Current generation GM V6's

ebc

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Hello, I have owned a 2.8L V6 Grand Prix and a 3.1 L model as well. Both sprung oil leaks around the intake/head area requiring a costly fix. Has GM addressed this issue in the 3.5 to 3.8 liter engines in the current FWD cars like the GP/Monte Carlo/Impala? The cars were pretty sold save for that problem. Thanks, BC
 
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That sounds like your o-rings dried up on the plugs that went "where the distributor used to be". on the 60-degree (small) v6s. I think they fixed that, but they're having huge problems with the intake manifolds leaking coolant into the cylinders now... and piston slap when cold is something else to look out for. The 3.8 is a 90 degree design that's totally different, slightly better, but could still have that coolant problem.
 
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2003 and newer cars shouldn't have the coolant leak at the intake manifold. The oil leak hasn't been a problem for quite some time to my knowledge.
 
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I've read that there's a new fix for the intake manifold leaking coolant. it maybe awhile until we know for sure it's the real fix or not. I'll be watching the UOA section for sure b/c I've got GM card earnings I want to use up in the next six months. 6.5 years of earnings on the card.
 
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The oil leak hasn't been an issue in several years (I think since 95) but the concensus is still out on the manifold gasket leak. Remember, GM kept coming out saying "we fixed it, we fixed it even though it wasn't a problem and it's all in your head, we swear it's fixed this time". They said the 99 engines were problem free. WRONG. Then the 2001 engines were fixed. WRONG. Now the 03's ? We'll see. And the piston slap is still there, although it doesn't sound as bad as the older engines did.
 
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A bad design is a bad design. I wish GM would relegate it's 3.4/3.5L OHV designs to the library of "things not to do" rather than continue to produce them. What ever happened to the DOHC V6 that was in GM's upscale models?
 

ebc

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Good thread, Actually, I was thinking of the 3.8l supercharged V6 in the Grand Prix. Any stories on that engine? Thanks again, ebc
 
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quote:
Originally posted by ebc: Good thread, Actually, I was thinking of the 3.8l supercharged V6 in the Grand Prix. Any stories on that engine? Thanks again, ebc
That engine is a totally different animal than the 60 degree family (2.8/3.1/3.4/3.5/3.9L). The 3.8L (231 CID) is a 90 degree design that traces its evolution back to a 198 CID iron block V-6 that started production in 1961. That engine, supremely ironically, traces its roots to an experimental aluminum V-8 that Buick was working with in the late 50s. This engine may be an oldster, but it's a good one. By and large, it has had none of the repetitive problems that the 60-degree family has suffered over the years. Other than the slight roughness that's a result of the fact that its a V-6 and has pushrods, it's a fantastic engine, and IMO, one of GM's best all-time designs. I owned a car with the supercharged version and it was great. Not as beautifully smooth as my present Infiniti DOHC V-6, but its low end torque launched my car as if it were hooked to an aircraft carrier catapult. If a friend were considering a car with this engine, I'd recommend it with enthusiasm. [Cheers!]
 
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quote:
Originally posted by ToyotaNSaturn: A bad design is a bad design. I wish GM would relegate it's 3.4/3.5L OHV designs to the library of "things not to do" rather than continue to produce them. What ever happened to the DOHC V6 that was in GM's upscale models?
The GM DOHC is alive and well. Off the top of my head, it is being installed in a couple Buick models (top-of-the-line La Crosses and Rendesvous models). It may be in some others I'm not aware of too. I don't know that all is lost with the 60-degree V-6s. It has taken GM a shamefully long time, but it looks like they've finally got them into at least acceptable shape. They're even being done with variable valve timing too. Interestingly, the latest version of this persistent design is designated as a 3.9L. If you look at its actual displacement specs, though, you'll see that it's actually a 3.8L (it's exactly 3791 cc, or ... ooops ... 231 cu-in, per Chevrolet.com). I suppose they just arbitrarily called it a 3.9L to differentiate it from the real 3.8L V-6. [Roll Eyes]
 
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quote:
Originally posted by ekpolk:
quote:
Originally posted by ebc: Good thread, Actually, I was thinking of the 3.8l supercharged V6 in the Grand Prix. Any stories on that engine? Thanks again, ebc
That engine, supremely ironically, traces its roots to an experimental aluminum V-8 that Buick was working with in the late 50s.

To add to the twist, that aluminum V8 was sold to Rover of England and appeared in many British vehicles.
 
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Google is your friend: http://64.233.187.104/search?q=cache:Nucv-psYIboJ:www.findarticles.com/p/articles/mi_m3012/is_9_181/ai_79007382+gm+isuzu+honda+engines&hl=en "No two companies are rolling the dice more than General Motors Corp. and Honda Two years ago, they broke the rule about never buying an engine from a direct competitor. In a provocative engine-sharing agreement Honda will provide Saturn with a ULEV V-6 for the new Saturn Vue. In return, GM ally Isuzu will give Honda a 1.7L turbo diesel for its 2002 Civic program in Europe. Production for the Civic begins in November, with approximately 5,000 engines to be provided during the next six months."
 
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quote:
Originally posted by jtantare: Why is GM buying V6 engines and trasmissions from Honda?
GM swapped some diesels (either Fiat or Isuzu, I don't remember) w/ Honda for the 3.5l v6
 
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Recently, I got the chance to sit behind two rental cars: Pontiac Bonnieville with the standard 3.8L and a Buick LeSabre sister car with the same 3.8L V6. The Pontiac seemed to have more spirited throttle response while the Buick felt like my "father's Olds". I was impressed that for a big V-6, 23-24MPG was achievable even while stomping on the throttle alot. I'm sure if I kept it *below* 80MPH and the A/C off, 32-34MPG would be a realistic goal. GM did the 3.8L right.
 
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Let's not forget the 3800's had its share of problems, too; it suffered from leaky manifold gaskets, and what was worse was that both the upper AND lower sets were prone to failure. The EGR pipe was situated to closely to all that heavy duty plastic, causing melting. The 3.8, like the 3.1 clones, are still good workhorse motors, I prefer them over the other V6 GM's cause of their power and relative quiet. I also think the best factory supercharged engine in recent years was the 3.8, especially the ones in the Park Avenues.
 
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The 3.4L's in my 4 Montanas seem to be doing OK. So far I've only had to do 1 intake gasket on an 01 at 100k miles. It cost around $600 to replace. It's currently at 260k and runs great. A little valvetrain noise once in a while but nothing to be concerned about. I have an 03 with 150k and no signs of a coolant leak yet. Hopefully the rumors of the problem being fixed in 03 are true. Performance wise I'm happy too. MPG is great, operation is smooth and quiet and it has more than enough grunt for getting around town and passing on the hiway. Oil consumption has always been very low with various Xw30 oils.
 
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quote:
Originally posted by simple_gifts:
quote:
Originally posted by ekpolk:
quote:
Originally posted by ebc: Good thread, Actually, I was thinking of the 3.8l supercharged V6 in the Grand Prix. Any stories on that engine? Thanks again, ebc
That engine, supremely ironically, traces its roots to an experimental aluminum V-8 that Buick was working with in the late 50s.

To add to the twist, that aluminum V8 was sold to Rover of England and appeared in many British vehicles.

These posts imply that Buick never actually produced this engine. Buick Skylarks and Oldsmobile F-85's between 1961 and 1963 had them. The Olds version was even offered turbocharged. The cast iron V-6 was introduced in the 1964 model year when those cars became much bigger and heavier "midsize" replacing the original "compact" models. My uncle and grandmother both had aluminum V-8 Skylarks.
 
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