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Challenger last won the day on January 3 2017

Challenger had the most liked content!

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About Challenger

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    BMT Veteran VIP
  • Birthday 12/06/1978

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    Pittsburgh Pa

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  1. Check your EPDM for corrosion. The epdm is the fuse box behind the clutch pedal or where the clutch pedal would be. The windshields would leak and water runs all over the epdm causing corrosion. Pull a few relays out and check them. Mack added a little rain coat to the epdm to keep water away. But I still see the with corrosion Had a truck where one headlight would turn on when the truck was sitting in the rain over night.
  2. Challenger

    Looking For Brake Switch Location CXU613

    Pretty sure they are behind the brake pedal and throttle pedal dash panel. Those sensors and wires are kind of “stuffed” behind that pedal. Like a rats nest
  3. Challenger

    Mack CH613 no top end power

    No fuel, no boost Fuel and boost pressures are the main things I check with low power complaints. You need to check your fuel pressure I put a fitting in the fuel galley plug and use 1/4” airline and the air pressure gauge (same as the one in the cab). I use green needle for fuel and orange for boost. It’s not fancy or “techy” but it gets the job done. I like to keep it simple. The fuel galley plug that I use is in the front of the engine, left side, directly in front of the EUPs. Under the AC compressor if you have one. It’s a 1/4” square plug. I use a 1/4 extension and ratchet to remove the plug.
  4. Challenger

    Mp7 no fuel to head

    If a new part has to be repaired, the customer should pay for a used part, not full price. But we all know that isn’t going to happen. I’ve always sent them back. But then again, the customer is probably losing more money with the added down time on waiting for a new part to show up. Good to know Macktech689. Thanks
  5. Challenger

    ECM Programing

    VMAC III isn’t even that old. I can understand dealers not having anyone with VMAC I and II, and older Volvo experience. But VMAC III? That’s sad. Nothing like going to a dealer and having some apprentice tech with maybe a year experience telling you what you need. These are the guys putting engine harness on gray engines like they’re MP engines. “You need a set of injectors and an engine harness.” Today’s Mack dealer
  6. Challenger


    If the front rear carrier had a spacer behind/before the yoke, it would need switch to the new rear. I’ve seen people leave them off, with the complaints of, vibration, oil leak or noise. Ratios are are stamped on the front right flat spot on the carrier. To the right of input, facing forward
  7. Challenger

    UPS and Mack

    Probably because they were 1 cent cheaper. UPS is loyal to money, not truck makers.
  8. Challenger

    CHU MP8 Dead outside the firewall

    Did you try unplugging and plugging the connector back in. It’s possible while reinstalling the connector the piece inside the cab slide inside. Unplug the connector and plug it back in. Be careful not to overtorque or cross thread the bolt that holds the connector together
  9. I would take it to Mack and have all softwares updated. Maybe a communication problem between ECUs. Maybe mid 140 (dash cluster) isn’t getting needed info from other ECUs. That would explain why you have the same problem with another cluster, possible comm problem would still be there.
  10. Challenger

    mack 18 speed problem

    Sounds like the shop doing the work doesn’t have a lot of gear experience. You’re better off with the reman instead of some fresh out of tech school apprentice learning on your trans.
  11. Challenger

    mack 18 speed problem

    Mack syncrhos starting failing in 2003. This is when I started doing inframe repairs. First they said it was range shifting in reverse that was breaking snaprings. So they updated the aux mainshaft with thicker snap rings and grooves. Synchros kept failing. Then it was the synchro shift fork bolt loosen up and causing incomplete shifts and eventually failure. So start checking torque on the bolt but Synchros kept failing. So they updated synchro, lo and hi gears. Guess what , you still see failures. Then you have the barrel trans cooler under the “cactus” hose failing and pumping coolant into the trans destroying Synchros. Seems like the T2 trans where doing well, then they got cheap with the T3s, it’s never been the same. Have synchro failures actually ever been eliminated? I would say no. Updated this, updated that, is something that dealers say to make you fell better.
  12. Challenger

    Allison code P0843

    Have you replaced the trans fluid and filters? Seems like people overlook trans fluid and filters. Fun fact- The original trans filters say “factory installed”.
  13. Challenger

    Jake brake troubles

    low side-1 head High-both heads Truck off, run power to the terminal sticking out of valve cover. They should make a "click" noise when the power makes contact. Click-good solenoid. No click-broken wire to solenoid or bad solenoid. You could also let truck idle and hold power to the same terminals (1at a time) and the engine brake should turn on (you'll hear brake) If you heard both solenoids click, but still have only 1 head working when you ran power while running, it could be- Loss of oil pressure in engine brake housing examples- split orings on solenoid most likely the bottom oring, missing plugs at the end of rocker shaft (plugs look like little freeze plugs), valve/ engine brake adjustment (in my experience this is more of a red engine problem MP8), Jake Brake needing updated
  14. Challenger

    aset valve adjustment

    7 inch/lbs

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