c/diesel-mechanics

Tried a cheap fuel injector puller vs a Snap-on one. Night and day difference on a 6.0 Powerstroke last week.

The cheap one kept slipping and I almost stripped the threads. The Snap-on grabbed first try every time. Cost me $180 more but saved me 2 hours of cussing. Anyone else find certain tools are just worth the splurge?

Tried to save a buck on a water pump, ended up stranded on I-35

Last Tuesday I figured I'd throw a cheap rebuilt water pump on my F-650 instead of shelling out $250 for a new one. Made it about 12 miles down I-35 before the bearing seized up and the fan exploded through the radiator. Had to call a buddy with a flatbed to haul me back to the shop, cost me more in time and a new radiator than if I'd just bought the good part.

That older driver at the terminal made me rethink my whole idling habit

I was sitting at the Pilot in Gary, Indiana last week keeping my truck running during my 30 minute break. An old guy pulling out next to me rolled down his window and said 'you know that's $8 an hour you're burning up in fuel and wear.' He showed me his logbook where he tracks every idle minute. I never really added it up before but he was right. Anyone else here actually track idle time and seen what it costs you?

Lost $300 on a cheap injector puller lesson learned

I tried saving money last month on a Harbor Freight injector puller for a 6.0 Powerstroke. Broke on the third injector and jammed the tool inside the head. Cost me $300 for a shop to extract it and buy a real OTC puller. Anyone else have a cheap tool fail and cost way more than the good one would have?

PSA: That $60 harbor freight tool cart saved me 2 hours on a job last week

Honestly, I've been using a beat up Snap-On box for 8 years and thought upgrading to a new one was the only way. Then I grabbed the cheap HF 4-drawer cart on a whim for a quick roadside job near Austin. It rolled fine, held all my wrenches and impact, and I didn't care if it got muddy or dropped. For mobile work or backup storage, it's hard to beat for the money. Anyone else find a cheap tool that actually works better than expected?

Switched from a dial indicator to a digital setup for injector timing on a 12-valve

Got a 1996 Cummins in the shop last month, owner wanted the pump timing checked. I always used a dial indicator with a magnetic base, but I finally caved and bought the OTC digital timing kit for $180. Took me about 45 minutes to get it set up and zeroed on the number one cylinder. The digital readout was way easier to read than trying to squint at those tiny marks on the dial. Got the timing dialed in to 13 degrees BTDC and the truck fired right up no smoke. Anyone else switch to digital and never look back?

Had an injector blow a line on I-94 outside Detroit last Thursday

I was hauling a load of steel coils up to Flint when I heard a loud pop and suddenly lost power. Pulled over right near the 8 Mile exit and found the number 3 injector line had cracked clean through from vibration. Had to call a mobile mechanic who brought a replacement line and got me going in about 2 hours. Anyone else run into injector line failures on older Cummins engines?

I finally fixed that Cummins ISX that kept throwing a fuel pressure code

Spent 3 days chasing a P0087 low fuel pressure code on a 2015 ISX at my shop in Tulsa. Turns out it was a worn-out gear pump drive pin that cost $12 but took 18 hours to diagnose. Anyone else run into a phantom fuel issue that wasn't the CP3 or lift pump?

Had to choose between a dealer shop and an independent garage for a major job on a 2017 Freightliner - which side are you all on?

I picked the independent shop because they quoted $2,800 versus the dealer's $4,500 for a turbo replacement, and the job took three extra days and still had a boost leak, so was saving that money really worth the headache or do you guys swear by dealer work every time?

Caught a guy at the parts counter ranting about synthetic oil in older Cummins

He was saying how he flushed 15 quarts of Rotella through his 5.9 after 200k miles of conventional and it started leaking from every seal. Made me realize I've been babying my rebuild with fancy oil when the old stuff probably kept the gaskets swollen. Any of you guys run conventional in high-mileage engines on purpose?

I called BS on electric fuel pumps for Diesels until my mechanical one left me stranded on I-80

Ran a 1996 F-350 with a mechanical lift pump for 8 years. Told everyone electric pumps were overkill and a waste of money. Then last month coming back from Cheyenne the pump started ticking funny. By Evanston I was dead on the shoulder at 2am in January. Cost me $450 for a tow and $280 for a roadside mechanic to get me to a shop. Swapped to a FASS electric pump the next day. Truck starts faster and no more worry about losing prime. Any of you guys made the switch and regretted it?

Swapped to a synthetic 5w-40 and saw oil temps drop 15 degrees in my Freightliner

I was running conventional 15w-40 for years in my Cummins ISX, figured heavier was better for a high-mileage engine. After I switched to Rotella T6 last month, my oil temps went from 215 to 200 on the same hill climb. Any of you guys see that kind of drop with full synthetic?

Saw a rookie change oil on a Cummins ISX and skip the torque wrench on the drain plug

Guy at the shop in Wichita last week just cranked it down with a ratchet, said he's been doing it that way for years. That pan is aluminum and the plug is steel, overtorque it once and you're helicoiling a hole in a $600 oil pan. How many of you have seen stripped threads from this exact mistake?

The old timer who called me out on my valve adjustment at a shop in Tulsa

I was doing valves on a 6.7 Cummins a few months back at Brown Diesel in Tulsa, and this retired guy named Walt watched me for like 5 minutes. He said I was going too fast and not feeling the pushrod drag right. I was sure I had it down, but next time I slowed way down and actually paid attention to the drag, and sure enough I caught two that were off. Has anyone else had an old timer give them a tip that totally changed their technique?

Debate: Should we still rebuild old Detroit engines or just swap in remanufactured ones?

I've been going back and forth on this since a job in Flint last spring. Old customer brought in a 1995 12-valve Cummins with 400,000 miles on it, had a cracked block and a bad head. I spent 3 days figuring out if we could save it versus just dropping a $4,500 reman unit in there. On one hand, rebuilding keeps the original numbers and history, plus you know exactly what's in there. On the other hand, a reman comes with a warranty and takes half the labor time. Which way do you lean on older rigs like that when the bill gets close to the truck's value?

Used to fight with stuck injectors for hours until a guy at a truck stop in Flagstaff showed me a trick

I'd always just reef on them with a slide hammer and a prayer, usually ending up with a busted knuckle or a stripped thread. This old timer saw me struggling and told me to let the engine cool completely, then hit the injector body with a heat gun for a solid minute while turning it with a wrench. The different expansion rates break the carbon seal. Tried it on a 6.7 Powerstroke last week and it popped right out. Anyone have a different method for those really stubborn ones?

A talk with a farmer near Topeka made me question the 'always use OEM parts' rule

I was working on his old John Deere 4020 last week, the one he uses for everything from tilling to hauling. He needed a new water pump, and I told him flat out to get the Deere part, that the aftermarket ones are junk. He just looked at me and said, 'Son, I've run this tractor for thirty years. The last three pumps were from the parts store in town, and each one lasted me eight seasons. The one factory pump I tried gave up after five.' That hit different because it wasn't just talk, he had the receipts in his shop book. It made me realize I've been repeating what I heard in the shop without seeing the long haul for myself on older machines. Maybe for a new rig under warranty, sure, stick with OEM. But for a workhorse that's paid for? A good aftermarket part can keep it running just fine. Has anyone else had a customer prove them wrong on parts like that?

Remember when you could just listen to a diesel engine to find the problem?

I was working on an old 7.3 Powerstroke last month that had a rough idle, and the computer codes were pointing everywhere. I spent a good two hours swapping sensors with no luck. My old mentor, a guy named Bill from the shop in Billings, always said to use a long screwdriver as a stethoscope. I finally gave up and tried it, placing the tip on each injector while it was running. On number three, the tick was way off, more of a dull thud. I pulled the valve cover and sure enough, the injector o-ring was blown, letting compression into the fuel rail. The computer saw the rail pressure swing and threw a bunch of false codes. That $2 trick from thirty years ago saved me from ordering a $300 high-pressure oil pump. Anyone else still use the old mechanical diagnosis tricks before trusting the scanner every time?

PSA: I thought those aftermarket fuel additives were a total scam until my old 7.3 started acting up

For years I laughed at the bottles of 'diesel performance' stuff on the parts store shelf. Figured it was just snake oil for people who didn't know how to maintain their rigs. Then my '99 F-250 with the Powerstroke began having these weird, random power losses, especially on cold mornings here in Spokane. It wasn't throwing a clear code, just acting sluggish. A guy at the truck stop, who looked like he'd seen a few things, told me to try a bottle of Hot Shot's Secret Diesel Extreme. I was desperate, so I dumped it in. Two tanks later, the rough idle smoothed out and the power came back. I guess the injectors were just gunked up after 250k miles. Still feels weird that a $25 bottle of liquid actually did something. Has anyone else had a legit fix from an additive they swore they'd never use?

Had a 6.7 Powerstroke with a weird injector knock that turned out to be a $2.50 o-ring on the high pressure fuel line.

Ever try to get a stuck bolt out with a regular wrench versus a proper impact? Had one on a Duramax water pump that wouldn't budge.

Spent 45 minutes reefing on a 3/4-inch wrench with a cheater pipe, nothing. Grabbed the 1-inch drive impact, three ugga-duggas and it spun right out. What's your go-to for seized hardware on older engines?

Had to pick between a cheap rebuild kit or a whole new turbo for a 6.0 Powerstroke

The customer wanted to save cash, so we went with the rebuild kit from a local parts house. It lasted about 4,000 miles before the bearings went out again, and now we're doing the whole job over. Anyone have a go-to brand for a full turbo unit that actually holds up?

Hot take: I used to swear by the old-school feeler gauge for valve adjustments on my 7.3 Powerstroke, but after burning a set last year, I switched to a dial indicator and it's way more consistent.

The feeler gauge method left too much room for error on worn rocker arms, so I made the switch after a buddy in the shop showed me his setup, and now I won't go back, what's your go-to method for setting valves on an older engine?

Warning: The new shop in Boise is using a different kind of fuel additive in their bulk tanks

I was picking up a part over in Boise last week and stopped by that new diesel shop on the main strip. I got talking to the owner while he was filling his bulk tank for the pump outside. He showed me the drum he was using, and it wasn't a standard cetane booster or anti-gel. It was this all-in-one formula that also has a lot of detergent and, get this, a lubricity enhancer that's not just the usual stuff. He swears it's better for the newer emissions systems and keeps injectors cleaner. But it got me thinking, is mixing all those jobs into one additive really smart? Part of me thinks a targeted treatment for the specific problem (like just anti-gel in winter) is the way to go, but he says his bulk customers love the simplicity. Has anyone else run into shops switching to these combo additives, and what's your take on them for fleet maintenance?

I finally gave in and tried that ultrasonic injector cleaner at the shop

Honestly, I thought it was just a fancy gimmick, but after clearing a persistent miss on a 6.7 Powerstroke that wouldn't respond to anything else, I'm a believer. Anyone have a different go-to method for really clogged injectors?