96bulldogpower

736GB421M3X courtesy of Mackpro, he helped me out with this in the past. Hope this helps

injectors.pdf

Hey guys I have a CHN with Mack rears that snapped a thru shaft last week on the front/rear. I had spare parts at the shop so I waited till I had time to pull them and just got around to installing today. It seemed pretty simple, the shaft snapped and it pushed the half with the yoke straight out of the aluminum seal flange. After replacing the broken parts I turned the output yoke by hand and it spun the front yoke as expected. Unfortunately every so often if I’d spin it faster, it would feel as if something inside would slip as if a spline was stripped or something. I put everything back together and with the power divider unlocked, the truck would spin the rear tires even with the brakes at near full pressure, so it leads me to believe it’s okay? Am I missing something? Would the auto power divider make it behave that way when spinning it by hand?

Hey guys! I was hoping someone here had access to part numbers for the chrome mirror covers with lights built in. About 6 years ago I bought a set from an online auction but I can’t seem to find updated part numbers on these so I can get them again for a new truck I’m putting together. I only have what I believe to be the outdated part numbers for the left side: (8413-97429) and (23914107). Can anyone here share the left and right side updated part numbers? What a ballpark price on these nowadays? much appreciated!

Guys, just wanted to post a follow up on this. The truck has been back to work for going on three weeks now. It’s had a 300 mile trip in addition to all the daily on-site hours it has logged, and the oil level still hasn’t risen. I’d call this a fix!! I’d also like to add that we’ve noticed and improvement in fuel economy as well. I’d like to thank you guys, especially Heinz for the help!

Alright guys, I went ahead and installed new cups and injectors. The truck now sounds a little quieter and isn’t quite as strong as before. It’s not slow by any means and I believe it pulls about as strong as our other trucks, but there was a noticeable power decrease right after the injectors. My theory is that maybe the injectors it had on before were off a d13 with larger nozzles? I have no idea, but I’m happy with the results. I will be giving an update in a couple of weeks when the truck works for a bit and let y’all know if this healed the oil level rising problem.

Oh man 😓. You’re a lifesaver! I just went ahead and placed my order on a six pack using the p/n you provided. It ships out today, I’ll get them installed as soon as they arrive and I’ll keep you guys updated on the results after a while of working the truck

Would this cause the truck to be horrendous on fuel economy? We have a mix of 18 speeds and Allison’s. We’ve always known our Allison trucks to be bad on fuel economy but this one seems to be the worst, and this one is also an Allison truck.

Currently the engine has all Volvo injectors with part number 22479123, I figured these were original to the truck? Would the six pack part number you referenced interchange with the ones I currently have? Vin: 1M2AX04C5CM011802

Okay guys, update this morning I’ve exhausted all my UV dye, I’ve never used this much dye trying to find a leak. I’ve checked meticulously around each and every injector, plunger, and both gallery plugs. I still cannot pinpoint a leak. I have a suspicion of a faint uv glow from the injector plunger springs but I’m not sure it’s even that, at this point even the oil pooled up on the head seems to glow 🤣 it’s driving me crazy.. I could be wrong, but I don’t suspect cups just because the engine starts and runs perfectly with no performance issues, no air blowing into the fuel system either.

The truck has about 280k miles and about 20k hours. It’s got the original injectors as far as I can tell

I’ve got a feeling you’re right about that. After inspecting it further tonight I can the the FAINTEST uv dye glow on the injector springs. I will look for new injectors at this point, looks like this is probably my best bet.

It’s for sure fuel, I haven’t got an oil sample yet (going to send some off though) but I’m certain it’s fuel. Put a drop on cardboard and it leaches out. Smells like fuel too.

No other concerns besides the rising oil unfortunately 😞. Truck starts and runs great. No misfires or smoke. I’d hate to throw parts at it and I don’t have much time to work on it before it has to go back into service in a week and a half. If I can’t find anything else tomorrow then I may just have to put it back together and order a set of injectors to throw at it next time it come back to the shop and hope it fixes it. Meanwhile we’re changing the oil once a month

Do you mean the fuel pump that mounts behind the power steering pump? I thought about that but fuel isn’t mixing with the power steering fluid, which I assumed was the first thing that would happen if the fuel pump seal went out.

hey guys looking for some help on this one. I’ve got a 12’ Mack granite with an mp7 that’s making oil. Oil level rises about a gallon every two weeks. I’ve put UV dye in the filter and checked to see if I could find the leak, I found nothing around the injectors or galley plugs. I then added another ounce of dye directly into the fuel gallery through one of the plugs and still nothing. I can’t find the leak even after hours of looking. Anyone have any ideas on where else these engines can pass fuel into the crankcase?

My understanding is that anything 44k and over has the transverse rod. Just based on what little I’ve gathered, it seems that the only difference between a 44k and a 46k is that the 46k will have cast iron axle housings, whereas the 44k has stamped steel housings. I’d like to be able to know for sure though.

As the title reads, I’ve been around Macks from the 90’s up. One thing I’ve never really understood are the differences between 44k and 46k camelback suspensions. Does anyone know what it would take to upgrade a 44k to 46k? A local guy has what he claims to be a 46k cutoff but it appears to have the same leaf count and size as my current 44k setup.

Sorry guys I’ve been absent from the site for a while, just wanted to follow up on my findings. a little background on the truck, we bought the truck originally inop from auction. Found it to have a bad PCM so we replaced it and the truck ran great. Fast forward a couple of months into service and we had this issue happen. The truck could never complete a regen. We eventually got the truck back to our shop where we could properly diagnose it. We removed the dpf to inspect it and found our problem, it had been hollowed out, the old pcm was deleted and we had no clue. We replaced all emissions components and reset parameters on PTT and life has been good since. Just figured this info could help someone in the future, if your truck never finishes its regens and all else looks good, take a look physically into your dpf.

Hey guys looking for help again on this one. Dealing with a 2012 granite with the mp7. The problem started when the dash requested a regen “SOON”. I tried to regen the truck with the dash switch and it would only raise the idle and drop after 3 seconds. I hooked it up to PTT and discovered spn3675 fmi7 for a fault on the turbo bypass valve. I diagnosed a faulty valve, replaced it and verified its function then it allowed me to properly start a regen. When it first started a regen the truck blew HEAVY gray smoke for a while, the regen lasted just over an hour when it was interrupted by the low fuel light. I quit that day and tried again today, filled the truck with fuel and tried another regen. Now the dash says regen “REQUIRED” I allowed it to regen and it lasted over 2.5 hours with no signs of stopping, I stopped the regen because I had to be out of the yard by a certain time. No codes are present, egt’s while regening are around 750° at their highest, differential pressure has now dropped to about .03-.06 but it still blows a little gray smoke while it’s in regen, on jpro it says soot level is at 48% and I can’t get it to drop, also truck is in low derate. I’m not sure how to proceed, anyone have any tips on what to do or check? I’ll attach a pic of my jpro screen.

I’d sure appreciate any info or schematics! I haven’t had time to dig further into it, but any info would help a lot! I am also suspecting power/ground problems but have no real way of getting diagrams for this truck. I did find some corrosion at the plugs on the epdm by the driver side kick panel/firewall inside the cab, I cleaned the plugs but it made no difference.

Did you ever find the problem? just my experience with an 05’ CHN AC engine/allison auto… we had this truck that would overheat and push coolant out of anywhere it could, most times it would be from the reservoir cap until it got worse and started blowing out the plastic radiator end caps. We replaced two radiators before we got to really looking at the truck. We found that the egr cooler had cracked and caused exhaust gas to pressurize the cooling system. We replaced the egr cooler and further investigated the cause of overheating which cracked the cooler. We found that the big aluminum coolant plate where the water pump goes mounted to was eroded badly at the water pump impeller area. We ended up replacing the whole coolant plate and new water pump. Since the water pump couldn’t efficiently pump coolant because the plate was eroded, it caused a low coolant flow condition, it gradually worsened until the engine started overheating and cracked the egr cooler which then pressurized the cooling system and caused it to overflow. It’d be worth looking into if you haven’t already fixed it, we had no oil/water contamination. Sounds similar to your situation. If you remove the water pump look into the coolant plate and see the area where the water pump impeller sits, inspect for ridges or eroded material.

If you can get past the cam issues on these AC’s, they’re GREAT engines. This one in particular got larger injectors and home made egr delete. Since I can’t get tune files anymore from my dealer, I got a used 460p ecu and it was a major upgrade from the 380hp file it had. I never got it dyno’d but it makes impressive power!

It’s a love/hate relationship for me, when the mp’s work they work great! Until it’s time for repairs 😂 I have always loved the colors too, hence the color scheme on this one after rebuild