Flex plate

[Spindrift]

Has anyone lost a flex plate? One minute I start the truck and it runs fine. About an hour later I go out to the truck to run an errand, start the truck and all of a sudden I hear a racket that makes my heart stop. Definitely sounds rotational and as near as I can tell it's coming from the bottom end at the rear of the engine. Sounds like a rod knock. Checked oil pressure at idle and I'm at 50psi...rev the engine a little and pressure jumps to 75psi. So I really doubt I've lost a bearing or I'd see a drop in oil pressure from normal. I'm thinking/hoping I have a transmission issue.

Truck has 118K on it. Nothing has been done to the trans.

 

[NEVRNF]

same thing happened to my E99. They break the flex plate under the big round washer that the bolts go through. If you drop the trans it wont look like anything is wrong until you take the bolts out of the crank then the flywheel will fall in 2 pieces

 

[Spindrift]

Were you able to make that diagnosis before dropping the trans?

 

[Rideracelivemx7]

flex plates make the worst noise when gone. my buddy pulled his dmax motor out for a knock at 220k, got the heads off and checked the motor out. everything was fine, should have dropped the flex plate first, thing was effed LOL