Rockwell

Really sorry to hear of your troubles Keffer, just a real shame. Ya go out and buy a rig to provide for your family and have this happen. Im in the same boat as you, big piece of me regrets buying this truck. Nothing but reliability issues, to much money spent on emissions garbage, and most repairs have you locked into Mack doing them. Like you, for the moment im stuck with it. Mine has 540,000 miles on it and i still owe to much to sell it. Far to much complexity in these trucks. Its got me walking in fear everyday of the next multi-thousand dollar repair. Its as if they are "built to break". I have near zero confidence that this truck will live long enough to either sell or be payment free. Always 1 mile away from disaster. I've been trucking since 1989, and if any truck can take me out, this is the one. I hope your troubles pass quickly and with good resolve.

The 7th injector r/r = $1254.62 Now here`s where I really got stupid... When I dropped the truck off, i knew I had a leaking wheel seal so I said go ahead and fix that to...well turns out I had 2 leaking wheel seals. No worries, $650.72 bananas later, fixed. And even greater stupidity.... I tell the shop manager (this is before any diagnosis) "Since you're going to be in the computer poking around anyway, can I get a few parameters changed?" ..."Sure!, what ya need?". Now at this point i'm assuming they just do this free as a courtesy, ya know they are in there anyway right, change a 1 to a 0, a 0 to a 1 in the settings...no big deal, and ya know Mack is so understanding of us working guys. Well... Change max road speed to 80mph = $70.00 Allow idle ramp up using cruise controls = $210 Remove fuel bonus/penalty function = $000 I got this one FREE! And wait! My stupidity doesn't end there... "Hey, ya know what, while ya have it, charge the AC. It works fine but just isnt super cold"..."Sure thing! You got it!" Charge AC = $331.80 (yes, charge only, no repair to AC) My grand total, $2,711.71 and ONE FULL WEEK in the shop. Yup, I dropped it off on a Friday, and I never got it back until the following Friday. And on SO MANY levels, I have only myself to blame, beginning with the purchase of a truck later than the year 2000.

Thank you Stack, this was a double post. Please ignore this thread as this is a duplicate. My bad. Sorry

Truck still in shop. Anyway, this is copy and pasted from repair estimate provided to me by Mack... CHECK ENGINE LIGHT IS ON - CHECK & ADVISE - NEED ESTIMATES Parts: (1.0) INJECTOR (21089234) Complaint: CHECK ENGINE LIGHT IS ON - Cause: HOOK UP LAP TOP TO CHECK CODES. SPN3556FMI4 ACTIVE FOR 7TH INJECTOR CIRCUIT FAULT. PERFORM GD CIRCUIT CHECKS TO FIND HIGH RESISTANCE IN 7TH INJECTOR CONTROL CIRCUIT. ADVISE TO REPLACE 7TH INJECTOR Correction: NEED TO REPLACE 7TH INJECTOR I gotta tell ya, I like a clean environment as much as the next guy, but emissions stuff is ridiculous. You wont choke to death breathing the air, but you'll financially choke to death paying for it! My next truck is gonna be so old, the Smithsonian will be jealous! Wanna go back to the good ole days of trucks.

Awesome! Thank you.

Linxup. Cheap, easy install, reliable, does ifta for you as well. Been using it for years although that may change with the ELD mandate.

Thank you very much Keffer , Inc! I have the truck in Mack now, I was afraid to keep running it, although it was running just fine. I'll post the outcome to hopefully help others down the line. That's good info that you've experienced other codes that clear on their own. I tend to panic when I get a MIL light as I'm fearful imminent shut down or derate will soon follow. Don't like computers in trucks!

Check engine light came on, truck running fine, all gauges are great. What is this code? Can I run? 2011 MP8 445 SA 0 SPN 3556 FMI 4 Cant seem to find it online, any help is greatly appreciated

Check engine light came on, truck running fine, all gages are great. What is this code? Can I run? 2011 MP8 445 SA 0 SPN 3556 FMI 4 Cant seem to find it online, any help is greatly appreciated

Just a friendly update to this topics in hopes it might help another down the road. It happened again, same scenario, long, hard pull with a heavy load. Just about to the top of the grade and my check engine light appears. Same code as before... SA: 0 SPN: 4752 FMI: 7 So, after some online research, and rather than take it to Mack again, I decided to butt heads with the computer myself. I replaced the Venturi tube and Differential Pressure Sensor and that did the trick! Its a simple, easy to do fix. Depending on your year engine, Mack (Volvo) has updated the Venturi tube and Sensor. You will need a new mounting bracket as well as a new jumper harness for the sensor. End of the day, just shy of $500 total in parts. Immediately after replacement, the code became inactive and MIL went off. Now I might have been able to just try and clean the sensor and tube, but once I had it all out , ahhh, just replace it. If you want to try and just replace the sensor only, you might find you are forced into buying a new tube, bracket and harness as the updated sensor will not fit on the old style Venturi Tube. As a side note, There's just something not right about getting your Mack Truck parts in a Volvo box!

I appreciate the explanation 41chevy, that does put it into better context for me. I guess then theoretically, as you continue to update the software, it becomes better refined and more accepting of wider ranges of operating possibilities. Still seems funny to me though. In the past, Ive never had to amend or update my truck to do what it was built to do, pull the load. Its kind of like amending a pool to hold water! (Here`s your pool, in the future however you may need to re-teach it that it has to actually hold the water, cause it might forget its purpose) I'm not knocking it either, just forcibly trying to move on with the "modern" times lol. Thanks again!

Well, a day of lost revenue and a $480.73 charge from Mack and my problem is supposedly resolved. Macktech689 hit the nail on the head. Software Reprogram. I dunno, help me to understand, how does software go bad? I mean, the truck ran fine for months on the software as it was, why does it just up and decide that now all of a sudden the software is no good? I just don't get it, and I guess because of that, I have very little faith in the repair. Half a grand and not one new part? just a bunch of code. I guess the bright side is, it was only $480. and they did get it in/out the same day! But I just don't get it! LOL

Thank you for the terrific replies. Its very much appreciated when a guy has few places to turn for insight. I finally caved and decided to drop out on my work for today and take it to Mack. One day`s revenue (hopefully it only be one day) isn't worth possible damage to the motor. I was going to start ripping apart the Delta P sensor and Venturi pipe myself to maybe try and clean but then came to the realization i`m out of my territory with all this emissions stuff. I will post back what Mack finds, hopefully that will help the next person down the line. Thanks again !

Well, here we go, not even 20K miles in on my recently purchased used 2011Mack with an MP8 (505,000 miles) and I get my first check engine light. SA: 0 SPN: 4752 FMI: 7 Topped a long grade with a heavy load, check engine light comes on. All gauges read normal so I kept on truckin to get my load delivered. Truck is running fine and brought me back home. Code seems to reflect EGR or EGR cooler related issue. My question is? Can I run this until I can conveniently schedule it into the dealer? Or am I looking at my first downtime with my MP8? I have lots of work lined up that would really hurt to lose . I also don't want to risk damage to the motor or having it go into derate mode and basically stranding me. I do NOT like these "modern" motors...not one bit. Thank you

Yeah, I know, I know, it would have to be a very long cable! 2011 Mack CNX613. On the interior right side wall of sleeper there is a cable hookup. A threaded shaft with hole in the center exactly as you would find on the back of any TV. What is this for? Where does it go? There`s no exterior antenna on the rig. I do know this truck used to have a qualcomm system in it, possibly was something for that? Any ideas? Thanks!

I have this identical truck, except my rears are 3:25. As WiserfromBud states, it does strain a bit pulling heavy going up grades, but it gets it done. Makes for great fuel economy on the flats, but you blow it all in on the grades lol. I would rather a taller set of rears, but hey, it is what it is. Very generally speaking, I shift at 1800 and it drops back to about 1200. Cruises at 65mph @ 1450rpm

Firstly, THANK YOU ALL for the help and response! I hadn't noticed this while on the side of the road but I now see this truck has a Steering Damper on it. I guess that's due to the air ride axle. I'm most likely going to change that out for a new one at some point if it occurs again. Hopefully I just hit the "mothership" of all potholes and it was a one time event. I did learn I have the Hendrickson Airtek system. For anyone else that might have the same, Hendrickson has lots of info on their site including diagrams and part numbers for specific makes/models of trucks.

Thanks for all the Welcomes! I just knew there had to be another Dog from NJ here! I'm in North Jersey (extreme NNJ, think High Point) Ill start a gallery when I have some time, Ive got tons of pictures of our old trucks and Dad! The very first truck I ever owned was a 1979 GMC General with a Silver 92 V8 @ 445hp. Yeah I know, its a Jimmy and I probably shouldn't brag to much but back then I was so proud I got that rig tattooed on my arm! (minus the oil puddles) Dumb kid!

I don't know if there are beads inside or not as I just purchased truck. Ya think a weak shock could be the culprit? Not a completely blown shock, just weak? Maybe that would explain why the truck rides fine all of the time and this one big hit sent the front wheel into an up/down motion that the front shock could not resist? Could the shock be strong enough to handle normal abuse, but weak enough to not withstand a larger impact? Possible? Other than beads (which is a great thought) this is the only theory I can come up with. If it happened once, I have to assume it will again and I don't look forward to it.

Hello All, Just thought I would take a moment to properly introduce myself to the collective forum. Name is Jim, I hail from New Jersey. Been in the trucking industry since 1989 when both my father and I started our small trucking company. I've always been truckin crazy (pun intended), always wanted to be in them or around them as far back as I can remember. My Father and Grandfather spent their entire lives pushing rigs across the nation and by the looks of it, so too, shall I. I`ve owned a few Macks over the years, mainly R-Models and U-Models but have driven others. Always a great, tough and dependable truck, every one of em. I honestly can`t say I'm ultra loyal to any specific brand. With the exception of a few, I like em all. We ask some demanding chores from our rigs, in the end, if they hold up and get the job done, and do it time after time, that's a good truck. That's the short of it. I look forward to reviewing the wealth on info within this forum and sharing what knowledge I can. Regards!

Thomas, No centramatic or similar is being used. Now I cant say for certain if balancing beads are inside the tire, thats possible. Very good thought! Eddeere, No ABS light. No warning lights whatsoever. Thanks!

Hello, So im cruising down the interstate in my new (new to me) 2011 Pinnacle (230 WB w/sleeper) and 53' dry van empty. Im running about 68mph when I see 2 potholes ahead of me, one to the left, one to the right. With limited time, I offset the rigs path to avoid the left pothole, but wind up clipping the other pothole with my right front runner. BAM! I feel the inital and thunderous pound of the pothole, then, the whole rig begins to shake, vibrate, and shutter with alarming force as if Im loosing my front runner. I immediatley let off the throttle, and apply no brakes. As my speed naturally decreases I put the flashers on and begin to bail for the shoulder. 60 mph, 50, 40, 30, and then at about 20mph the rig stabilizes. I complete the stop, get out and check everything. All looks fine, nice and tight. I merge back onto the intserstate and all is well. As I gain confidence, I bring the rig back up to about 70mph. The rest of the day it rides smooth as silk. No vibrations and no problems going over bumps, seams, steel plates, or ruts. What could this be? Bad or weak shock? The truck does have an air ride steer axle. I have no experience with air ride steer axle setups. Having purchased this truck very recently, the chassis was freshly painted by the dealer so its tough to see the "true" condition of things like the shocks. Any ideas? FYI, the interstate I speak of is I-80 in New Jersey, need I say more.

Hello All, Im a new member and posting to this forum for some desperately needed feedback. I have a hold deposit down (with Arrow Truck Sales) on a 2011 Mack CXN613 with an MP8-445, with 488K miles, and all the emission controls that come with it. The truck is very clean and fleet maintained with only one owner. Originally I was very excited, this excitement has turned to fear. A huge fear of the DPF system, SCR, sensors, EGR, 7th injector and the motor itself. Im an old dog, the last Mack trucks I owned were R and U models. Currently I have all pre emissions Cummins and Detroits in my trucks (non-Mack). How is this year (2011) MP8 for longevity? How is the MP8 and Mack in general with all these emissions and sensors. I hear so many horror stories about emmissions controls rendering trucks useless and spending more time in the shop than on the road. Like many, Im a small guy and fearful of buying a nightmare that will ruin me. I also realize, short of buying a glider kit or restoration (neither of which I can afford), I have to move with the times, or at least try. I greatly appreciate any input you might offer. Full Specs: 2011 Mack CXN613 MP8-445 Fuller 10 speed Rears Ratio 325 Thank you!