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Q & A

What is Tier 4?

Tier 4 refers to a specifically defined level of federally mandated air-quality emissions standards established by the U.S. Environmental Protection Agency (EPA) that apply to new diesel engines used in off-road equipment. Essentially, the Tier 4 standard requires engine manufacturers to reduce the levels of particulate matter and oxides of nitrogen (NOx) to a level that is 50-96 percent lower than existing diesel engines. Any company that integrates engines into other off-road equipment solutions (e.g. large area rotary and reel mowers) must also integrate new Tier 4 compliant engine technologies into their products.

How did the tiered system come about?

In the mid 1990’s, the EPA outlined a “tiered” series of emissions regulations governing new off-road engines and equipment – culminating at Tier 4. These standards establish progressively lower allowable emissions of nitrogen oxides and particulate matter. It is a complex system and compliance dates are based on the size of engine (in hp and /kW-hr) and other factors. On the road to clean air, you might think of “Tier “0” as the starting line - where the diesel engine has basically no modern emission controls whatsoever, and Tier 4 as the finish line - where the diesel engine performing the same job will nearly eliminate particulate matter and nitrogen oxide emissions from the exhaust.

Which Products from Toro are impacted by Tier 4?

The general answer is that any diesel powered product with 25 horsepower and larger engines will be impacted in some way. Nearly all of these products are in our Reelmaster and Groundsmaster Product Lines. A list of each model that meets the above criteria is shown below.

Groundsmaster Rotary Mower Models

  • GM 3500 (33HP)
  • GM 3505 (33HP)
  • GM 7210 (33HP)
  • GM 4300 (44HP)
  • GM 360-2 WD (36HP)
  • GM 360-4 WD (36HP)
  • GM 360-4 WD w/cab (36HP)
  • GM 4000 (56HP)
  • GM 4010 (56 HP)
  • GM 4100 (56HP)
  • GM 4110 (56 HP)
  • GM 4500 (56HP)
  • GM 4700 (56HP)
  • GM 5900 (99HP)
  • GM 5910 (99HP)

Reelmaster Reel Mower Models
  • RM 5410 (36HP)
  • RM 5510 (36HP)
  • RM 5610 (44HP)
  • RM 7000 (49HP)

Multi Pro Model
  • MP 5800 (36HP)

How much more will a Tier 4 solution cost?

Manufacturers, like Toro, have partnered with Engine Manufacturers to develop Tier 4 compliant solutions for the Turf Industry. Due to significant redesigns and reengineering, all manufacturers’ prices will increase roughly 15%. Research in other industries that have been required to introduce Tier 4 compliant solutions in the past (such as Semi-Trailer Trucks, Agricultural and Construction Equipment, Compact Loaders, etc.) shows that it was not uncommon for prices to increase by 10% to 18%.

What are the advantages and/or disadvantages of purchasing Tier 4 compliant equipment vs. a non-Tier 4 conforming unit?

Environmentally, the new Tier 4 engines will be cleaner for the environment. Economically these new machines will have significantly higher acquisition costs. In short, a Tier 4 purchase is better for the environment and better for the long-term health of our communities. If you want to continue to use diesel powered equipment and be “green”, then Tier 4 machines are right for you. The disadvantage is that the cost of Tier 4 compliant equipment is much higher than Tier 3 or below.

Do Tier 4 Engines require special Diesel Fuel?

Yes. New Tier 4 generation engines and equipment are required the use of ultra-low sulfur diesel fuel(ULSD) which has no more than 15 parts per million (ppm) sulfur. ULSD fuel has been used since 2006 in on-highway vehicles and is now widely available. (For more information on clean diesel fuel requirements visit www.clean-diesel.org)

Do Tier 4 Engines require any special maintenance?

Tier 4 engines using a diesel particulate filter (DPF) do need to be removed and reconditioned (cleaned) at an authorized service center at approximately 3000 to 5000 hours. No other special maintenance is required. Normal maintenance intervals for oil and filter changes may be extended compared to today’s engines.

Now that the Tier 4 Compliant Turf Equipment is on the market, can I still purchase a Tier 3 machine – presumably at a lower price?

According to federal law and EPA regulations, manufacturers are encouraged to produce Tier 4 compliant only solutions for U.S. customers now that the Tier 4 regulation is in effect. The law does include some flexibility to ease the transition, but eventually – all Turf Equipment with Diesel powered engines of 25 horsepower and above must comply!

With that said, equipment distributors can continue to sell inventories of equipment from the previous generation technology (Tier 3) until the inventory is depleted.

Each Turf Equipment manufacturer may have different technology and unique transition plans, so it will be important for you to understand these requirements and ask your distributor about their specific plans.

Machines slated for export outside the U.S. are not required to meet EPA mandated emission standards (i.e. Tier 4). Manufacturers, therefore, have the ability to continue selling existing models or to offer alternative solutions in countries not under EPA jurisdiction. With that said, other Countries such as Canada and Japan are enacting similar legislation that will require Tier 4 equivalent products be sold in their countries.

How will the EPA Tier 4 mandate impact Diesel powered products currently in my fleet? In other words, are the products I currently own “compliant”?

Existing equipment that you own is “grandfathered in” and does not need to be replaced until the normal end-of-life cycle. The Tier 4 requirements apply only to NEW engines — including those sold in California and all other states. There is no federal requirement to upgrade any existing engine to the new Tier 4 standards. California is pursuing separate state law requirements for the modernizing and upgrading of off-road machines and equipment in that state. (For more information see www.arb.ca.gov/diesel).

What about Diesel Powered products less than 25 horsepower?

Products with engines rated below 25 horsepower are already Tier 4 compliant.

If I use 100% Biofuel, (i.e. B100) in my existing diesel equipment, will I be Tier 4 compliant from an emissions standpoint?

Yes. Biodiesel is registered as a fuel and fuel additive with the Environmental Protection Agency (EPA) and meets clean diesel standards established by the California Air Resources Board (CARB). Neat (100 percent) biodiesel has been designated as an alternative fuel by the Department of Energy (DOE) and the US Department of Transportation (DOT).

Will I be able to use bio-fuels in a new Tier 4 compliant engine?

Biodiesel blends alter combustion and exhaust temperatures and may impact the performance or durability of some new emissions control technologies when used in a Tier 4 engine. Equipment owners are advised to check carefully with their OEMs regarding permitted fuels or fuel blends and their use in Tier 4 equipment.

Can I retrofit an existing model to make it Tier 4 compliant?

No, due to the necessity for complex retooling and multiple modifications, we do not offer a solution to “retrofit” a current product to a compliant Tier 4 product.

How is Tier 4 Compliant Turf Equipment different?

The new Tier 4 Compliant solutions have:

  1. all new engine and exhaust systems
  2. more sophisticated electronic controls
  3. additional – after-treatment for removal of NOx and Particulate Matter
  4. redesigned frames and engine compartments to accommodate physically larger engine/exhaust system modules
  5. updated cooling systems.
The areas above represent the major areas where changes are required to meet the Tier 4 emission reduction mandate, but it is by no means an exhaustive list.
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