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Pedigreed Bulldog
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Everything posted by Mackpro

  1. Looks like my links were bad , but in the link, enter SB261016 or SB261014 in the “Keyword Search” to locate the bulletins, then click on the SBXXXX to view
  2. Also this bulletin as well . https://macktrucks.vg-emedia.com/ProductListing.aspx?keyword=SB261016 Click on the underlined SBXXXXX to view/save the bulletin
  3. Look at this bulletin https://macktrucks.vg-emedia.com/ProductListing.aspx?keyword=SB261014
  4. On our CHU’s and CXU’s , we have be having to replace the short harness from the front chassis harness up the the coolant level sensor. . Either the harness ends went bad or wires pulled apart inside the insulation.
  5. There are a couple of bulletins on this code. If a pre common rail MP8 engine , clear code and keep on trucking . If common rail engine then pressure test intake system , pay attention to charge air cooler/CAC for leaks .
  6. https://static.nhtsa.gov/odi/tsbs/2014/SB-10082801-0699.pdf These are the 2 bulletins we always followed and fixed the issues 99% of the time .
  7. https://static.nhtsa.gov/odi/tsbs/2016/SB-10083430-6903.pdf
  8. Grade Gripper is sticking and keeping brakes engaged/ slow to release. Mack has released a couple of service bulletins on this . It was a common problem. Fix was a new solinoid valve and quick release valve
  9. Factory/dealership HP upgrades for MP8 should be fairly cheap. If you have a Mack transmission and truck is out of warranty. The dealer cost to go to 505 is usually around $200 , the dealership will usually mark that up 30% or $100 and charge 1 hour labor to install it . If the truck is still under warranty the the cost of the download is the difference between the cost of the factory engine versus cost of a 505 HP engine at time of purchase. Usually $1200-1400 plus markup and labor to install . On some year models there is the 505 Plus download that has an extra 100 ft pounds of torque that
  10. The engine brake plungers are known to unscrew themselves and cause issues as well . Mack sent out a bulletin and tools to dealers to tighten the plungers . Every time we had the rocker arm shaft of a MP engine we would check the plungers and see if they were backing out https://static.nhtsa.gov/odi/tsbs/2017/SB-10090649-6903.pdf
  11. It’s for your cab power. They do go bad . Mack later changed the set up to a large fuse instead of the breaker style you have .
  12. Power comes through fuse 39 in the fuse box on the fire wall , then through the trailer ABS relay that’s in the same fuse box . Power comes out of that relay on wire # 39-B-5.0 that goes up to the trailer buss bar, then it’s connected to the blue wire that feeds the trailer
  13. On common rail engines, there is a electric fuel pressure solinoid on the end of the fuel rail under the valve cover . It was a common problem and we had all ours replaced with a new updated part number solinoid and also harness. It caused low fuel pressure problems and low power . There is a bulletin on this from Mack and is on both MP7 and MP8 engines
  14. Pull the fuel supply pump . Check for play in the shaft, should be none. You can spray soapy water on shaft while shooting air into the inlet and outlet abs check for bubbles, other wise here’s what we used to do . Put fuel dye in the primary (first filter) and run the engine for about 45 seconds to a minute. Shut off engine and cap off fuel return line on the side of the block above the air compressor. Hook a air pressure regulator to the inlet of the primary fuel filter inlet and pressurize to 40-50 psi . Drop the oil pan and use a black light and look for leaks. The EUP pumps will alway
  15. I’m my notes, on a 2010 emissions truck during a regen the boost is 1.8 to 2 psi, however it doesn’t say with or without DRV valve , only the first year or two on the 2010 emissions year trucks used the DRV , they later made a kit to delete it along with a software download
  16. Look at the bulletin in the next to the last post in this thread
  17. https://static.nhtsa.gov/odi/tsbs/2013/SB-10054292-5095.pdf this Bulletin might still apply even though yours is not a MRU/leu
  18. Is the oil level over full? Fuel in the oil is a likely problem.
  19. About 10-15 years ago I spent a lot of time trying to figure this same thing out . This was the days of many trips to Radio Shack for resistors . The temperature one was somewhat easy , I had it set to around 250 degrees. The flow meter side was a totally different thing . In the engine ecm it calculates and sets a target flow that the flow meter should be reading , if the target flow was 12 pounds and the actual flow was 2 pounds you got a fault code for low EGR flow. I believe the target and actual flow has to be within 10 pounds of each other of you got the fault code . The target flow as
  20. The 4094 and 5246 codes seem to always come together. We had 3 of our truck go down in one day due to these same codes. Cold weather seems to make them happen more than the summer. Poor DEF quality, bad NOX sensors, DEF doser not spraying enough or in the worst case a bad SCR box due to coolant or oil contamination from a past EGR cooler or turbo failure. On your year model the regen temps should be around 625 T1 and 880 on the T2 . As long as the T3 is higher than T2 your probably ok. Main thing Is T2 being 880 or higher. . ( Newer common rail engines have much higher regen temps ). You will
  21. Some of our common rail engines are now over 200,000 miles and still trouble free ( all MP8) other than the fuel rail valve and pressure sensor, there are CBR bulletins on replacing them with upgrade parts and also replacing both under valve cover injector harnesses. However we still have issues with random things. Our biggest issues right now are the Mack inter wheel locks blowing apart . I wish we would order them with the inter-axle air power divider only. Also our Mack T-310 trans seem to really like to go back the dealership for hi/low synchro replacement every 18-24 months. Our last 3
  22. Last I heard they did discontinue the clutched air compressor but the on/off water pump is still an option and maybe standard now. Our 2018 and 2019 do not have the on/off water pump but our 2020.5 has it . Also our 2020.5 has the air governor in the air compressor. Back in the ASET days we had a fleet of CXN tanker trucks with the same air drier/air governor set up. Our 2020.5 trucks also have 2 oil filters instead of 3 and also no fuel return line coming off the head. They did away with the electric fuel pressure valve on the fuel rail . This was a common issue as all our common rail engine
  23. I actually had a manual for the 5, 6 and 9 speed RVI transmissions in my tool box . All it says is “ Gear Oil. MIL-L-2104D or MIL-L-2104C. SAE 40 weight “
  24. My parts buddy back at the dealership couldn’t find much info on it . RS686LST built 2-14-79. ENDT676 engine with no mention of HP rating. TRXL 107 trans . 4.17 Mack rears. Could not get any real info on front or rear suspension. However it did have the optional ABS brakes .
  25. RH Sheppard has all their manuals on the website. I use it a lot . TRW used to have their manuals online but haven’t checked it a while. First thing would be to figure out which brand then which model gear box you have .
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