GM 3800 lower intake manifold suggestions appreciated

[DoNotLIkeNewCars]

I am installing another lower intake manifold set on my 2002 Buick 3.8 engine (done before at 180K) at 330K. I have several questions:
1. Last time I reused the LIM bolts and have seen other people say I should buy new LIM bolts. Do I need new bolts.? Did you only use blue Locktite on the LIM bolts?
2. Last time I used the two small bars on the ends of the Lower intake manifold. One of the guys I worked with had an auto shop said he did not use the two gaskets on the end of the LIM and used only black RTV. What is your opinion?
3. I changed the upper intake manifold and the pipe in it at 180K and it looks ok today. Should I get an aluminum version?
4. At 180K I did a head redo due to a cracked head. At the time I used the FelPro plastic gasket set. It lasted 150K. Opinions?
Any tips that you used would be helpful. Thanks.

 

[GON]

Most people like the Felpro for the 3800, me included. And like your mechanic, I too used RTV at the ends.

I know you are at 330k miles, but you are the first I can recall needing to replace the LIM gasket on the 3800 post Felpro install.

 

[chemman]

Well, I recently replaced the LIM gaskets on our 99 Buick Century with a 3.1L engine and I'll share with you what a couple of the pros from this forum told me. No real need to purchase new LIM bolts since they are not torqued down that much, Yes, I did use the blue Loctite.

I would go ahead and get the complete Fel-Pro MS98014T gasket set and go ahead and use the two small bars on the ends of the LIM. Use the RTV where the Fel-Pro instructions tell you to use it.

Based on what I have read on this forum and others, purchase the aluminum pipe and replace the plastic one as the plastic one is just waiting to break. Also, if getting a Dorman aluminum elbow, remove the O-rings and replace them with ACDelco O-rings.

Good Luck!

 

[DoNotLIkeNewCars]

Well, I recently replaced the LIM gaskets on our 99 Buick Century with a 3.1L engine and I'll share with you what a couple of the pros from this forum told me. No real need to purchase new LIM bolts since they are not torqued down that much, Yes, I did use the blue Loctite.

I would go ahead and get the complete Fel-Pro MS98014T gasket set and go ahead and use the two small bars on the ends of the LIM. Use the RTV where the Fel-Pro instructions tell you to use it.

Based on what I have read on this forum and others, purchase the aluminum pipe and replace the plastic one as the plastic one is just waiting to break. Also, if getting a Dorman aluminum elbow, remove the O-rings and replace them with ACDelco O-rings.

Good Luck!

At 180K I replaced both plastic elbows with the metal ones. The AC delco o-rings are a good idea. Thanks for the reply.

 

[DoNotLIkeNewCars]

Most people like the Felpro for the 3800, me included. And like your mechanic, I too used RTV at the ends.

I know you are at 330k miles, but you are the first I can recall needing to replace the LIM gasket on the 3800 post Felpro install.

Do you mean you used the two included Felpro bars with RTV on the LIM ends or just RTV without the Bars at each end? Thanks for the reply.

 

[partspro]

My 2 cents, felpro is the only way to go, no contest

 

[frankd]

DoNot wants to use the best gaskets Fel-Pro makes MS98014T Perma dry plus gaskets with the metal frame.

 

[Lubener]

1. you do not need to replace the LIM bolts, just clean them up good before reinstalling.
2. I would only use Fel pro's metal backed gasket or the GM OEM metal gasket set. Follow the directions and use the items in the kit. I used the bars and a dab of black RTV at their ends.
3. Aluminum version is your option. I would use the improved plastic one which you already have.
4. I would use only the metal backed gasket sets from Fel Pro or the OEM set. The plastic OEM LIM gaskets are junk. I used Fel Pro for the LIM and ATP's upper manifold assembly. I prefer that to the Dorman unit.
5. Don't forget to replace the coolant elbows too.

 

[Timmastertech]

The permadry plus felpro gaskets are the best there are for a gm 3.8. I use the intake end seals with dabs of RTV on the ends as the service manual specifies but using RTV is fine as well. I like The Right Stuff for RTV. GM recommends bolt replacement and I replace the bolts when I do them.

 

[zzyzzx]

If I had to do it again, I'd reuse the bolts. That was a waste of money.

 

[tbm3fan]

Hmm, this will be another project of mine. I already have the improved intake, the metal elbows, and Felpro set. The AC Delco O rings was good to know. My father's 2004 Le Sabre only has 54,000 miles but I have always been proactive.

 

[DoNotLIkeNewCars]

Hmm, this will be another project of mine. I already have the improved intake, the metal elbows, and Felpro set. The AC Delco O rings was good to know. My father's 2004 Le Sabre only has 54,000 miles but I have always been proactive.

Wow 54K miles. I bet he took great care of it too.

 

[tbm3fan]

Wow 54K miles. I bet he took great care of it too.

Yes, pristine in and out

 

[Trav]

These are the best I have used for these engines. Felpro copied this design, these are the last design GM came out with in 2008 for the 3800 and have proven most reliable.

Amazon.com: ACDelco GM Original Equipment 89017825 Intake Manifold Gasket Kit with Gaskets and Seals : Automotive

Buy ACDelco GM Original Equipment 89017825 Intake Manifold Gasket Kit with Gaskets and Seals: Intake Manifold - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

www.amazon.com

 

[Ihatetochangeoil]

Yes, pristine in and out
View attachment 58956

This is not "just another Lesabre." It is the Celebration Edition, which came with blacked out grille and side emblems, Buick emblems stitched into the backs of the seats, turn signals built into the heated side mirrors, cherry dashboard trim, HUD, power heated leather seats, custom chrome wheels, a programmable DIC, and everything else the "Limited" started with. I own two of them in my small fleet and would be happy to answer any questions you might have. The classy red color is not so common as my "Bronzemist Metallic." Great cars.

 

[tbm3fan]

On my drive down to Las Vegas, Thanksgiving to visit wife's friends, the Buick threw a "service stability system" message. Haven't put my code reader to it yet since I have only driven it twice since being back but if the sensor in the column, and I hear it is difficult to access, I may ignore.

 

[nthach]

Fel-Pro for the gaskets. For the LIM bolts/studs, I like to use Loctite/Permatex 565 PST. It’s a white, Teflon-loaded anaerobic thread sealant. Use Toyota 103 FIPG(ThreeBond 1207B) or the new GM/Ford “high-performance” RTV, same as ThreeBond 1215H as used by Nissan for the end seals.

 

[Blinker]

the Buick threw a "service stability system" message.

GM vehicles are quick to disable traction control whenever there is a misfire detected. You might discover a misfire code when you hook up your scanner.