TIER 4: BIG CHALLENGES FOR SMALL EQUIPMENT Tier 4 has compact equipment manufacturers searching for the right place to stick aftertreatment systems
BY DAWN M. GESKE As the off-highway world deals with the onset of Tier 4 emis- sions regulations coming into play — depending on the horsepower range — from 2011 until 2015, it is not surprising that the smallest equipment faces perhaps the biggest engineering hurdles. The small size of machines such as skid-steer loaders (SSLs), compact track loaders (CTLs), mini excavators and compact wheel loaders, and the limited space of their engine compartments, has engineers working overtime to keep engine package sizes down, while at the same time accom- modating larger cooling systems, added weight and the pesky task of fig- uring out where to mount the aftertreat- ment as they reach Tier 4 final. Most equipment manufacturers have
