before you replace it? In the middle of timing chain replacement on a '94 22RE 4x4. The deepest groove is the depth of the outer band on a penny.. so about 0.7 mm.

(currently reading timing chain & oil pan threads)

 

Main issue is if the chain wears through the cover into the water passages, so if that is not an issue, then it is usually good to use.

 

My opinion....not a very expensive replacement, but a PITA to get at. If you are there, replace it.........the breach in mine was not a gaping hole but was big enough to fail.

 

I went ahead and bought a new one to replace mine but mine was pretty bad. Its a good thing to replace and its safe cheap insurance.

 

Thanks. The deepest grooves are not at the top by the water passages, but near the middle.

 

I reused mine, but installed new chain guides to prevent it from happening anytime soon. The motor will be in the corner of my garage before it kills the new guides.