This is my turbine shaft in question (Garrett T3, Stage 3). Took this out and noted an empty groove near the oil seal, is there supposed to be a seal there or is this groove seal-less ?

Also, I developed an oil leak from the turbine side .. does my turbine oil seal need replacing ?
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I want to say when i had mine apart it look like that had an extra groove but I'm not sure hopefully the shodan pops in here.

 

no there is not a seal that goes there just the piston ring style seal.

For it needing a seal i say yes cause you can see where it has been burning oil and getting by the seal

 

Normal to have the groove. Piston sealing ring could use a replacement, and the journal bearing goes infront of that groove on the shaft itself. Make sure it is properly lubed before you install the journal bearing before start up