Jump to content


Porch Pup
  • Content Count

  • Joined

  • Last visited

Community Reputation

22 Excellent

About Rockwell

  • Rank
    Old Iron Expert

Profile Information

  • Gender
  • Location
    New Jersey

Previous Fields

  • Make
  • Model
  • Year
  • Other Trucks

Recent Profile Visitors

2,051 profile views
  1. Happy Thanksgiving to all! And to my fellow Truckers, Happy Turkey Day and THANK YOU, From the turkey on my plate to the fork we eat it with, and everything in between, over, and under. This is one household that KNOWS how it got to us. THANK YOU for the long days, cold nights, days away from home, and the unending miles. Thank YOU driver for a wonderful Thanksgiving with my family. Stay SAFE and Keep On Truckin, (America needs you to , whether they know it or not.)
  2. No, keep the EPA dirt bags here and send ME back! Trucking was FUN! Made better money and the trucks literally had a soul. My Granddaddy and Daddy wouldn't even recognize what they call truckin today.
  3. Obviously this can be many things. I dont know how this would relate to the One Box DPF/SCR set up you probably have with a 2016. On older models like mine where the units are separate, I know DEF fluid can build in the pipe leading from the DPF to SCR. This build up can form a large rock like substance of odd shape that can change position in pipe as truck moves. So laying still its creating lets say a 30% exhaust blockage, but when moved, the shape now creates a 70% blockage, reducing power. Turn another corner, or hit another bump, the "Def block" in the pipe rotates and BAM power is restored as now its back to only 30% blockage. On earlier models, its super easy to check, simply remove the braided flex from the Obama Can (DPF) to the SCR and look inside the SCR. Again, I dont know hoe this might relate to a 1 box unit. Just a thought. Good Luck.
  4. MackTech, thank you for the response. I have to assume the truck does have rollover stability. Another symptom I've noticed when the idle races after setting parking brake. My exhaust temp guage Instantly pins itself far right and my HEST light comes on, as if exhaust temp instantly went thru the roof. If I release the parking brake and drive 10 feet, HEST light goes out and exhaust temp guage returns to normal instantly. The high exhaust temp reading is false, its only high electronically, not in reality. i did have the truck do this high idle with brake to me about 2 years ago. Mack installed new batteries while it was at the dealer shop. When i got it back, I got this symptom. I noticed they had hooked the ACM power wire to a different positive battery terminal than where it was with the old batteries. I put the ACM wire back to the original battery terminal and the problem went away. Now I know logically this dont make sense, and perhaps the resolution was just coincidental and had nothing at all to do with ACM wire. Two years later, the truck starts racing when I apply the parking brake. Some days it will do it all day, everytime. Other times it will disappear for days. Could it possibly be a weak battery causing this? Maybe a slight drop in voltage playing games with the computer? Whatever it is, it does not and has not affected operation of truck.
  5. 2011 CXU613, MP8 630K miles. Hey all, So here`s a weird one... This problem went away as mysteriously as it came. Yesterday, every time I set the tractor parking brake, (Yellow Air Valve on dash) the motor would race up to 1200 rpm, drop to about 1000, rev back up, then drop to idle and idle normally. Every single time I set the tractor parking brake. Other than that, truck performance was fine with all gauges reading normal, no MILS or codes at all. The problem disappeared towards the end of day and it hasn't done it again, including all day today. Any ideas?
  6. Make sure it is not leaking from gasket where the ccv meets the block. Mine had a really bad leak from there, not the orings on the ccv. Quick easy replacement.
  7. Forgive my ignorance, I'm no true mechanic, just Shady Tree, but how or what is a pressed on cam lobe??? Lobes pressed onto an otherwise perfectly round shaft??
  8. As far as I'm aware and have heard, through no qualified source, emergency vehicles do not derate. Yes you get all the same warnings and Mils, but no derate. It is my understanding, they aren't exempt from emissions, but they are exempt from derate.
  9. I was able to get a gasker kit no problem for mine thru H&H Mack, Rockaway, NJ. Maybe you can order it from them and have it shipped. My gasket turned brittle cause a leak. Simple, easy fix.
  10. I have been hearing this exact statement for 3 years now in US and haven't seen it yet. I`m sure eventually it will be reality, all depends on how much money the DOT thinks it will bring in. Investment and Return!
  11. Just in case it helps another down the road... Problem Solved. Engine harness behind engine fan had a short in the 5. volt sensor supply wire. 1 beer for fjh! You called it.
  12. Thank you fjh, what's funny is Mack installed a new starter, got the truck back and had this problem on first run out. Awefully coincidental. All starter wires bright and tight.
  13. Hello, 2011 Mack CXU613 MP8-445 600,000 miles(10speed) Motor intermittently stumbles or jerks on hard pull when calling for boost. Then returns to normal. When the motor stumbles, my boost pressure goes from let's say 33 to flat line. Not zero, just two dashes as if there is no reading or boost whatsoever. Looks like this... 33... Motor stumbles and display reads - -. Then it returns to normal. No codes being thrown. No other symptoms. Pressure Sensor? Actuator? Any ideas would be greatly appreciated!  Truck had had new injectors/cups and fuel filters are good. Even at idle, boost pressure will go from 2 or 3 psi to - - momentarily on center display.
  14. I need to do this same exact thing but waiting till warmer weather. I have the replacement kit. When I bought it, I had found a great YouTube video on how to replace, give it a search. As I recall, you remove the filter and push the valve out thru the top. Let me know how it goes for you! Good luck!!
  15. So would it then be wise to rebuild the heads at about 700k? Or no, to costly?
  • Create New...