As a company that has worked in the automotive undercoating industry for some time, we have had many questions about the quality of factory undercoatings. Is the factory undercoating that comes on your vehicle good enough or should you take further action to better protect your vehicle from corrosion? Since we live in Upstate New York, our answer is always the same; if you want to keep your vehicle for more than five years, you need to take further action to protect it. If you live in an area where there is no snow and no salt being applied to the roads, then your factory undercoating will be just fine.
Every manufacturer is different when it comes to undercoating their vehicles, but in this blog we would like to talk about General Motors trucks and vans 2014 and newer. GM applies a factory undercoating to the frame of these vehicle. This undercoating is a wax-based material that goes on thick but is easily scraped off with your fingernail. From the research we have done, GM dips the whole frame in a vat of hot wax before it is assembled. You can usually see bubbles on the rear edge of the front crossmember, that are actual drips. The frame must be suspended in the air from the front vertically dipped into a vat of wax, then it is pulled out and allowed to drip until its dry. Pretty cool. This is a great way to get 100% coverage in a very short period of time. I have no issue with the process. The issue I have is with the product. Wax based undercoatings can be made with a variety of different fillers. You can add corrosion inhibitors, hardening agents, softening agents, almost anything that you want to get the desired outcome. The wax that GM is using is very soft and peels away from the vehicle after a while. It also breaks down very easily in the right circumstances. If you pour oil and wax into the same cup and mix them together, you will end up with just a thicker oil. Therefore, when your mechanic sprays his penetrating fluid on your GM frame, it will dissolve the undercoating and leave you unprotected in that area. Consequently, if you have your vehicle undercoated at a shop that sprays a oil-based product, it will dissolve your factory undercoating and turn it into a gooey mess. So not only is the oil that they sprayed dripping off your vehicle and leaving you unprotected, but your factory undercoating is dripping off as well exposing bare metal to our harsh environment. Not good.
We had a recent customer come in for Corrosion Protection and they shared this story with us.
They had an oil based undercoating spray applied to their 2016 Chevy Tahoe. They parked it in the cement Driveway because they were told not to park it in the garage when they came out the next morning, there was a outline of wax and oil on the ground in the shape of a frame.
When undercoating these vehicles, you really only have two options. First you can go through the trouble of removing the factory undercoating and power washing with a high temperature pressure washer then apply an undercoating of your choosing. The second option is to spray a wax-based undercoating over everything. Wax based undercoating will adhere very well to the existing wax as well as any other non-coated metal under the truck. Most wax based undercoating are more durable and have better corrosion fighting properties than the factory GM one. GM doesn’t care if their undercoating lasts forever because they want you to buy another truck as soon the warranty runs out. Their undercoating is made to get you through their warranty period and not much further. The only other option is a rubberized undercoating that hardens. I don’t even like talking about these because they are a thing of the past and do more harm than good by trapping moisture and accelerating rust. I’m not sure it would stick to the wax coating anyway.
If you want to keep your vehicle for more than five years, get it protected. If you own one of these GM trucks, be very careful what you choose to spray underneath. We recommend Waxoyl’s two step process. They have one product for cavities and another for the undercarriage. This is a very durable wax with corrosion inhibitors that stop rust. Keep your underside clean and fight rust!
