I think my flex plate is loose, I can hear a rattle at idle once it's warmed up. I crawled underneath to see if I could pinpoint it. The rattle seems to be originating right near the access door(as in the posting by jfenley under engine rattle). I called the dealer but they seemed hesitant to give me the torque specs for the 4 bolts on the flex plate, the service mgr said that they could fix it. I would rather do it my self, but i want to do it right. If can help me out with the torque spec that would be much appreciated !

 

80 nm how did you get to the bolts

 

the torque spec i have is 55nm thats in the jag manual

 

Was it the flex plate? I've got a noise thats driving me nuts!! I think it's the flex plate, I've inspected but can only manage to see 2 bolts...??!! Don't know if I'm missing some or I just can't get to them. I found some replacement bolts, Dorman 74070 but can't get them to take in any of the vacant holes on the flex plate.

 

millertic: Flexplates are often called flywheels. They're similar, but not the same. Manual transmissions have flywheels; automatic transmissions have flexplates. Both are inside the transmission bell house and bolt to the crankshaft. They're easily recognized by the large ring gear with teeth that the starter motor grabs to crank the engine.

The key difference is the thickness and stiffness of the metal.
+ Flywheels are thick steel, stiff enough for the manual clutch to push against it and grab when the clutch is released.
+ Flexplates are light, thin steel with large holes so it flexes in the direction of the crankshaft when the torque converter generates lateral force. If the flexplate was stiff and did not flex, it would push hard on the crankshaft and wear out the engine's thrust bearing.

The four bolts holding the flexplate to the torque converter are tightened to 55 Nm / 40 Ft lbs. Rotate the flex plate & crank shaft 90 degrees at a time to tighten all 4 bolts thru the access opening under the transmission, facing the engine oil pan.