1G Ridge (groove) on Timing belt

[sharkbait689]

I noticed a while ago that theres a ridge on the left side of my timing belt. Its been like this for a while and hasn't hurt anything. Obviously im reluctant to fix it unless absolutely necessary because of how expensive timing belt repairs are. Ive attached a few pictures i took. Can anyone tell how/if this is serious? Thanks for the help

 

[tenn-gsx]

I really cant remember what models. It might be BMW. I know My old Platoon Sgt. was complaining that it cost so much. He went to do it his self and found out there was no drain plug. So he went to the dealer. They use a suction hose down the dipstick tube to get the oil out. One that I do know for sure is RangeRover.

 

[sharkbait689]

"That would suck and your oil change @ express wouldn't be a 15 minute affair, it would be an hour+ Plus you would have to replace the oil pan gasket, downpipe gaskets, etc each time. It would probably double or triple the cost of an oil change. "

Wait, why would it be an hour+? Ive never changed the oil on this car since I dont have ready access to a jack so im not sure what would complicate an oil change.