So I'm pricing out new engines and the part # for the Intrigue LX5 is 12458123, and the one for the Aurora'* is 12458124, and there is a $700 price difference..what gives? All the cross reference and fitment charts show having the engine interchangeable between models, but that price is telling me otherwise. Anyone know? Some experienced Olds techs out there help out? Don't wanna order the cheaper one to find differences that will cause install or drivability issues

Didn't most auroras come with a 4.0 V-8 and a 4t80e? I don't remember working on one with the V-6. Worked on a ton of intrigues with the OHC V-6

01 and 02 Aurora'* had the Vin Code H 3.5 DOHC V6 available to them, which was advertised as the same 3.5 "H" from the 99-00 Intrigues...just didn't know there was a difference in the two engines or what I should be looking for. All year Aurora'* had the option of a 4.0 V8, but the V6 was very prevalent in 01-02, not available in 03-04 though.

The dealer I worked at wasn't an Olds dealer. We had Buick Pontiac and Cadillac but I worked on a ton of Intrgues because we sold a bunch of them as rental return cars. I do remember a customer who brought in his Aurora because the olds dealer pissed him off and he knew the North Star was basically the same and that we knew how to fix them.

the aurora was a expensive car and the 4.0 engine was kind of the whole point of the car as they were advertising it back then. and racing it. cant imagine getting one with the 6

Guys, not looking for opinions or insight to other cars...Just need some info on the differences between these two engine #'*....anyways, reason behind getting the V6 is longevity and durability over the "little Northstar"

12458123= Federal Emissions
12458124= California Emissions

This will undoubtedly fall on deaf ears, however I hope I can help just one guy out there. These are some of the nicest engines ever designed by any of the OEM'* Asian OR Domestic....Open Deck, Floating Pin, Powdered Metal Rods, Chain Driven Valvetrain,...such a shame GM didn't put this into another make that wasn't in process of shutting its doors at the same time this baby was just getting introduced. No, it'* not a 3.8 that will run for 300,000 miles(most won't anyway), but 250,000 is very possible with maintenance and care to the 3.5L.

Not to me, I'm wondering if the difference is cam profile or compression ratio. Could even be something like a EGR port.

okay, so the differences are all external from what I have gathered. It has A.I.R. system, and this along with the EGR is what makes the CALI emissions package. Timing cover has provisions for AIR system, so does the cylinder head for some reason. Won't know for sure until I pull the engine out of my Aurora.

I was looking to buy another one of these engines and was curious if you ever confirmed that was the only difference when you pulled your engine?