My blown head gasket pictures

[WrathOfSocrus]

I can't find the link so I have no proof, it probably was just a listing for something they can make and not an off the shelf product. Definitely pricey but I doubt they had the range of thicknesses to choose from that they have on the store.

[AaronGTR]

I've never had a head gasket problem, but I've never used the fel-pro ones either. Always used GM gaskets, and when I did my head work I used the new GM graphite gaskets and used ARP head studs to get good even clamping force. Still no problems so far. I have set of the MLS gaskets that were made also (the ones with the 3500 bore size) tucked away for a possible future engine rebuild and head change.Wanted to have them ya know just in case.

[gectek]

FWIW i didnt say they were never made, just not made as an off the shelf item. I know they were made. Now they are avail anyday all day

[ssdurango]

So I bought a set of '04 3400 gaskets at the GM dealer. Excepct for the color, they look exactly like the fel-pros, Is there really a difference in their construction, materials ect?

So ROL was bought out by the "feds" eh...Sad...It sounded like they had a better product.

[gectek]

ROL was always federal mogul. and felpro makes nearly all of GMs gaskets. Sometimes they use Victor Reinz but its mostly felpro

[3400-95-Modified]

So I bought a set of '04 3400 gaskets at the GM dealer. Excepct for the color, they look exactly like the fel-pros, Is there really a difference in their construction, materials ect?

I would hope they look the same, otherwise they wouldnt fit... LOL...

The ones I used were all black. That was an 04 3400 set from GM.

Just look on the Engine family tree and such, IIRC it lists on here the upgrades done to each revision/year of the motor, and 04+ has some rear main seal material changes, and same with headgaskets.

Actually here ya go...

http://60degreev6.com/forum/f69/2004-3400-la1-t24990

[AaronGTR]

Interesting read there. Saw a couple things in there I didn't know before. I wonder if there would be any advantage to putting the new cam bearings in an older engine? And they came out with a new lighter flywheel... anyone know the weight difference between them? That could be good for a few HP on an auto equipped car.

[gectek]

flywheels wont work on auto cars....they are flexplates

[AaronGTR]

Yeah I know... they still call it the fly wheel. The article says they made it a common part for 3100 and 3500 engines, and the 3400 never came with a manual so obviously they are talking about the part for the automatic. Most people still call them flywheels.

[gectek]

if it were GM they would call it a plate in the parts system...lol. and idk what much more they could do to a flexplate to make it lighter at all

[1988GTU]

I'd rather have the heavier style. With the newer one and added HP levels on a street car, it would put a small voice in my head telling me that it might crack and come up at me through the firewall.

[AaronGTR]

if it were GM they would call it a plate in the parts system...lol. and idk what much more they could do to a flexplate to make it lighter at all

Hehe, well that is a document directly from GM's powertrain website, so go argue with them about what it's called and about how they made it lighter. I was just quoting what they said.


Since it's connected to the torque converter and I'm sure it's still plenty strong enough I wouldn't worry about it breaking. I highly doubt anyone is going to make enough HP and spin it fast enough to need to worry about that.

[1988GTU]

Grand Nationals have a weak 3.8L with boost and are automatics sitting behind a torque converter..... It's not uncommon to read about those flexplates cracking or oblonged holes.

That is the trade off for automatics not breaking axles like the manual transmission setups.

[3400-95-Modified]

I have the lighter flex plate, I don't think its a significant amount of weight and I've already replaced these "better bearings"... LOL

Stick with what you got... or aftermarket. I'm using replacement sealed power ones... We'll see how they lasted this year.

Flex plate design.
Original Older design


Newer "lightweight" design


What happened to my stock 2005 3400 bearings with a Milzy cam. 15k miles on the aftermarket cam and LS6 springs, and it had 4k on the stock original setup.

[AaronGTR]

Hmm, that sucks about the cam bearings. I hope that isn't whats happening to mine. I have a milzy billet cam with only about 5,000 miles on it but I'm getting higher than normal amounts of aluminum, iron, copper, and molybdenum in my oil tests, and I haven't been able to figure out exactly where it's coming from yet.