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What Year Semi Trucks Are Pre Emission? (12 Important Facts)

We’re going to have a look at the importance of DEF, EGR, and DPF and why the government issued them in the first place as well as what they actually mean for us and the environment.

Pre emissions in some form or another have been around since the 70s but strict regulations came into play for pre-emission from 2007.

And year on year the EPA has introduced new tests and regulations.

Here’s a quick answer to what Year Semi Trucks are Pre Emission:

Semi trucks manufactured prior to the year 2002 are considered pre-emission as they were not mandated to have emission reduction technologies fitted. Stringent emissions regulations were imposed by the EPA between 2002 and 2010, forcing trucks to have technologies such as EGR, DPF, and DEF fitted.

What does Pre Emission Semi Truck really mean?

Pre emission semi trucks are trucks that are not fitted with emission reduction technology.

In 2007 low sulfur diesel fuel was introduced onto the market for heavy-duty diesel trucks which reduced the ppm from 500ppm to just 15ppm.

This was a huge improvement and one that set the bar much higher for engine manufacturers.

In 2010 huge changes took place with new engine designs that would reduce emissions further.

The U.S. Environmental Protection Agency (EPA) and California Air Resources Board (CARB) require confirmatory test certificates to be held and updated each year.

Any vehicle should have an engine 2010 or newer to comply with regulations, any older models will have to be upgraded to meet the standards implemented by the agencies.

By introducing pre-emissions the agencies have been successful in forcing manufacturers to re-design their engines thereby creating more cleaner emissions and reducing the NOx.

The agencies are continually working on further reducing emissions by monitoring workshops to ensure they are complying with the standard on a yearly basis.

Truck manufacturers are way ahead with the hybrid and even fully electric trucks and will pave the way to zero emissions even before it is required by law.

What are EGR, DPF and DEF with regards to semi-truck emissions?

Exhaust Gas Recirculation (EGR) is an important pollution reduction method.

The EGR valve regulates the mixture of exhaust gas and air.

As a result, less oxygen reaches the cylinders which will produce a lower combustion temperature, reducing nitrogen oxide by up to 70%.

Diesel Particulate Filter (DPF) is a very fine filter that catches soot and exhaust smoke to reduce them down to 1 micron which will further reduce emissions.

The Diesel Exhaust Fluid (DEF) works in conjunction with the (SCR) Selective Catalytic Reduction.

The DEF slowly releases ammonia into the SCR and combines with the NOx (Nitrogen Oxide) from the engine which creates a less harmful exhaust fume in the form of water and nitrogen.

All of these result in cleaner air and meet the standards set by the EPA in regards to semi-truck emissions.

When did Emissions Start on Semi Trucks?

Since 1974 the United States Environmental Protection Agency has been introducing heavy-duty engine emission regulations. and over the years have gotten stricter, with the next introduction in 1988.

Then there was a huge gap before the next standards were placed between 2007 – 2010 which caused a stir with engine manufacturers.

In January 2020 they released an Advance Notice Of Proposed Rulemaking (ANPRM) for a cleaner truck initiative to update HDV Nitrogen Oxide standards.

This has not been taken any further as yet, but we should expect new regulations to come into play in the next few years.

What is the Significance of Emissions on a Semi Truck?

Since the EPA ordered cleaner emissions in our semi trucks we have seen an increase in cleaner air with the reduction of pollution through regular tests.

Semi trucks produce cleaner emissions thanks to their EGR, DEF and DPF, smarter engineering, and designs.

This is important to not only us but our environment.

By reducing emissions we are technically reducing the global temperature also known as global warming.

This if not dealt with, will cause major issues for future generations.

This may not sound too alarming but mother nature may not be so kind as to warn us of what is coming, we have one planet and it is up to us all to look after it.

What Years did Semi Trucks get EGR?

EGR first made an appearance in 1972 but it wasn’t until October 2002 the EGR apparatus became mandated on heavy-duty diesel engines by the EPA.

It was regarded by the EPA as a great way to reduce NOx emissions.

Tests proved the effects the EGR had on the NOx reduction at different engine loads with mid-speed conditions.

As the EGR rate increased, the NOx decreased but showed an increase in heat.

This is why we waited 30 years for its re-release. The EGR combined with its cooler was something that designers and engineers needed time to consider.

When did they Start putting DPF on Semi Trucks?

The Diesel Particulate Filter was considered in the 70s but didn’t have its debut until 1980 when they were used in non-road machines and then introduced to cars in 1985.

In 1987 heavy-duty diesel engines had to be capped on their particulate emissions but this wasn’t enough.

However, in 2008 the California Air Resources Board (CARB) launched the California Statewide Truck and Bus Rule.

In order to reduce emissions by at least 85% they retrofitted engines with CARB-approved diesel particulate filters, the DPF.

What Year Semi Trucks Require DEF?

In 2010 to further reduce NOx and (PM) Particulate Matter in diesel engines, the EPA enforced all heavy-duty diesel engines to be fitted with a DEF.

By 2023 all vehicle models must have 2010 or newer engines.

The Californian governor is on a mission to have semi-trucks and passenger vehicles down to zero emissions by 2035.

With DEF readily available almost everywhere this shouldn’t be a difficult task.

California has a higher pollution level than any other state but with its rules for heavy-duty trucks being stricter than other states it has caused issues with federal officials and manufacturers who want one standard for all.

What Year Semi Trucks are Pre Emission?

Semi-trucks have always huge contributors to high emissions and have been closely monitored for nearly 50 years.

Technically the pre-emission battle has been going on since 2007 with 2008 model trucks having to comply with the regulations.

The EPA along with CARB has been victorious in laying new, strict, and ongoing laws for the trucking industry.

With all the sensors the engines have to reduce NOx and cleverly turn it into water and oxygen, it won’t be long before they will bring us down to zero-emission trucks.

Are Pre Emission era Semi Trucks more Reliable?

Typically they are more reliable, however adding on all these sensors can cause issues with the engine and set you back in the thousands.

Veteran truckers are not impressed with trucks fitted with emission technology.

Most of them prefer the older trucks with less to go wrong and more understanding of the mechanics.

I guess it’s a preference but eventually, all truckers are required to comply with the emission regulations.

Do Pre Emission Semi Truck Models have to now Comply with Regulations?

Semi trucks with 2010 engines or newer are fully compliant.

Any model pre-2010 must be fitted with upgrades to reduce exhaust emissions these upgrades must be carried out at certified workshops.

The upgrades are the installment/update of an EGR, DPF, and SCR.

The vehicle must also hold a Certificate of Conformity to demonstrate the engine conforms to the current requirements set by the EPA.

Do Semi Trucks have to Pass Emissions?

A semi truck must comply with the emission regulations and have a yearly inspection of its EGR, DPF and DEF to make sure the engine is performing to the standard set by the EPA and CARB.

Should a vehicle fail this test it will not be allowed on the road until the issue/s are resolved.

The testing also involves a search for particulate matter, black smoke, and soot.

Regular checks of your own can help keep you in business by preventing you from failing the emissions test, do not ignore a sensor they have been put there for your benefit.

Is it Advisable to Buy a Pre Emission Semi Truck?

There are mixed thoughts about this subject with the majority of the current truckers swaying more towards pre emission trucks,

The newbies seem to be the ones heading for newer models mainly through the persuasion of a good salesperson.

The veterans of the trucking world seem to have a phobia of new trucks with all the sensors and advanced technology that could prevent them from doing their jobs, or so they think.

Apart from the cost of a new truck which can be up to $200,000 after interest, the cost of a sensor if it’s not covered by warranty can set you back in the thousands, another reason the veterans try to stay away.

The preference on the pre emission engine is the claim that they were built better and had less to go wrong with them, which is a fair argument however, where do we draw the line?

Should they have not put electric mirrors and windows or air conditioning into the design, in the unlikely event of them going wrong and having more to fix if it did, should they not have added fridges and TVs.

We have to move with the times or die in the past.

We send emails, not a pigeon to deliver a message. We use cars not horsedraw carriages to get from A to B, and we simply flick a switch to illuminate a room, not strike a match.

The truth is technology is making our lives better, although more costly to us the price of a cleaner planet by means of reducing emissions is immeasurable to us and future generations.

In short, the answer is no, not with what the governments have planned for a zero-emission earth.

This may take years to implement however the restriction to emissions will go ahead nonetheless.

Happy Trucking!