PontiacBonnevilleClub.com

Our Bonne has been an awesome car (after taking care of certain issues) but the miles are really getting beyond my comfort zone (sniff sniff)

We're looking at an '08 Lucerne with the Series III 3.8 and I noticed the UIM (a problem we had with the Bonne) is the aluminum casting. It also had the aluminum-frame LIM gaskets.

Has anyone heard of any issues with these engines, does the aluminum UIM take care of all the issues the plastic ones had (leaking passageways, etc. etc.) I sure hope so! I know they're a darn good engine but I didn't have a very good experience with mine in the Bonne. Read somewhere these have an electronic throttle, but there's no getting away from that in the newer models.

I'm running a Series III in my '97, and it's noticeably different in the way it runs. It's more refined, feels smoother, and it does make a little more power. It's also a bolt-in.

The UIM....there is a way to make it work, but for the normal daily driver, stick with an APN upper kit. The S3 LIM is the same casting as the S2, so you won't need to swap anything over other than the UIM.

Sorry my message was a little confusing as written. I'm not thinking about an engine swap, I'm thinking about a car swap, buying a Lucerne with the Series III (it already has the aluminum UIM of course). I was wondering if anyone knows if they are a true fix to all the problems we had with the plastic UIM on Bonnes. I think it's rated at 197HP.

sandrock wrote:I'm running a Series III in my '97, and it's noticeably different in the way it runs. It's more refined, feels smoother, and it does make a little more power. It's also a bolt-in.

The UIM....there is a way to make it work, but for the normal daily driver, stick with an APN upper kit. The S3 LIM is the same casting as the S2, so you won't need to swap anything over other than the UIM.

Ah. Well, I do have an '06 Grand Prix with the Series III, and I have had ZERO problems with it. Some of them didn't come with the aluminum LIM gaskets (the GP doesn't) so I will have to change those out probably this fall. But so far, the motor is still pretty tight

sandrock wrote:Ah. Well, I do have an '06 Grand Prix with the Series III, and I have had ZERO problems with it. Some of them didn't come with the aluminum LIM gaskets (the GP doesn't) so I will have to change those out probably this fall. But so far, the motor is still pretty tight

Thank goodness the LIM gasket frames are visible externally, it would sure make you wonder otherwise what's on it!

We have a 4.3L blazer w/ 134,000 miles and ZERO engine problems. I've been pretty disappointed with the Series II in the Bonne, but I am hoping the obvious problems have definitely been corrected with Series III.

Keep an eye on the gaskets on the 4.3, also. They also use the nylon LIM gaskets and have been known to cause the same problems.

Archon wrote:Keep an eye on the gaskets on the 4.3, also. They also use the nylon LIM gaskets and have been known to cause the same problems.

REALLY?! There goes my confidence in that engine I was looking and wasn't able to see the gasket edge on that engine. Actually looking at my service records I've replaced an alternator and belt tensioner but that's not really the "engine". We don't use this Blazer much anymore, but maybe a 180 'stat would be a good idea considering those LIM gaskets.

This is a website that details how to replace the gaskets, and shows what can happen to them. It is not a fun engine to work on.
http://www.handymanlyness.com/archives/ ... Jimmy.html

Archon wrote:This is a website that details how to replace the gaskets, and shows what can happen to them. It is not a fun engine to work on.
http://www.handymanlyness.com/archives/ ... Jimmy.html

Thanks Archon. That write-up with photos he did is really something!