2007-2011 Macks

[Nightspear]

My brother-in-law runs a Sanitation business and has the opertunity to upgrade his 1992 International to a 2012 Mack GU713 quad axel with a 405HP MP7 and 10 speed transmition. However, the Guy that built his International advised him to stear clear of the 2007 - 2011 Macks due to something about their emissions (his exact words). Granted the Mack my brother-in-law is looking into is not in that range. He would still like to know what is wrong with 2007 - 2011 that he was recomended to stay away from them. Who would know better than the owners? So, I come to you to either disprove or confirm this recomendation. Any and all info will be greatly appericated. Thanks.

[ekennedy21]

It was mandated in November of 2007 that the emissions of diesel engines had to get a lot cleaner. The common solution was a particulate filter in the exhaust system that trapped pollution (particulates). As the filter clogged up, the trucks would run regeneration cycles to burn up this matter. This was accomplished by running a fuel line to a 7th injector in the filter assembly and burning up the particulates at a very high temperature. This would often require the truck to pull over off of the road an would take a good deal of time. This was all if the system worked correctly. There are many of cases where the truck is rendered dead on the side of the road or in safe mode(no power). In 2012 the newer more strict emissions standard came along forcing manufactures to abandon the diesel fueled injector in favor of burning urea to clean the filter. This system is in no means trouble free, but seems to have less bugs then the 2007 thru 2012 trucks. Also this wasn't a mack specific problem, it was industry wide(forced cat into a hiatus from the truck engine business)

[wheeler73]

2012 and up trucks still use a 7th injector to inject fuel for a regen. The SCR uses Urea injected into it to clean up the Nox. The 2007-2011 conventional cab trucks use a catalized dpf systems do have there issues which is usually a clogged 7th injector, air purge, and flex pipe issues. The 2007-2013 MRU and LEU use a non catalized dpf that have a lot of issues. The 2014 and up MRU and LEU use a catalized dpf and have very little issues.

[220cummins]

It was mandated in November of 2007 that the emissions of diesel engines had to get a lot cleaner. The common solution was a particulate filter in the exhaust system that trapped pollution (particulates). As the filter clogged up, the trucks would run regeneration cycles to burn up this matter. This was accomplished by running a fuel line to a 7th injector in the filter assembly and burning up the particulates at a very high temperature. This would often require the truck to pull over off of the road an would take a good deal of time. This was all if the system worked correctly. There are many of cases where the truck is rendered dead on the side of the road or in safe mode(no power). In 2012 the newer more strict emissions standard came along forcing manufactures to abandon the diesel fueled injector in favor of burning urea to clean the filter. This system is in no means trouble free, but seems to have less bugs then the 2007 thru 2012 trucks. Also this wasn't a mack specific problem, it was industry wide(forced cat into a hiatus from the truck engine business)

The 7th injector hasn't been replaced. It still places fuel in the exhaust to regen the dpf. The SCR aftertreatment is downstream from the DPF lower the NOx emissions even more.

http://volvoscr.com/default.aspx?pageid=3362

[turckster]

The 2007 emission models (2007 to 2009) was the introduction of the dpf system (Diesel Particulate Filter). The 2010 emission models was the introduction of the SCR system (Selective Catalytic Reduction) with Diesel Exhaust Fluid (DEF). The 2007 emission engines had issues with injectors and cups but those issues seem to have been remedied with the stainless steel conical injector cups and conical injectors. The 2010 emission engines had problems with injectors as well but it was because of a coating used on the injector needle valve. Most of the injectors with that issue have been replaced by now. Your friend may have been thinking about or referring to the double idler gear failures. I think, but not sure, that problem had been solved for engines manufactured after 2012.

All engines from both 2007 and 2010 emissions perform regens, catalyzed or non catalyzed. The purpose of the SCR system is to lower NOx (Nitrogen Oxide)

[kscarbel2]

I couldn't recommend a Mack brand (Volvo) engine until they finally fit them with common rail fuel injection, because of the ongoing injector cup issues.

And I wouldn't operate a current engine with the (Delphi) unit injectors, unless the truck was under warranty.

Tax cheating Delphi is all about cheap. When it comes to fuel injection, the heart of the engine, you don't fool around.......you go with Bosch (or the captive Scania-Cummins HPI or XPI).

On a side note, it appears Volvo is no longer putting downloadable PDF engine spec sheets on the Mack brand website.

(2013 example: http://www.quincymacksales.com/assets/Uploads/Documents/6-MP7-395C.pdf)

I suppose Volvo simply wants you to take their word. http://www.macktrucks.com/powertrain-and-suspensions/engines/mp7/

[Nightspear]

Wow! You guys are fast and informative! I didn't really think the emissions problem was exclusive to Mack, but I has to go on the info I had at hand,

This would often require the truck to pull over off of the road an would take a good deal of time. This was all if the system worked correctly. There are many of cases where the truck is rendered dead on the side of the road or in safe mode(no power).

I am not a trucker by trade, but is this part of the reason they enforce down time for truckers?

The 2007-2011 conventional cab trucks use a catalized dpf systems do have there issues which is usually a clogged 7th injector, air purge, and flex pipe issues.

Are these good places to start troubleshooting when a problem arises?

[Nightspear]

The 2007 emission engines had issues with injectors and cups but those issues seem to have been remedied with the stainless steel conical injector cups and conical injectors. The 2010 emission engines had problems with injectors as well but it was because of a coating used on the injector needle valve. Most of the injectors with that issue have been replaced by now. Your friend may have been thinking about or referring to the double idler gear failures. I think, but not sure, that problem had been solved for engines manufactured after 2012.

I will verify these have been fixed.

On a side note, it appears Volvo is no longer putting downloadable PDF engine spec sheets on the Mack brand website.

(2013 example: http://www.quincymacksales.com/assets/Uploads/Documents/6-MP7-395C.pdf)

I suppose Volvo simply wants you to take their word. http://www.macktrucks.com/powertrain-and-suspensions/engines/mp7/

I don't like to take manufacturers by their word, that's why I came to you owners for info. That way it the info is based on experience and not pushing a sale.

[ekennedy21]

no, downtime is not enforced for time for the def system to regenerate, that is strictly for safety. Regens are not really a scheduled thing. You would not or could not get the truck to run a cycle manually unless you had a mack service computer. Depending on different variables i.e driver habits, terrain, size of load, system working properly could go quite a while without running a cycle. It is one of those things though that the light comes on on the dash and you have to do it though.