Onyx610

Couldn’t get the bulletin for you so I just copied it for you. “A coolant level sensor that is leaking internally can result in damage to the engine electronic control unit (EECU) due to coolant “wicking” or migrating down the harness. To prevent this from occurring, an anti-capillary jumper harness (part No. 41MR31560M) has been developed. Whenever a coolant level sensor (part No. 64MT466) is replaced, installation of the jumper harness is recommended. If a leaking coolant level sensor is encountered (as evidenced by coolant inside the harness connector), replace the sensor and install the anti-capillary jumper harness. Additionally, disconnect the J1 connector from the EECU and check inside the connector for signs of coolant, and also check the connector pins for signs of corrosion. If the pins are corroded, replace the EECU and the engine harness. When installing the new sensor, hand-tighten the sensor until snug, and then use an accurately calibrated torque wrench to tighten the sensor to 35–40 lb-in (4.0–4.5 N•m). DO NOT exceed 42 lb-in (4.8 N•m) MAXIMUM torque. Connect the jumper harness to the coolant level sensor, loop the excess harness and use tie wraps to secure the loop. Connect the other end of the jumper harness to the engine harness connector.”

https://class8truckparts.com/mack-truck-20838672-wiring-harness.html pull the connector at ecm to make sure the coolant didn’t make a trip there.

Sounds like something is expanding due to heat and causing your issue.

Cylinder may need rebuilt. A good dump body company could hook gauges up and diagnose it for you most likely.

🤣 keep them coming, we will be here…

Even though you may be replacing a lot of parts to find a leak, the learning experience is worth every penny. Your doing a good job. 🍻

“Kidney valve” is the spring brake relay valve. The one you have apart is the service brake relay valve. The little valve with the red line and green line is just a double check valve. That valve on the cap of the valve you have taken apart is the “anti compounding valve” prevents a double application of braking power when the parking brakes are applied and you press the brake pedal. It could be part of your issue.

You can take these valves apart and clean them up and re grease them.

Not if your “automatic slack adjusters” are working correctly….

I’m going to say your truck is not setup correctly. The clevis on your chambers are hitting the mounting bracket and preventing the brakes from fully releasing and probably from auto adjusting. Setting up a chamber to the correct length isn’t always as easy as it seems.

Do you have to have your brakes adjusted?

Not only should it not go past 90 degrees, they should be setup to be at 90 degrees with brakes applied. Maximum brake power at 90 degrees. Your brakes are not setup correctly.

You need to cage it and cut it to length. There is nothing wrong with them.

Engine speed sensor

Also to add to the leaking shaft, temp change…

You should have to put some effort into trying to rotate it. Some like on the ASET engines are extremely hard to move by hand.

Oil in the tanks means compressor is on the way out, there is an allowable limit of oil to water. Oil in the air system ruins air dryers and creates problems for the air valves.

Getting oil in the tanks? You could have a stuck unloader valve. Take them out and clean them. Or just get a unloader valve kit.

In the side

More then likely a bad actuator, but check the harness and connectors first.

Eaton advantage easy pedal

I wonder why they didn’t just put a new trans in? 🤷🏼

Ahhh ok, yes that is a good possibility.

How long of an idle does it do this? Bump the idle up when idling for longer periods. See if that clears it up. Could be “wet stacking”