wheeler73

FELICELLO122 I will need the vin to see where you are at. It is possible but I am not 100% sure.

Hey Waterwagon you are at step 12A. Your dealer should be able to do 12B programming. Also have them check for any updated EECU software and data files.

Sure Waterwagon.

Is it at a dealer? If it is a month is too long. If not whoever is doing the repair needs proper training and the right equipment to do the repair!!!

Make sure the crank sensor connector is not connected to the EGR pigtail as they are the same.

You are at Step 9B. The dealer will need to call Mack tech support and have them turn it on. Also they can have tech support check if there are any updates to the EECU. If they won't I can have it done but your local dealer will have to do the programming.

I will let you know.

It is not a big deal to recalibrate. The trans set up is actually very sturdy. We have not seen many issues. The companies and drivers love the trans and the clutches are lasting longer than a manual trans.

The the trans need to be recalibrated as the clutch position has changed with a new clutch.

Sounds like your dealer does not know how to check the programming. I still do the 12B programming from time to time as we see less of the E-Tech and ASET engines. If you can give me the last 6 of the vin and if it is a CV or a CT model I can let you know. It may take me a day or two.

I use molycoat as it lubes them and then makes them swel to seal better. That is what Mack wanted to be ued when the MP's came out and I still use it with no issues.

The dealer can check to see if the truck has step 12B programming upgrade. If not they can have it turned on and reflash and reprogram and they can check if the engine module has any updates also. The 12B programming does help with acceleration power. Also check boost and fuel pressure.

The high speed data link is not seperate it is in the harness. What year is the truck and which part of the harness are you pulling on?

Has there been any work done on the trans recently? This is not common. I would recommend a reman trans as there is also gear damage done. The reman overall is a better way to go with a good warranty.

Also in the top center under the CB mount. There are 3 T27 screws holding the cover down. The cover is triangular.

What year is it. How high does it go to and is there any throttle response?

The supply pump could be the problem. You will need to remove it to see of the gear is spinning on the shaft. That is a common issue. I would check the fuel pressure first. Also the restrictive fitting (check valve) can be bad. If the pump is bad I always replace the restrictive fitting at the same time.

Have the steering gear u-joints been replaced. If so the steering shaft could be out of faze.

I have not seen it yet but heard it is connecting rod failure.

The 5-8 and 5-9 codes are most likely a bad mass flow tube which is common. It comes as a calibrated assembly with a module that bolts behind the EECU. Is the fan clutch staying engaged at all times as this will cause a power loss also.

They are CHU and CXU with the MP engines. The frames were redesigned a little from the CH and CX to the CHN and CXN.

Could be a high pressure fan switch for the A/C stuck on. Is the malfunction light on?

Could be a high pressure fan switch for the A/C stuck on. Is the malfunction light on?

Its about 6-7 hours depending on the model of truck at your dealers rate plus parts.

It could but you could have other issues also. The boost pressure sensor reading incorrectly will cause your symptoms and not throw a code.