Thor Audi A4 Skid Plate Installation Instructions

Now that you have familiarized yourself with the parts of the skid plate and prepared the tools you will need to do the job, you’re ready to get started.
Step #1: Drive your car onto a set of car ramps or jack the car up and place jack stands under the vehicle for safety. Also make sure to apply your emergency brake, (we recommend using both the ramps and the jack stands). Start by removing all of the plastic skid plates using your flat head screw driver. Also you will want to remove the metal bracket that is located just behind your lower sub frame. It is the black metal bracket that attaches to the frame with two 10mm head bolts. The following picture shows this bracket.
Some of the newer A4’s will have an extra plastic piece under your front fender liner that needs to be removed. It is held on with one Torx screw that is located directly in front of the tire in the fender well.
Once everything has been removed you will have access to the whole underside of your vulnerable engine compartment. Depending on the engine and transmission type, it should look similar to the following picture.
Step #2: Next you will be installing the two Rivet-nuts into the two existing Hexagon shaped holes on the rear sub frame located right behind your oil pan. There are only two holes there that are shaped this way so they won't be hard to locate.
Step #3: To install the Hexagon Rivet Nuts you will want to take one of the 10x40mm bolts in your kit and slide the gold colored washer onto it. Then insert the bolt into the hole on the flat aluminum install tool and then slide the star washer onto the bolt as well. Next you will want to grease the threads on the 10x40mm bolt just like in the picture below. Now simply thread one of the Hexagon rivet-nuts onto the bolt until it is tight against the star washer.
Now simply insert the Rivet Nut that's on the install tool into either hole and tighten to 35 foot pounds torque. While tightening the bolt, make sure the head of the Rivet Nut stays flat against the frame by holding upward pressure on the driver while tightening the bolt. Also the flat aluminum install tool acts as a wrench and will need to be held in place so there is no spinning of the rivet nut. Once tight, remove the bolt and repeat the same procedure for the other Rivet Nut. Don't forget to add more grease to the threads of the bolt.
*Note: What is happening when you’re tightening the bolt is the piece of the rivet-nut inside the hole is basically mushrooming down and pinching the metal causing it to stay very tight. Tight enough to the point where it won’t spin when you are finished. Be careful not to strip the threads on the rivet-nut, it takes a lot of strength to do it, but it is possible. Here is an uninstalled (Left) and an installed (Right) picture of a rivet-nut.

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