Header stud torque spec

[DeadEye200321]

Hello!

I couldn’t find a torque spec for the header studs on my 4.0, if anyone knows what the torque spec for those would be, that would be great! See the picture below for the studs I’m talking about, thanks!

 

[CrabGuy]

From the Ranger Forums
For a 2004 Ford Ranger with the 4.0L V6, the exhaust manifold nuts (which secure the manifold to the cylinder head studs) should be torqued to 15 to 16 ft-lbs. The exhaust pipe flange nuts (connecting the manifold to the exhaust/downpipe) should be tightened to 30 ft-lbs

 

[DeadEye200321]

From the Ranger Forums
For a 2004 Ford Ranger with the 4.0L V6, the exhaust manifold nuts (which secure the manifold to the cylinder head studs) should be torqued to 15 to 16 ft-lbs. The exhaust pipe flange nuts (connecting the manifold to the exhaust/downpipe) should be tightened to 30 ft-lbs

That is just the nuts, is there a spec for the studs themselves or is it just snug?

 

[Curious Hound]

No. Fingertight should be fine. When you torque the nuts, you are putting tensile stress on the studs. One torque does it all. That tensile stress is the same as it would be if you were using bolts instead of studs.

 

[CrabGuy]

I would just chase the threads in the head, use hi-temp Locktite, and bottom them out unless it seems abnormally hard to turn. The nuts should be less torque than the studs. If either is over torqued they can break under high heat cycles. Older E30 BMW's had issues with the exhaust studs/nuts being over tightened since the studs were M8 and the copper exhaust nuts were very soft.