c/diesel-mechanics

My apprentice asked why we always pressure test the fuel system before a major injector job, and his simple question made me realize I'd been skipping a step on my personal truck for months.

He pointed at the service manual for a 6.7 Powerstroke and said, 'It says right here, a 5 psi air check can find a cracked cup before you waste a whole set of injectors,' which hit different because I'd just replaced two on my own rig without checking first.

A guy at the truck stop near Toledo told me I was wasting my time with a manual gauge

I was checking fuel pressure on a 6.7 Powerstroke in the lot, using my old reliable mechanical gauge. This older mechanic walked over, saw what I was doing, and said, 'You're still using that thing? The scan tool data is good enough, you're just making extra work.' I told him I've seen the sensor data lie before, and the needle doesn't. He just shook his head and walked off. Has anyone else had a shop try to phase out physical gauges completely?

Shoutout to the old timers who taught me to use a pry bar on every injector, but I switched to a slide hammer after a 6.7 Powerstroke in Spokane fought me for three hours.

I used to think a pry bar and some persuasion was the only way to get a stuck injector out, but that changed last spring when I spent half a day on a job and finally borrowed a neighbor's OTC slide hammer puller, which popped it out in two minutes flat... so when did you guys stop fighting with pry bars?

Read in a shop manual from 1998 that a 7.3 Powerstroke can have up to 17 quarts of oil in the whole system, not just the pan... always thought it was just the 15 the book says to put in.

PSA: That 'easy' DEF line flush on a Cascadia can turn into a full day job

Last week at the shop in Billings, I had a 2020 Freightliner come in with a bad DEF quality sensor code. The manual says to flush the line, no big deal, right? Three hours later I'm still fighting with the connector under the cab, it was totally frozen solid with crystallized DEF. Had to cut the line, replace the whole section, and the new connector was another 45 bucks. What should have been a one hour job ate up my whole afternoon. Anyone got a good trick for keeping those lower line connections clean?

The 5 micron fuel filter is a waste of money for most on-road trucks

I keep seeing guys at the shop and online pushing the 5 micron absolute filters like they're a magic fix. For a fleet truck pulling a dry van on clean interstate diesel, that's overkill and just costs more. The factory 10 micron setup is built for that fuel and protects the injectors fine. I've pulled apart pumps from rigs with 300k miles on the standard filters and the wear is minimal. The extra restriction can actually cause more issues in cold weather. Has anyone else seen problems from running filters that are too fine for the job?

Cousin thinks my diesel shop time is for family favors, and I'm divided

My cousin dropped off his pickup with a noisy injector, expecting me to sort it over the weekend. Part of me wants to just fix it to avoid drama and keep things friendly. On the other hand, a mechanic I respect says always doing free jobs teaches people not to value our skills. Where do you all stand on working for relatives or close pals?

My socket set keeps mixing up after working in the home garage.

What's a cheap way to label drawers so I can grab the right size fast?

Serious question, my kid's teacher asked me about DEF at parent night

Was totally caught off guard when she brought up diesel exhaust fluid during a chat about school projects. It made me see how diesel stuff comes up in weird social moments now.

During a routine service, I realized our trade's role in clean air.

A tuned engine doesn't just run better, it breathes easier on the environment.

My stance on overnight parts delivery just shifted after a clutch job.

Waiting for the correct flywheel taught me patience pays off in the long run.

I dismissed electronic diagnostic tools as unnecessary complexity until a persistent missfire on an International DT466 proved me utterly wrong.