I'm looking for a replacement motor for my 2004 LeSabre, and was under the impression that they were all the same from 2000-05. However several of the places I have checked for used engines seem to put the 2000-2004s together and list 2005 separately. Is there actually a difference, or is this a glitch somewhere.

I'm seeing lower milage 2005 3800s for less money, but if they won't work in my '04 the good deal obviously isn't.

Thanks,
Dan

If its the Series 2 L36 N/A engine, they are the same from 1995-2005. 2005ish, they came out with the Series 3.

I read somewhere that the block, rods, and heads for 2005+ Series 2 were actually Series 3 units while the intake and electronics remained Series 2 . Can't remember where I saw that though. If true, that would explain it.

Odd that they are listed like that, according to the vehicles history."""The standard, and only available, engine for the eighth-generation LeSabre was the 3.8 L Series II Buick 3800 V6 providing:

• Power: 205 hp (153 kW)
• Torque: 230 lb·ft (312 N·m)"""

One thing I noticed was this..

"""The LeSabre was America'* best-selling full- size car when it was discontinued at the end of the 2005 model year. It was replaced in 2006 by the Lucerne, Buick'* newly designed flagship. The last LeSabre rolled off the Lake Orion, Michigan assembly line on June 18, 2004 (retooling the plant to build the Pontiac G6) and the last Hamtramck, Michigan LeSabre rolled off the assembly line in mid-August, 2005."""

Maybe that has something to do with it, shrugs..

Thanks.

From further research it looks like the places that sell rebuilt engines & places that sell parts don't see any difference between 2000-05, while the junkyard sites & used engine sites separate the '05 engines. So I'm assuming it is either a mistake in some junkyard database, or some incredibly small difference that changed a part number but doesn't really matter. Hopefully.

There may be some production cars out there with the Series 3. You can always tell just by the intake, Series 2 have the black plastic plenum. Series 3 have the aluminum plenums.

If it helps any, I believe the series 3 block is interchangeable with series 2, it'* just a question of what all needs to be swapped over (UIM/LIM, oil pan, etc). I believe there has been several mentions of it through the years. A targeted search would likely be beneficial. There was a point that series 3 engines were easier to come by due to the increasing age of series 2

Not only the block is the same, but from what I've read, the last year or so of S2 engines had the same internal upgrades as the S3.

Anyway, my '05 S2 engine arrived, and from at least a casual look I don't see any differences so far. Going to move the car, and start work this week.

Let us know how it goes please. And good luck, hope all goes together well!

11 hours over 6 days and the old engine is out without breaking anything. So far, so good.