Rear diff cover question

[f350peter]

Hey all,

Tomorrow I'm going to change my rear diff fluid and I'll be replacing the diff cover at the same time. I got one of those finned aluminum covers from fordparts.com and I finally have a chance to install it.
My question is, do I need to use lock washers? I'm changing the bolts to 5/16-18 X 1 1/2" socket heads with flatwashers, and I'll be torquing them to factory specs (33 - 36 ft-lbs I think). Are lock washers necessary?

Thanks!
Peter

[bigcountrysg]

what is the purpose for changing the bolts.

[TwinTurboStroker]

Originally Posted by bigcountrysg

what is the purpose for changing the bolts.

For looks I'm sure, because those would look way better than the nasty black bolts from the factory...... I don't see a need to use the lock washers if the torque specs are only 34lbs, but thats just my