Diesel Oxidation Catalysts (DOC) are catalytic converters designed specifically for diesel engines and equipment to reduce emissions of carbon monoxide (CO), hydrocarbons (HC), and particulate matter (PM). DOC’s are simple and suitable for all types and applications of diesel engines and play a key role during the ‘regen’ process.

Often, changing the DOC is overlooked, as many techs focus their attention on the DPF.  However, leaky oil from the turbo or leaking coolant from the EGR can adversely affect the performance of the DOC and its ability to perform the catalyst reaction with the emission gases. Age and excessive idling also contribute to the wear and tear of the DOC. Normally under optimum conditions, the DOC should outlast the DPF and be ok if the conditions upstream from it and within the DPF show no adverse signs or conditions. Although, that is the best-case scenario. Often, the DOC gets ‘pionesed’ from upstream engine issues, which weakens its performance and further compromises the DPF.

If only changing the DPF, a good practice is to do a temperature rise test by way of a forced regen to ensure the after-treatment system can complete the regen cycle and monitor if proper temperatures were reached during the forced or manual regen. If not, it could be time to change your DOC.

At DPF Canada, you can source lower-cost aftermarket DOC filters, which are always brand new manufactured units. Most include the clamps and gaskets, and we never have any core charges or core returns to hassle you with. We have great availability from multiple brands having warranty options for you to choose from.

However, no matter where you get your parts, it's important to ensure they are high-quality and compatible with your truck.

That's where DPF Canada comes in. We provide free shipping on high-quality diesel truck DPF & DOC’s replacement parts in Canada and the US.

When shopping for aftermarket DOC filter replacement parts, there are a few factors to consider. You must first know the correct part number to effectively assess the precise components required. There is no point in getting pieces you will never use. Second, ensure the components you purchase are suitable for your vehicle. All trucks are built to specific standards, and aftermarket parts may not meet those standards unless examined by an aftermarket supplier to ensure a proper cross to your OE part number. At DPF Canada, we research to ensure aftermarket compatibility with the parts you're looking for.

Finally, you must ensure that the parts you buy are high quality. There is no point in spending money on parts that will break or wear out quickly.

Once again, at DPF Canada, we only source high-quality aftermarket parts that have stood the test.  Since our founding in 1998, we expanded into DPF cleaning and aftermarket sales in 2007, and after that, thus we know the DPF & DOC supply market well.

You've come to the right place if you're looking for an aftermarket DOC diesel filter for your truck. We can help you locate the parts you need, whether it's an aftermarket filter we list online or a model you don't currently see on our website. If we don't have what you want, please contact us, and we will do our best to help.