Broken Crankshaft Count?

Please pick the one that you had break


  • Total voters
    185

Yellow Jacket

WannaBe Sled Puller
Feb 11, 2009
917
0
16
Waterloo, IA
I'm very curious to see this new crank design that your speaking of. I hope they're getting good results.

It is a "new" material, used in funny car, and has full round counterweights. Not designed to mimick or based exactly like a stock crank...

The "metal" has some flex capability and ability to be through hardened instead of surface hardened. Unlike the 4330M that others manufacture and others are selling.
 

islandgirl62

On the road again......
May 22, 2011
34
0
0
Live in a 5th Wheel Full-time!
Crankshaft broke on our 2007.5 LMM. My most recent post on here (I think I only have about 4 posts) was when we were trying to diagnose the problem and it has all the details of the new motor, etc. The crank breaking has everyone scratching their heads trying to figure out what happened and why.
 

durallymax

New member
Apr 26, 2008
2,756
1
0
Under The Hood
Add another one to the list. 09 LMM farm truck. Stock other than deletes and towing tune from Rob. The owner said he was late for something and in a hurry driving it kinda hard and it started running terrible.






 

Slowmax

Build what others' won't
Aug 3, 2013
468
0
0
United States
What is causing these to break, does anyone have any new information they can share? (dampener) Also how can one try to avoid this, alt fire cam, no lock up box, etc...

Thank you
 

coker6303

Keep Calm and Chive On!!
Aug 6, 2009
2,484
0
36
40
Houston, TX
I know the are lots of variables, but what is the most influencing part of the harmonics generated in our rotating assemblies?
 

Harbin_22

Active member
Dec 4, 2010
3,858
7
38
Southern Indiana
Might be adding another the list. Going to pull my engine this week and tear it down I believe.

Went WOT on the race tune from 3rd through 5th, slowed down to 30mph or so to make sure it was out of 4wd and when I started to speed back up, had a terrible vibration. Balancer appears to be wobbling. Balance rates are good, but getiing a cylinder 1&2 misfire. Took converter bolts out to rule it out and the vibration is still there. Balancer key is still good. May get an oil analysis because I can't see any metal in it yet. Might swap some injectors around and do a compression test but I feel like I am pissing in the wind.

Anybody let me borrow a match?
 

sickdiesel

New member
Apr 22, 2010
1,019
0
0
Might be adding another the list. Going to pull my engine this week and tear it down I believe.

Went WOT on the race tune from 3rd through 5th, slowed down to 30mph or so to make sure it was out of 4wd and when I started to speed back up, had a terrible vibration. Balancer appears to be wobbling. Balance rates are good, but getiing a cylinder 1&2 misfire. Took converter bolts out to rule it out and the vibration is still there. Balancer key is still good. May get an oil analysis because I can't see any metal in it yet. Might swap some injectors around and do a compression test but I feel like I am pissing in the wind.

Anybody let me borrow a match?

DUDE! no! sorry to hear man! :(
 

Dirtymaxx03

Active member
Aug 4, 2009
3,109
1
38
Might be adding another the list. Going to pull my engine this week and tear it down I believe.

Went WOT on the race tune from 3rd through 5th, slowed down to 30mph or so to make sure it was out of 4wd and when I started to speed back up, had a terrible vibration. Balancer appears to be wobbling. Balance rates are good, but getiing a cylinder 1&2 misfire. Took converter bolts out to rule it out and the vibration is still there. Balancer key is still good. May get an oil analysis because I can't see any metal in it yet. Might swap some injectors around and do a compression test but I feel like I am pissing in the wind.

Anybody let me borrow a match?

Fuuuuuuuuu sucks to hear man
 

Harbin_22

Active member
Dec 4, 2010
3,858
7
38
Southern Indiana
I haven't thrown in the towel just yet but all signs are pointing that way right now. Brand new LLY crank from GM with around 4,000 miles total on it too.
 

Harbin_22

Active member
Dec 4, 2010
3,858
7
38
Southern Indiana
Just wondering for you guys that have bent/broke a crank. I drove it about 3miles home, ran for maybe 15min in the shop, and I can't see any signs of metal in the oil. I would think it should have been beating the mains out of it with that much run time.
 

Burn Down

Hotrodder
Sep 14, 2008
7,092
28
48
Boise Idaho
Just wondering for you guys that have bent/broke a crank. I drove it about 3miles home, ran for maybe 15min in the shop, and I can't see any signs of metal in the oil. I would think it should have been beating the mains out of it with that much run time.

Did you cut the oil filter open?