Can you reuse the oil pan and front cover gaskets. I have a low mileags LQ-4 that has been apart once, then run for about 20 min. I have to go back in the motor to check my timing chain. Is it safe to use them again?
Also I had a brand new harmonic balancer bolt, and have to pull that off as well. Should I replace it as well?? Thanks

 

Yes, all of the gaskets you mentioned are reusable.

The bolt needs to be replaced.

 

replace the balancer bolt if its just the gm one. its a streach to fit so they get brittal when re-used.

 

The most common NON-reusable stuff on these engines..

-Head & crank pulley bolts
-Head gaskets

Pretty much anything else can be reused as long as it's not worn out or damaged. Use your better judgment when you inspect a seal. Most of them are too damn cheap to risk using again if it looks suspicious of failing.

If you pull your timing cover off, when you put it back on make sure to throw some high temp RTV in the bottom left/right corners where it meets the oil pan. From time to time these spots will leak once the seal is broken, but RTV takes care of it.