8X38mm.

These exhaust manifold studs attach the header pipes to the cylinder head.

Van Cafe recommendation:  If the studs on your motor are in good shape then leave them alone, but if they are stripped, corroded, or broken off then you will need them.

Fits all 1980-1991 Vanagons

There are two studs per manifold, eight per van

Ref ID: N144438