should the LIM in Gm V6's be replaced as PM?

[WhyMe]

i been looking for a GM that will probably have a GM V6. 3.1/3.4/3.8. these are known for bad lower manifold gaskets. i have looked at a couple and can not tell if they have been repleced.

So if i get one, should i wait till it needs it or just replace them as preventive maintainance?

 

[Nick1994]

Replace as preventative maintenance.

 

[901Memphis]

Yes but it's best to just avoid anything with the 3.1/3.4 if possible

 

[BigD1]

3.1 are good engines, and they will run a long time. Parts are plenty and cheap too.

The lower intake gasket was a problem child on GM 3.1 from around 93/94 to round about 2002. GM started using plastic gaskets during those years, but the problem became much worse around 1995/1996 when Dexcool became the off the assembly line coolant. Dexcool and the combination of plastic gaskets were not compatible.

Just check the oil and coolant weekly, and I think it will be fine. But if you can do the job yourself, which is not hard but time consuming, then have it.

 

[Merkava_4]

Skip the 3.1 and the 3.4 and go straight to the 3.8.

My Buick has 122,000+ miles on it and still has the factory original LIM and UIM gaskets.

 

[WANG]

We had like 23X,000 miles from new on one of these (1993 vintage) before the car got really rusty. Replaced the gaskets once, not a big deal. I wouldn't change them if they weren't leaking, though.

I see no reason to avoid the engine family as a whole.

 

[Silverado12]

I agree with what Wang said. I had an Impala with the 3.4 and never had an issue with it. It was a 2004, so they had supposedly worked out the problems by then.

 

[eljefino]

If the price is right go for it. They put out decent power and MPG. It's one of those things where the affected cars are so much ridiculously cheaper it can wind up being worth it.

 

[gulian]

if you look very carefully,if the lim gasket was replaced you should be able to see a little spilage of rtv on the valley of the intake surface contacting the block. if the job's done properly this is usually visible.

 

[MikeHigg]

These GM engines are solid engines, the intake man gasket being the weaipoint. Take what you buy and closely watch the coolant tank and the oil. If anything suspicious appears, change that gasket immediately. All these are 200,000 mile engines (that's what I call them anyway). And here is a key piece of information, if you change the gasket use new bolts and not the old bolts with the 3.1 and 3.4 as they have aluminum heads. Many mechanics won't do this because they don't keep up to date with the TSBs on the engines. Personally, I'd even use new bolts on all three engines. Bolts stretch when they are torqued and to get proper set you must use new bolts. The 3.8 was awarded one of the 10 best engines of the past century by Wards publication, I can't tell you how many of these I've seen with 200K+ miles and still running strong.

 

[WhyMe]

yeah i have watched the how to vids and it does not seem too hard. just time cunsuming. i just dread that it would go bad while i am on a trip. i dread being at the mercy of mechanics

 

[BigD1]

Those lower intake gaskets don't always leak internally. If you are lucky, it will start out as an external leak/weep just like what happened on 1998 Malibu that I bought new. It had two lower intake external leaks. It started weeping externally at 15k under warranty that was fixed, and then again at 90k out of warranty. Put some GM tabs in it, and drove it to 98k before it got totaled.

Like MikeHigg said use new bolts and use blue thread locker too. If you are using an old manual, check with Felpro or who ever because the torque numbers have been revised too.

 

[Bgallagher]

Originally Posted By: 901Memphis
Yes but it's best to just avoid anything with the 3.1/3.4 if possible


As echoed from other people, those engines are nice little powerplants. Decent power and MPG. Besides LIM/HG issue they are otherwise an ultra reliable engine. I have 135k on my Equinox with the 3.4 and couldn't be happier with it's performance.

 

[Colt45ws]

Originally Posted By: Nick1994
Replace as preventative maintenance.

Yes.
And change the coolant.
Or:
Do UOAs regularly
Change the coolant

 

[dishdude]

Originally Posted By: Colt45ws
Originally Posted By: Nick1994
Replace as preventative maintenance.

Yes.
And change the coolant.
Or:
Do UOAs regularly
Change the coolant


No different than if you bought a vehicle equipped with a timing belt. In one weekend and $200 you can put on the problem solver gaskets and never worry about it again - eliminating the only weak point of an otherwise excellent drivetrain.

 

[mike7139]

For the type of engine your looking at the car can't be that expensive. I would just buy it and drive it. I have a 2001 Grand Am GT with the 3400 and that thing started to leak in late 2005 and all I did was put bar's leak in the coolant.