Fuel, exhaust, steering, throttle and transmission interfaces are all the same?

NO. None of the systems are the same or compatible. None. If you want to swap the powertrain from a 2000+ into a 1999 you might as well jack up the rearview mirror and run a new car under it.

 

[97EldoCoupe]

When I get some time, I want to work on putting roller cam heads on my 97 Eldorado and then bolting a supercharger on top. There's not enough hood clearance for the Supercharger I have so a cowl hood is a requirement. I need the 2000+ heads on top. It will work, but there will be a ridiculous amount of conversion work needed. Thankfully, most of the parts GM left available across the Northstar year span.

But the #1 issue is you cannot use the newer block/crank/crank sensors with the older PCMs. And as AJXTCman has been stating, that could possibly work.....the whole cradle swap....I just don't see a lot of point or necessity for it. Could it be done? Probably. Is it worth it? I can't see why. If anyone attempts this; my best wishes to them. Where there's a will, there's often a way. Depends on the depth of your pockets and who/what you know.

 

[Innovator]

But the #1 issue is you cannot use the newer block/crank/crank sensors with the older PCMs. And as AJXTCman has been stating, that could possibly work.....the whole cradle swap....I just don't see a lot of point or necessity for it. Could it be done? Probably. Is it worth it? I can't see why. If anyone attempts this; my best wishes to them. Where there's a will, there's often a way. Depends on the depth of your pockets and who/what you know.

So in the case of trying to put a -99 eldo cradle assembly with its original PCM and harness into a 00+ eldo; what are the obstacles?

1. Cradle mounting points?
2. Transmission linkage?
3. Exhaust connection to cat?
4. Steering linkage should be the same.
5. Fuel and throttle seem remedied easy enough.

 

[Submariner409]

Why in the world would you go backwards - delete the advanced roller cam 2000 and later drivetrain for the earlier flat-tappet one ? Again - just about everything is different - from the engine to the mounting to the electricals, to the electronics - everything. I seriously doubt that even the DIC (instrument panel) would function. And that's the tip of the iceberg. Exhaust is different. Fuel and throttle are different. At the very least, in order to even begin, you would need to replace the entire front end and dash wiring harnesses and connectors.

While the Eldorado body/frame was not updated for 2000-2002, it DID get most of the new powertrain - and therefore even the engine/transmission management systems and electronics as well as the wheel/drive systems are very different.

 

[rodnok01]

So in the case of trying to put a -99 eldo cradle assembly with its original PCM and harness into a 00+ eldo; what are the obstacles?

1. Cradle mounting points?
2. Transmission linkage?
3. Exhaust connection to cat?
4. Steering linkage should be the same.
5. Fuel and throttle seem remedied easy enough.

I give up.... When the guy who knows what fits what probably as good as anyone around says can't be done you are OFFICIALLY on your own... When your head gets sore from banging on that wall let us know. It's blatantly obvious you haven't a clue what you're getting into nor do you care to take the experts advice.

 

[97EldoCoupe]

So in the case of trying to put a -99 eldo cradle assembly with its original PCM and harness into a 00+ eldo; what are the obstacles?

1. Cradle mounting points?
2. Transmission linkage?
3. Exhaust connection to cat?
4. Steering linkage should be the same.
5. Fuel and throttle seem remedied easy enough.

I have two Eldorados here. A 2001 and a 1997, both are parts cars. If I were you I'd keep it original. Let me know what you need and I'll see what I can to help you keep it original so everything is plug and play. If you have a LOT of time on your hands and are determined to make a Frankenstein Eldo, I can try to help you achieve those goals- just tell us what exactly your goal is when it's finished (unless I missed reading your goal, I haven't read the whole thread).

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And also; all 5 of the items you mentioned are not an issue, at all. The electronic controls stand in the way. I can tell you the most basic fundamental part; the engine block; is identically the same with the exception of the angle and location on which the crank position sensor holes are drilled. Because someone made a slight change on one of the Makino's at the Livonia engine plant; otherwise identical 1999/2000 engine blocks will not interchange.

Believe it or not; I have the spec sheets on the engines- the actual original; engineered drawings that show the locations and depths of every single hole and machined surface.

 

[Innovator]

And also; all 5 of the items you mentioned are not an issue, at all. The electronic controls stand in the way. I can tell you the most basic fundamental part; the engine block; is identically the same with the exception of the angle and location on which the crank position sensor holes are drilled. Because someone made a slight change on one of the Makino's at the Livonia engine plant; otherwise identical 1999/2000 engine blocks will not interchange.

Believe it or not; I have the spec sheets on the engines- the actual original; engineered drawings that show the locations and depths of every single hole and machined surface.

Thank you very much. This answers my very straightforward questions.

To everyone else, while I value your input, not to be rude but at no point did I ask for your opinions on whether or not such a swap should take place nor your hypotheses derived from such opinions. Technical questions of this sort should be answered in a technical manner, i.e. factually.

 

[MoistCabbage]

It's a forum my friend. You're going to have people giving their opinion along with facts. That's just how it is.

 

[Submariner409]

Because someone made a slight change on one of the Makino's at the Livonia engine plant; otherwise identical 1999/2000 engine blocks will not interchange.

........... and that "slight change" to CKP positioning and mechanical mounting was needed due to the total engine controls and ignition system changes from the 1999 waste spark system to the 2000 coil cassette/individual bank ICM system. That ignition change necessitated a totally different crankshaft and reluctor wheel for the CKP trigger, among other changes.

The statement (question) "Why in the world would you go backwards......" was not opinion. It's fact. The 2000 - 2004 roller cam engines were an upgrade and improvement over the pre-2000 FWD drivetrain - the overall drivetrain changes at the end of the 1999 model year were profound. Sure, you can "bolt up" a 1999 drivetrain into a 2000 chassis or vice versa. Now, get it to run - not just run, but run correctly.

Long threads, but more info on this in several stickies on this forum's main page.