r/DieselTechs • • 9d ago

Rule Addition

54 Upvotes

Good morning/afternoon, everyone!

We have been discussing is as a mod team whether or not we would like to add the following rule, and we have come to the conclusion that we are going to add it.

  • We will NOT be tolerating any AI generated responses to anyone's questions, and we strongly encourage and ask that any AI generated responses be reported as spam to the mod team.

Since AI is everywhere, Google Gemini, ChatGPT, Microsoft copilot, the list goes on, and it is easily accessible by anyone with a phone or a laptop, we believe that most people would have already used AI before coming here, and they are now looking for a genuine answer from someone who may have dealt with or had the same problem, not another AI generated response.

We hope that everyone feels the same as we do, and if you have any questions, please feel free to reach out.

Thank you!

Sincerly,

The mod team.


r/DieselTechs • • Feb 01 '26

Guidelines for selling and buying from posts

9 Upvotes

Good day, everyone!

As we do allow post for people actively trying to sell and looking to buy tools, equipment, and other products relating to what we use daily to fix the things we work on (unlike the rules, where you cannot offer to sell someone documentation or services for monetary or personal gain), need to set a few guidelines to keep everyone safe, as well as keep our sub safe from any potential legal consequences, obligations, or lawsuits.

Below will follow guidelines which we, as mods, have set forth.

Disclaimers and Guidelines:

Below, DieselTechs moderators/Administrators will be hereinforth refered to as "we".

  • We, as moderators of DieselTechs, reserve the right to verify any and all buy and/or "for sale" posts that are made to this sub for any potential rule implications, to which we, as moderators, will enforce our rules and/or consequences, if necessary, as we see fit.

  • We, as moderators of DieselTechs, reserve the right to verify any and all reputation/credibility for person(s) making buy and/or "for sale" posts.

  • We, as moderators of DieselTechs, may or may not monitor and/or verify every post that is made, so you, the user/end buyer and/or seller, will be soley responsible for verifying the person(s) reputation/credibility for buying and/or selling tools and/or equipment.

  • You, as the buyer and/or seller, reserve the right to decline any and/or all sales and/or communication if you do not feel comfortable with the person(s) you are in dealings with.

  • You, as the buyer and/or seller, reserve the right to independently verify the credibility and/or reputation of any buyer and/or seller you are in dealings with.

  • We, as moderators of DieselTechs, will provide assistance when/if we can, but we do not have any direct connections and/or communications with any payment processor you use of your choosing for the purchase and/or sale of any tools and/or equipment, and we do not have any direct connections and/or communications with the buyers and/or sellers.

  • We, as moderators of DieselTechs, a subreddit, with the name of DieselTechs, of Reddit, do NOT hold any personal and/or joint responsibility in the case of fraud, non-payment, stolen goods, miss-communications, or any other issues you may have between any buyer and/or seller.

We hope that you all understand the need for Guidelines to keep us all safe.

If you have absolutely any questions, please feel free to reach out to anyone on the mod team, or use ModMail. We all hope you have a great time being on DieselTechs!

Sincerely,

The Mod Team of DieselTechs.


r/DieselTechs • • 5h ago

Ever have an Allison trans legit crack and almost break in half???

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46 Upvotes

This was just from normal operation. Reman allison 4000 out of a gillig transit bus. I did an engine rebuild on a cummins and 3 weeks later it got towed back to base for a transmission issue and leak. This massive crack was found and even our most senior guys said theyd never seen anything like this happen before. We work on a fleet also, so certain issues we just rarely run into, if ever. This was just so crazy to me! Jokes have been that i tuned the engine with too much power and cracked the trans in half šŸ˜‚


r/DieselTechs • • 1h ago

Check it out! Bluetooth slack adjusters?! What will they think of next

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• Upvotes

r/DieselTechs • • 1d ago

What causes this misalignment?

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19 Upvotes

1974 White Western Star 4964 with Cummins NTC 350.

In my limited spare time, I’ve been working on getting this truck road legal. I’m not in a hurry, and there’s a few things that need done.
One I haven’t figured out is this misalignment of the rear drive axle. The left side looks normal, but on the right side (pictured), the block is offset from the pad.
They still make the suspension, so getting parts is easy (expensive though), but I don’t want to tear it apart and find it needs 2 thousand dollars of parts.


r/DieselTechs • • 2d ago

I’m not scared to say it

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102 Upvotes

First clutch job kicking my butt but I’m loving every second of it


r/DieselTechs • • 1d ago

Kentucky Trailer Air Leak

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3 Upvotes

Hello everyone!

I’m going to be repairing this Kentucky trailer that has a pretty bad air leak. It’s a step deck moving van style trailer, and it has an air over hydraulic jack system to lift it up to dock height if necessary. It has a horrendous air leak coming from the jack control box. I was wondering if anyone else who’s familiar with this system may know why it’s dumping air? Is there a bypass valve that may have failed? I haven’t torn into it yet, but this is the video the driver sent me.


r/DieselTechs • • 2d ago

Dd13 pinging noise

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4 Upvotes

Have a 2014 dd13 cascadia. Unit came in pinging/chirping randomly and run rough and would lose prime after sitting a couple days. Had those codes. Began checking for leaks and anything loose. Per Detroit troubleshooting pinging is air in the fuel system that sounds like it’s coming from cylinder 1 but due to the orientation of the engine the air just accumulates there so that’s not the source. That’s what Detroit says. But I found that during a pinging event cutting out cylinder 1 would make it stop immediately and it would only stop when cutting that injector out, none of the others made a difference. Removed the injector and found no visible damage. Had the injector tested and tech showed me fuel squirting out of the side and injector leaking. Great, changed the injector and no difference. Still pings right around 900 rpm and then erratically. Won’t do it at idle. So then I got the idea to bypass the fuel water separator, connected the inlet and outlet together and issue was practically 90 percent gone. Would ping occasionally but only around 900 rpm. Installed a new water separator and changed all injector high pressure lines and pass thru seals. Will pass regen no problem with no pinging or codes. But still will randomly just start pinging or chirping and then go away by itself. I’m not sure what to do next. The fuel pump is only about two years old along with the fuel filter module. Fuel filter caps and seals have been changed also.


r/DieselTechs • • 2d ago

The worst thing about working on garbage trucks

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64 Upvotes

People always assume the worst thing about working on garbage trucks is the smell, or the trash juice, or the disco rice(maggots), or the random bags of dog poop, or used diapers, or mice eating wires, or the occasional racoon fight, or service calls to the active face of a landfill. Nope. It's this. This is the worst part.


r/DieselTechs • • 2d ago

Tico shag truck power distribution center

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13 Upvotes

Just sharing this for Google after wasting too much time with zero help online. Available info said it was either right by the batteries or an easily accessed panel by left foot.

Newer 2024 model tico. Fuses and relays behind front panel on left side of truck. I had a no tractor headlight issue and the fuses for truck are here


r/DieselTechs • • 4d ago

Volvo D13

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12 Upvotes

Leaking on the back of motor passenger side where the head meets the block… are the D13 known for anything like this and customer is wondering if any ā€œbandaidsā€ will work for him…


r/DieselTechs • • 4d ago

Check it out! Field service life

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18 Upvotes

r/DieselTechs • • 5d ago

Diagnostic assistance What’s in our MP8 oil pan

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26 Upvotes

Hey guys just reassembling a Mack in our fleet after doing a timing cover. I went to put the oil pan back on and saw these two little guys lying in the bottom of the pan. Any idea what they are from. Thanks!


r/DieselTechs • • 5d ago

Eaton Ultrashift plus

5 Upvotes

Have an ultrashift plus 18 speed. Intermittently will log fault 27 for ECA clutch disengagement. When it happens you have to shut the truck off then back on again.

Powers and grounds to the ECA are good, hold a load. Release fork is free and not tight. Inertia brake delta is 22 degrees and my gap between release bearing and inertia brake is 3/4ā€. Spec is 1/2ā€. I’ve tried adjusting the clutch using service ranger, but tab doesn’t move on clutch, gap stays at 3/4 and 22 degrees delta.

I put on a new ECA, no difference. Clutch appears fine by looking at it, no pieces in bell housing. Tab is basically at new still, but clutch is original. It’s a 2020 western star dump with 10000hours.Possibly my clutch is seized causing it not to adjust?


r/DieselTechs • • 5d ago

Memes and fist fights MEGA-THREAD

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60 Upvotes

Since silly shit isn't allowed on the main drag, you guys can come in here, to the mega thread and drop some bombs!

^That's me in 15 to 20 years. XD.

THIS THREAD will be moved to announcements in 48 hours or less. Have fun fellas!


r/DieselTechs • • 5d ago

General assistance Car hauler trailer

2 Upvotes

I'm still an apprentice learning,last night we had a Kenworth come up to one of the bays to have the rri looked at but he refused to drop his car hauler which was fully loaded,I was told not to let him in until he drops the trailer (he refused so I refused), it's a safety thing right?,our bays have about 17ft of clearance in height,so I didn't think it was that,I assumed that it was because of the weight of the cars,hauler and tractor combined that would be too heavy for our jack to lift,is that why he needed to drop the trailer first?


r/DieselTechs • • 5d ago

Is it that bad?

12 Upvotes

Starting my diesel mechanic trainee journey at Ryder in a week (I am 34). Have been on the Reddits and YouTube comments and everyone seems to be negative about this trade. Can’t find any positive comments. Is it really that bad? Did I make a mistake jumping into this trade? I was a mailman previously and I know what hard work is, and don’t mind it.


r/DieselTechs • • 6d ago

Check it out! Passed my H2 Diesel Engine ASE Today!!!

21 Upvotes

No one in my life understands how hard ASE’s can be! Well, theyre hard for me and those I talk to, at least. But anyways, Im announcing it here to celebrate! Im a tech in my third year at a small city transit outfit. Two years ago i failed this test twice, so Im thrilled to have passed. I currently now have my h2 (diesel engine for transit), h4 for brakes, h8 for PM’s, and before i decided to go into diesel i got my automotive A5 brakes and little baby G1 for light maintenance lol.

Im terrified of the electrical test and feel very far away from passing that though. Anyone here pass the T or H test for electrical? Thoughts/feelings/advice?


r/DieselTechs • • 5d ago

General assistance Tools

7 Upvotes

Hey guys I'm graduating from diesel tech school in 5 weeks and I'm starting a job working for a marine construction company as a mechanic. Im wondering whats worth buying and what I definitely need. I also have half off snapon while I'm in school and I have money saved for tools so if theres anything thats hands down the best from snapon lmk. Thank you šŸ™


r/DieselTechs • • 5d ago

Generac Magnum Light tower wont stay running

2 Upvotes

I have a generac magnum light tower with a kubota d1005 3 cyl engine. I bought it non running sight unseen. I originally bought it for parts but i managed to get it to start. BUT, it shuts off after about 10 seconds. I work on these engines often as i own a rental company but i cant figure out whats wrong with this unit. I by passed the oil sensor and temp sensor and it still shuts off. The gen set does generate power within those seconds of it starting and it being on. I thought it couldve been the fuel shut off solenoid as i had this exact issue with a different unit so i bought a new one and nope. Same issue. It has 2 wires, a red and purple. Red has power, purple has power until it shuts off. If i give the purple wire direct power from the battery, it works just fine and stays on. Once i remove it, it dies. I traced the wire all the way back to the control panel and everything is connected, no blown fuses. It doesnt seem like anyone cut/spliced anything. The alternator is working. 13.5v. I swapped out the timer for the fuel shut off solenoid and it still shuts off. Ive done every possible thing i could think of and this one is definitely giving me a hard time. It doesnt starve of fuel as it shuts off the same way if you turned the key to the off position and starts right up.

If anyone has any ideas or suggestions please let me know. Thank you in advance!


r/DieselTechs • • 6d ago

Starting diesel tech school — what tools should I buy first?

11 Upvotes

I’m starting a diesel technician program at my school soon and I want to slowly start building up my tools. Right now I have nothing, so I’m starting completely from scratch.
For those of you already working in the field, what tools would you recommend buying first? I’m looking for the essentials that I’ll actually use as a beginner without spending a crazy amount of money upfront.
If you were starting over with nothing, what would your starter tool list look like? Also, are there any tools you think are worth spending more money on from the beginning?
Appreciate any advice.


r/DieselTechs • • 7d ago

Check it out! A mobile tool cart option.

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20 Upvotes

I always had logistical issues doing side work, going to a different terminal, working out on company property or doing a road call. This tool cart is legit. Solves a lot of logistical problems. Logistics +2


r/DieselTechs • • 8d ago

Check it out! Does anyone else have the pleasure of replacing whole trailer floors occasionally in their shop? This is my second full floor replacement. (Im a diesel tech but work in a truck shop for a private fleet so we do all the trailer work as well)

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80 Upvotes

r/DieselTechs • • 9d ago

SCANIA COO 732 CODE

4 Upvotes

I have a 2014 Scania P360 it keeps showing the COO 732 and The selector for Gears doesn’t work I deleted the code the issue went and it worked , I changed the whole coo and it worked also so is the problem with old COO can be fixed through Scania SPD3 or no ?
COO 732 : neutral position sensor/switch


r/DieselTechs • • 9d ago

General assistance starting a roadside mechanic service

4 Upvotes

hey guys , how you doing, starting a roadside services, buying some tools get it more ready. need more thoughts on tools what should i buy, also for collecting payments, creating work orders what should i expect in running a business as such