Hot take: everyone at my shop swears by the 90 psi torque spec for injector lines, but I think that's too low.

We had a 2019 Freightliner Cascadia with a persistent high-pressure leak that kept coming back after three different guys worked on it. I bumped the torque to 110 psi on a hunch, and the leak stopped for good. Am I crazy, or has anyone else found the book spec to be off on these newer engines?

3 comments

3 Comments

brown.reese25d ago

That 90 psi spec on the '19 Cascadia is a known headache. We had the same leak on a fleet truck, kept blowing out the copper washer. Shop foreman finally said to ignore the book and go to 105. Never came back. Sometimes the manual is just wrong.

the_wyatt15d ago

Manuals are just a suggestion sometimes. Those specs get written for perfect lab conditions, not a truck bouncing down I-80 for half a million miles. Good shop foremen are worth their weight in gold because they know the real world fixes.

grant.finley24d ago

Remember when my buddy's rig had that same drip? He saw @brown.reese's post and bumped his to 110, fixed it right up.