I searched, and got two pages of friggin' n/a to turbo questions (go figure) so bear with me.

How can I tell the difference between an S4 and S5 Turbocharger assembly (minus the manifold). I think I have an S5 from a wreckers. How much shaft play is too much on these Hitachi units?

Thanks, Jason

 

The most obvious difference is the s5's divided housing.

 

both will have somewhat of a divided housing. The best way to tell is that with the S5, both the holes that meet manifold will be the same size, where the S4, one hole will be larger than the other.