I may have the opportunity to purchase a 2005 Impala with 3400 engine. How durable are these engines? Are they plagued by the intake gasket failures of previous models? Need to know quick, may make the purchase Friday morning. Thanks for your help!
GM 3400 engine
- Thread starter otis24
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Other than the gasket issues that are so common in this and other GM engines, it is a decent engine. We had a 2002 Impala with this engine but got rid of it after the gasket issue at about $40k (just out of warranty), and the tranny started worrying me around 50k (might have just needed a fluid change, but I wasn't taking chances). The factory rotors are really bad on those Impalas as well. We traded it in after less than a year and a half for a Vibe we've had since.
All in all, though, I'd buy one used again if I could get a good deal and knew it had a good history with aftermarket rotors, timely tranny flushes, and the gasket fixed with the update.
All in all, though, I'd buy one used again if I could get a good deal and knew it had a good history with aftermarket rotors, timely tranny flushes, and the gasket fixed with the update.
Does this generation of 3400 engine have a timing chain? Are timing belts used at all in this engine?
Timing belts are not used in this engine. Intake gaskets are still a concern, but beyond that, this engine is a good one. Decent power and mileage and they'll go 200k plus to boot. My wife's 3.1 (little brother to the 3.4) has 243k and still ticking.
If I were you- don't let the intake gasket issue scare you away. It's a solid engine otherwise. Buy the car and have the gaskets swapped for the Fel-Pro metal backed gaskets and call it a day. It'll be the last major thing you'll have to do to it.
If I were you- don't let the intake gasket issue scare you away. It's a solid engine otherwise. Buy the car and have the gaskets swapped for the Fel-Pro metal backed gaskets and call it a day. It'll be the last major thing you'll have to do to it.
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No timing belt. Small overhead valve engine chain. I don't think I've ever seen a 2.8, 3.1, or 3.4 60 degree GM need a timing chain. Not unless they needed a lot more than that.
Not every single 3.4 had intake manifold gasket problems. But some did. It's something to monitor but I wouldn't necessarily condemn the cars for that reason.
The name is unfortunate. Impalas are RWD and built on a frame. We call it the Lumina II or the Chevrolet Imposter.
But they are not bad cars.
The powerband on it is pretty good. On paper, the competition's 24 valve DOHC 3.0s, 3.2s, and 3.5s blow it away, but it never feels "slow". Decent passing power. Not overwhelming but it feels better when you mash down on the skinny pedal on the right than the numbers suggest.
Not every single 3.4 had intake manifold gasket problems. But some did. It's something to monitor but I wouldn't necessarily condemn the cars for that reason.
The name is unfortunate. Impalas are RWD and built on a frame. We call it the Lumina II or the Chevrolet Imposter.
The powerband on it is pretty good. On paper, the competition's 24 valve DOHC 3.0s, 3.2s, and 3.5s blow it away, but it never feels "slow". Decent passing power. Not overwhelming but it feels better when you mash down on the skinny pedal on the right than the numbers suggest.
I'm looking for a car that will make it to 200k. With my current job, I'll be travelling 40k per year.
If I recall correctly, GM had the intake gasket issue under control before the 2005 model year.
Originally Posted By: otis24
I'm looking for a car that will make it to 200k. With my current job, I'll be travelling 40k per year.
Then it, or a Buick LeSabre/Park Avenue is your car.
Originally Posted By: otis24
I'm looking for a car that will make it to 200k. With my current job, I'll be travelling 40k per year.
Then it, or a Buick LeSabre/Park Avenue is your car.
Had a 2004 LeSaber Limited, one owner with 39k miles. I was going to buy it on Friday but a customer came in and I was forced to sell it to him.
Outdated OHV technology(hat-tip to LS series that are an exception). Unless you're a GM guy looking for a commuter, or are getting a sweetheart deal on it I'd look elsewhere IMO.
Outdated tech yes, expired not at all. Finding a 38k miles example I'd be all over regardless.
ls1mike
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By 05 the intake gasket was fixed. It should also have the updated intake, bottom end as heads as well as it was updated to share parts with the 3.5.
Outdated? Because Mercedes wasn't using OHC back in the 1920's. Heavy Sarcasm. It was even invented before then.
What makes it out of date?
Just because something dosen't use OHC dosen't mean it is outdated. It has all of the modern electronics that any engine from the time frame was using. Instead of using one long belt/chain or extra cams. You have one and nice tight timing chain that will be very reliable and simple to maintain.
Outdated? Because Mercedes wasn't using OHC back in the 1920's. Heavy Sarcasm. It was even invented before then.
What makes it out of date?
Just because something dosen't use OHC dosen't mean it is outdated. It has all of the modern electronics that any engine from the time frame was using. Instead of using one long belt/chain or extra cams. You have one and nice tight timing chain that will be very reliable and simple to maintain.
Originally Posted By: meangreen01
Outdated OHV technology(hat-tip to LS series that are an exception). Unless you're a GM guy looking for a commuter, or are getting a sweetheart deal on it I'd look elsewhere IMO.
I'm always very curious where people come up with this stuff. Marketing must really get into peoples heads if they think there's some overwhelming reason to go with an OHC engine over an OHV for 99% of drivers. I can't figure out whether it's the vastly simpler mechanics, lower weight, or higher long term reliability that turns people off. Unless you're trying to spin the engine to 7k rpm or something I fail to see the huge disadvantage to OHV design.
Outdated OHV technology(hat-tip to LS series that are an exception). Unless you're a GM guy looking for a commuter, or are getting a sweetheart deal on it I'd look elsewhere IMO.
I'm always very curious where people come up with this stuff. Marketing must really get into peoples heads if they think there's some overwhelming reason to go with an OHC engine over an OHV for 99% of drivers. I can't figure out whether it's the vastly simpler mechanics, lower weight, or higher long term reliability that turns people off. Unless you're trying to spin the engine to 7k rpm or something I fail to see the huge disadvantage to OHV design.
I've got a 2003 Impala with about 77,000 miles, and so far the only major problem was I did have to replace the front rotors. Keeping an eye on possible intake manifold problems. Very smooth and comfortable on the highway, and we have seen 32 mpg on long highway trips at a steady 65 or so. Range on a full tank of gas is well over 400 miles on the highway, which is nice on trips too. Huge trunk, comfortable back seat, decent handling, a bit low to the road for deep snow driving but decent traction with front drive, realtively easy to do oil and filter changes, pain in the you know waht to change the air filter, get rid of the Dexcool ASAP and use something else.
I had this in a silhouette van and it scooted. In a lighter car it should be a great motor.
Piston slap when cold sounds angry.
Replaced my 26 MPG highway silhouette 3.4 with a 27.5 MPG century 3.1 sedan-- the 3.4 gave a lot more output for its fuel input!
Piston slap when cold sounds angry.
Replaced my 26 MPG highway silhouette 3.4 with a 27.5 MPG century 3.1 sedan-- the 3.4 gave a lot more output for its fuel input!
Originally Posted By: cchase
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I'm always very curious where people come up with this stuff. Marketing must really get into peoples heads if they think there's some overwhelming reason to go with an OHC engine over an OHV for 99% of drivers. I can't figure out whether it's the vastly simpler mechanics, lower weight, or higher long term reliability that turns people off. Unless you're trying to spin the engine to 7k rpm or something I fail to see the huge disadvantage to OHV design.
That's why I said, "on-paper" when referring to advantages.
The Ford Taurus' Duratec 3.0 makes 20 more horsepower out of 400cc less displacement. But if you drive them back to back, I doubt you'd really notice those extra 20 hp in the Taurus. In fact, given the Imposter/Lumina II's torque advantage, many drivers would believe the Chevy to be quicker in acceleration...and it may well be.
....
I'm always very curious where people come up with this stuff. Marketing must really get into peoples heads if they think there's some overwhelming reason to go with an OHC engine over an OHV for 99% of drivers. I can't figure out whether it's the vastly simpler mechanics, lower weight, or higher long term reliability that turns people off. Unless you're trying to spin the engine to 7k rpm or something I fail to see the huge disadvantage to OHV design.
That's why I said, "on-paper" when referring to advantages.
The Ford Taurus' Duratec 3.0 makes 20 more horsepower out of 400cc less displacement. But if you drive them back to back, I doubt you'd really notice those extra 20 hp in the Taurus. In fact, given the Imposter/Lumina II's torque advantage, many drivers would believe the Chevy to be quicker in acceleration...and it may well be.
Originally Posted By: eljefino
I had this in a silhouette van and it scooted. In a lighter car it should be a great motor.
Piston slap when cold sounds angry.
Replaced my 26 MPG highway silhouette 3.4 with a 27.5 MPG century 3.1 sedan-- the 3.4 gave a lot more output for its fuel input!
I got one in a 98 Montana that has 163,000 on it. Have replace intake manifold gasket 3 times (finally last time with the Fel-Pro problem solver) and a head gasket job.
I get 24-27mpg on a long trip depending on conditions. There isn't a new van that will get that kind of mileage that I can find.
I had this in a silhouette van and it scooted. In a lighter car it should be a great motor.
Piston slap when cold sounds angry.
Replaced my 26 MPG highway silhouette 3.4 with a 27.5 MPG century 3.1 sedan-- the 3.4 gave a lot more output for its fuel input!
I got one in a 98 Montana that has 163,000 on it. Have replace intake manifold gasket 3 times (finally last time with the Fel-Pro problem solver) and a head gasket job.
I get 24-27mpg on a long trip depending on conditions. There isn't a new van that will get that kind of mileage that I can find.
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Originally Posted By: Spazdog
That's why I said, "on-paper" when referring to advantages.
The Ford Taurus' Duratec 3.0 makes 20 more horsepower out of 400cc less displacement. But if you drive them back to back, I doubt you'd really notice those extra 20 hp in the Taurus.
I bet you'd notice the difference at the pump. I'd be surprised of the Taurus could come within 5 MPG of the Impala.
That's why I said, "on-paper" when referring to advantages.
The Ford Taurus' Duratec 3.0 makes 20 more horsepower out of 400cc less displacement. But if you drive them back to back, I doubt you'd really notice those extra 20 hp in the Taurus.
I bet you'd notice the difference at the pump. I'd be surprised of the Taurus could come within 5 MPG of the Impala.
Originally Posted By: meangreen01
Outdated OHV technology(hat-tip to LS series that are an exception). Unless you're a GM guy looking for a commuter, or are getting a sweetheart deal on it I'd look elsewhere IMO.
+1. After working at a GM dealership service dept. I've seen enough to never own a product made by the "general" EVER again.
Outdated OHV technology(hat-tip to LS series that are an exception). Unless you're a GM guy looking for a commuter, or are getting a sweetheart deal on it I'd look elsewhere IMO.
+1. After working at a GM dealership service dept. I've seen enough to never own a product made by the "general" EVER again.
Had 2 major engine breakdowns in the family in the last few years---a 3400 that blew a head gasket and overheated(we had engine replaced) and a 3100 that a leaking intake manifold gasket caused a cylinder to hydrolock, killing a rod bearing(car went to graveyard).
I'm another member of the "Never own another GM" Club.
I'm another member of the "Never own another GM" Club.
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