Foothills Group Lethbridge

Service manager: "20 minutes."
Mechanic: "To find it or to fix it?" 😭🔥

🔧 Duramax 6.6 Diagnostic Training
This truck came in hunting, surging, and struggling to idle.
The fault codes pointed us toward the MAF circuit, but instead of throwing parts at it, we started testing. Along the way, we found a temporary solution that helped the truck idle properly while we continued tracking down the real issue.
A good reminder that a fault code tells you where to look — not what to replace.

Fault code says MAF sensor.
You have 30 seconds before your boss orders parts.
The parts cannon would have got the wrong result!!
What's your next diagnostic step? 👇

Why disconnecting the MAF is a short term fix! Sure it can run but it will for sure have problems, it did get us running to keep troubleshooting.

Today's training truck: Duramax 6.6
Under throttle, the engine starts hunting and surging before eventually leveling itself out. That kind of uneven fueling or airflow usually means there's a deeper issue hiding somewhere in the system.
For now, we found a temporary way to get the truck idling properly while continuing the diagnosis.
And that's the important part: temporary.
A temporary fix helps confirm a theory and keep the troubleshooting process moving, but it doesn't mean we've found the root cause yet. The real repair comes after the diagnosis is complete.
Stay tuned as we continue tracking down what's really causing the problem.

Some actually GOOD news came out of 2025 👀
The old paper timing cover gasket had a bad habit of blowing out and causing leaks over time.
Now it’s aluminum reinforced — same bolt pattern, way stronger design 🔧
Tiny upgrade… massive difference in reliability.

We recently saw a comment asking why we'd replace a seal if it isn't leaking yet.
The answer is simple: good mechanics don't just look for failures — they look for warning signs. 🔧
Not every leak is visible. A Level 1 leak may look wet but has no active drip. It won't fail inspection, but it's something we document and keep an eye on.
Preventing problems is always cheaper than repairing them later.

Customer complaint:
“The truck feels like it’s steering itself down the road.” 😭
Turns out excessive play in the steering gear travels all the way through the drag link and steering arm… letting the wheels shimmy around even while the steering wheel looks straight 🔧
Tiny steering slop = major highway anxiety.

That’s not dirt layering… that’s years of rust jacking eating the steel from the inside out 🔧💀
When rust builds between steel plates, it slowly forces them apart until one hard impact can make the whole thing let go.
This is why inspections matter more than people think.

Started with a parking brake issue…
ended with our mechanic digging through mud, tape, and a destroyed harness just to find ONE broken wire 😭🔧
Sometimes the whole machine acts possessed because of something smaller than your pinky finger.