DoubleFrame

I ran a ground cable from the top of the ECM mounting bolt to the frame and she starts right up. I believe I found the broken cable on the engine ground below the starter. I’m getting ready to fix that now and just need to buy a bigger connector because there are like 5 cables to that ground connection. Thank you for your help.

Thanks Jojo just tried that but in my trouble shooting I have discovered that when I touch the ECM to the intake manifold I am able to start up the truck. It seems to be a ground cable that hours to the ecm. Not sure which one is it yet. Thanks 

Hey guys I hope to find some help here. I have a 2006 CV713 that is not starting. I have found that when I push down on the top harness plug on the ECM the truck starts right up. I’m trying to figure out which cable is bad, does anyone have a pin diagram for the ECM? The harness is on national back order! 

20 hours ago, Mark T said:

Don't suppose it could be something like the type of tires you use ????  They look pretty nice, doubt there's anything neglected on the trucks (worn suspensions) 

We use closed shoulder JKTyre JetSteel Indian drive tires at 120 psi. I’m going to put them at 110 psi and see if that helps. 

20 hours ago, The Rubber Duck 006 said:

Almost sounds to me like the power divider isn't engaging correctly. The dump truck I drove had a system on it that was better than the divider itself. It was almost like a Transfer case that was air activated and locked all axles together and allowed the truck to go through just about anything. I can't remember the name of it but it was a full locker system. 

I also have an automatic with a Hendrickson haulmax suspension that has lockers and I don’t have this issue with that one. 

20 hours ago, tjc transport said:

#1:  pusher axle MUST BE UP before going any way near sand of loose material. 

#2:  the more power, the more hop. use 2nd gear, NO THROTTLE, and feather the clutch.

#3: steering wheel straight!!!

I’ll try this out this week. 

On 10/15/2022 at 9:22 AM, Joey Mack said:

are you able to reach in by hand and move the box rubbers at the ends of the springs? if so, they are worn out.  also look and see if the 'twinkies' are in the boxes at the sides of the spring ends..  

can’t move them by hand, I had the camel back suspension redone a couple of years ago. Twinkies are good. 

6 minutes ago, Joey Mack said:

do you engage the power divider before you get on the sand, or after wheel hop starts? 

Power divider is engaged before 

13 hours ago, fjh said:

If you have rubber frame to diff torque rods try removing them for a day see if this helps! We had customers that said removing these made a world of difference traction wise on dump trucks ! That said Mack at one point offered sealed grease torque rods on certain models MR maybe that had few issues on garbage packers may be an alternative! ! Maybe give it a try! If you have two remove one or both to try it! the down fall being the suspension will dog track some on turns! 

Just something to try!

This is a common denominator, they all have the diff to frame torque rods on the Rear Rear. I’ll definitely try removing them on a couple of trucks.

15 hours ago, Swishy said:

Some things th@ might 

<1> Spread on tandem drive

<2> Too much weight on steers

<3> Tyre air pressure

<4> Try higher gear and cruise in on site

<5> Use lower gear with lotsa revs on site

<6> check tandem drive suspension for ease of osillation

<7> Parrallel tracking (look along the walls of tyres}

 

A pic of the beast could help

With thanx

cya

Thanks for the response, I’ll look at those details this weekend.

here are some pictures of the trucks

15 hours ago, Joey Mack said:

how many trucks do it?  are there other hired trucks that are doing the same thing?  Is it just because you are on sand?  empty or loaded, or either? jojo

All of my trucks do it, I don’t see many hired trucks with this issue. It’s worst when empty. 

I have several dump trucks (Granite E7 350/ EF 8LL/ 4.30 ratio/ Hendrickson suspension) and a couple of AI 400/ maxi torque T310/ 4.17 ratio/ camelback. I’m having trouble with my trucks getting stuck a lot, we are in Florida so the dirt here is sandy. When drivers go off road the trucks start bouncing as soon as it hits a soft spot and we watch other trucks go by without any issues. We have tried the mud and snow button (ATC) and the Off Road button, power divider. Tried driving in low gears, higher gears and the trucks still bounce like crazy like it’s trying to get traction but it can’t so all it does is hops until it gets traction again. I’ve asked drivers to just get pulled out by the dozer or loader as I’m afraid they will break something. I’m not sure what else to do so I’m coming on here to ask for your recommendations. What are we doing wrong? What can we do different to prevent the wheel hop or to get traction? Thanks 

Sounds like I’m having a similar problem. The truck starts and idles good but stumbles and hesitates on low RPMS. I just changed the exhaust manifold so I had to remove the injector tubes. I purged all of the lines before starting and then several times after thinking it could be air in the fuel system. Additionally I had to change the fuel priming pump because it started leaking. It’s been two days now, no codes yet. 

Just wondering if anyone can help me troubleshoot flash code 2-9 Combustion Air Humidity on a Mack AI engine. No other code. 

Does anyone know where can I find the service manual for the suspension? I have a 2006 Mack CT713. I think it’s the same suspension setup as a GU813. I need to replace the front springs? Thanks 

I had a 2008 GU with the same issue, it ended up being the injectors and injector cups. 

I was able to locate the issue last night. VECU Wires were rubbing against the kick plate. Thanks guys for the response. The truck worked fine today. I added a foam padding to prevent this from happening again. 

Hey guys I have an issue on one of my CT713 Ai 370hp. The truck has been having issues this whole week where it’s accelerating on its own. It doesn’t matter if it’s in gear or not it revs up randomly. Today it went all the way to 2200 rpms while entering a job site. I changed the throttle sensor a couple days ago and it didn’t help, same issue. I have the truck running at the yard and it’s acting like nothing is wrong. I’m checking wires now to make sure there isn’t a short somewhere. Any suggestions on what the issue could be? Thanks 

I found the document, it calls for a hub replacement. Which sucks but we don't have a choice!

PV776-89271728.pdf

Hello I had a front (steering) wheel bearing go out on my 06 CT713. I have never messed around with non oil lubricated bearings. I tried looking around for documents and I cant find any. Does any one know where I can get documents or are there any tips you can give me to replace these. much appreciated. Thank you.

Thanks guys for the response. It definitely gave me something to think about. I’ll post pictures if I end up getting it. 

I’m thinking about buying a CL with a E9 V8. I’ve never been around this motor. We have had E7 and Ai motors for over 20 years. What should I look for and should keep an eye on an E9?

Hi guys I have a 2007 CT713. The AC control panel keeps going out specifically the fan switch (rotary switch). It works great for about six months and then it starts going out. The switch looks like it’s burnt from the heat the cables are producing. Any idea how to troubleshoot? 

Thank you for the response.

Update- it ran fine for about 30 minutes. Oil pressure was at 30 psi on idle and 60 psi @1400 RPM. Suddenly the oil pressure dropped to 20 psi and then 0 psi and engine shut down again. So I'm back at where I started. 

Update- I got a code.. 1-1 oil pressure sensor fault. I'm going to change it out now. 

Help please, I just did a oil change as I normally do. I filled up my oil filters and all and then I cracked up the truck and noticed oil pressure dropping to zero on the gauge and immediately the Truck shuts down as I am in the cab. I noticed that my oil filters are extremely hot, I let the truck sit a little and changed the filters again... thinking that the filters may have been bad. Now I cranked the truck back up, everything seems to be running ok but still notice that the filters are really hot and oil pressure is at 25 psi. Which it would normally be around 50 psi in a cold start. What do you guys think this could be? 

Engine is a 2007 Mack Aset 427