My old foreman told me to always use a torque wrench on injector lines, and I finally listened.

He said 'you'll crack a nut or strip a thread if you just go by feel,' and I blew it off for years until I snapped a line on a 6.7 Powerstroke last month. It cost the shop $350 for the new line and my time, which was totally avoidable. How many of you actually torque every single line, or is that overkill on a routine job?

3 comments

3 Comments

derek_burns873mo ago

Honestly, it's the aluminum that gets you. People forget how many newer engines have aluminum heads or intake manifolds. The torque spec for a steel line into aluminum is so much lower than you'd guess by hand. I've seen guys who are careful on an old 12-valve go and ruin a Duramax manifold because they used the same muscle memory. That spec sheet isn't just about the line, it's about the soft material you're threading into.

dylan4133mo ago

Man, you just described my exact learning curve. Rounded off a fitting on my buddy's LS swap because I was used to working on old iron blocks. That click of a torque wrench feels totally different when the threads are in aluminum, it's almost scary how little force it takes. Ruined a whole manifold and had to wait a week for a new one to show up. You really can't trust your gut, you have to trust the spec sheet every single time. What was the worst one you've seen someone mess up?

miller.jason2mo ago

You say you really can't trust your gut, but come on. How many times have you just snugged something up by feel and it was fine? A spec sheet for every single bolt seems like overkill.