Does the flex plate on a 4.0, auto transmission need to be torqued? If so, anyone have the numbers? Thanks, Murf

 

It should be torqued, but most people just use an impact wrench on it.

 

To the crankshaft or the torque converter?

 

The flexplate to crankshaft fasteners are to be torqued to 105 foot/pounds.

The flexplate to torque converter fasteners are to be torqued to 28 foot/pounds.

 

To the torque converter.

Thanks for the info. I only tightened them by hand and it stopped the noise temporarily. I'll torque them to 28 lbs. Hopefully that ends the noise. Now if I could just stop the voices in my head.

Thanks everyone.

 

Remove them one by one and clean the threads. Apply medium strength LocTite to the threads and reinstall. Repeat. Good luck getting a torque wrench up in there.

 

I use a Craftsman beam type ft/lb torque wrench with a shallow socket to torque these bolts.

Like this:

http://www.craftsman.com/craftsman-3...6&blockType=G6

 

I just finished up replacing mine...2 day...but I am slow... New bolts, cleaned them, medium Lock-tite and torqued per spec.... also new rear motor mount... Jeep is quite and runs great !!!

 

Did ya check it for cracks?

 

Nah. He kept his britches hiked up during the whole procedure.

 

What kind of noise does a potentially problematic flexplate make? I've noticed a kind of rattling noise under the floor lately. Haven't looked closely yet, but on a cursory glance while idling in neutral, thought it seemed to be from the exhaust around the area of the crossover pipe on my '90 Renix 4.0.

 

Sounds like an engine knock.

What you describe is typical of bad trans and engine mounts allowing the exhaust pipe to rattle on the crossmember.

Time for some noggin pokin.

 

Thanks, I've had the engine/xmsn mount rattle on the xmember rattle before, and the mounts are all replaced about three years ago. This sounds different, much lighter intensity....can't even hear it from inside the cab. I noticed it with my noggin poked inside the back where the shell on my Comanche amplifies noises coming through the floor of the bed. Can barely hear it standing outside the truck. Just a new noise on the ol' truck, so thought I'd ask about the flex plate. Probably nothin' really. After 24 years of living with the same truck, one just picks up these little differences.

 

Transfer case mode selector lever bushings