That looks to be the right nut. Thanks Alec300SD.
I wonder if non-turbo engines have smaller diameter manifold studs.

I tried my old nuts as tangofox007 suggested. I could only get them thread on up to the crown of the nut (the ovaled part) so it looks like the self-locking feature is still intact.

Thanks All

__________________
JIM


83 300TD
2006 Sprinter 2500 (RV Conversion)

06 E320 CDI, Sold

83 240D, manual, Sold
79 240D, automatic, Sold