the 3.9-liter V6 engine verses the 3800 V6

[lasabre]

is the newer 3.9 V6 a better or equal engine to the older 3800V6 what I like is they both do not have a timing Belt. but the water pump location may be a little better on the 3.9 what's your opinion?

 

[2007LucerneCXL]

Regarding the 3.9 there are some versions and other higher selling volumes GM makes that would be worth looking at as to long term reliability.

GM High Value engine - Wikipedia

en.m.wikipedia.org

3.8L S3 as mentioned was the best in the series as GM exclude plastic elbows being held over. So it's reliable without some of the previous version known problems.

As far as replacement of components that would be something to check a service manual on the R&R to see what is involved on that year and engine Lucerne.

 

[lasabre]

GM High Value engine isn't what I would want with overhead camshafts and variable timing.​

how ever if the next 3.8 version is just bored out to 3.9 and everything else the same that would be great and like you said when it comes to belt tensioner replacement its time for Metal elbows.

 

[Buickguy123]

Just from my reading and watching some YouTube videos by mechanics the 3800 series 3 which was only made from like 2004 to 2009 is the best GM engine built in the last 30 years. I have a series 1 in my 1993 Park Avenue and it is still running. 173000 miles. The 3.9 is supposed to be a pretty good engine. The 3.1 has intake manifold gasket leaks however I have one of those too in a 2000 Buick Century with 81000 miles but I removed all the Dexkill coolant right after it was bought and I change it with green coolant every two years. So far no problems. Keeping an eye on it. The GM engine I hear to avoid is the 3.6 V6. Now, some mechanic is going to set my straight which is fine cause I only investigate and read. GM series 3 V6 3800 should be a good pretty good bet.

 

[lasabre]

I'm Just wondering about the 3.9 V6 in the later Buick Lucerne model that took over the Lesabre but looks the same. I ever get another used car I do not want variable valve timing with an overhead cam ,had one on a Nissan pathfinder and was a night mare.

 

[2007LucerneCXL]

The 3.9 was never in the Lesabre as it was discontinued before the engine came out.