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Lowboy Motorsports Under-Bed Ingenuity Shipped to your Door Photo Gallery
As Simple as A, B, C-Notch
Bryan Fross –
Jan 22, 2019
Photo 1/26 | Lowboy Motorsports C Notch 01
Photo 2/26 | Lowboy Motorsports C Notch 01 | Before: Here's our ’18 Chevrolet Silverado with a 4-inch lowering kit. At this height, the rear of the truck is still higher than the front. The Lowboy Motorsports C-notch is needed to allow axle travel after the other changes to the rear suspension to make it a 6-inch rear drop.
Photo 3/26 | Lowboy Motorsports C Notch 02 | The truck was pulled up to the lift at Lowboy Motorsports, where the crew began removing the rear wheels, tailgate, bed bolts, and bed, making sure to unplug all electrical harnesses and the fuel filler neck. The gas tank was also removed prior to any work beginning.
Photo 4/26 | Lowboy Motorsports C Notch 03 | The pieces to the Lowboy notch kit vary by application, but this is the initial kit for the ’18 Chevy.
Photo 5/26 | Lowboy Motorsports C Notch 04 | Using a bend line that has already been pre-cut into the parts, the notch is shaped for each application before it is installed or shipped to the customer.
Photo 6/26 | Lowboy Motorsports C Notch 05 | Here is the kit after the top and bottom bends have been completed.
Photo 7/26 | Lowboy Motorsports C Notch 06 | The truck frame was then prepared for welding. This is a tedious process, as the factory coating and grime buildup can be hard to remove even with a sanding disc. Acetone was used to help scrub off the coating down to bare metal. The center line where the axle lines up was measured and drawn onto the frame for easy reference.
Photo 8/26 | Lowboy Motorsports C Notch 07 | The center line was then marked on the notch side piece, and the bend lines were drawn for each side. Here's where the Lowboy Motorsports notch differs from others on the market. The side piece is marked so that it can be bent to fit flush with the factory frame curve. Otherwise, there would be a large gap if a standard flat piece was used.
Photo 9/26 | Lowboy Motorsports C Notch 08 | The slight bends are made at the markings to make sure the product matches the factory frame angles.
Photo 10/26 | Lowboy Motorsports C Notch 09 | You can see the slight difference from this angle when they are laid on a flat surface.
Photo 11/26 | Lowboy Motorsports C Notch 10 | When clamped in place onto the frame, the piece now follows the factory frame angle change.
Photo 12/26 | Lowboy Motorsports C Notch 12 | The other side was matched up with its counterpart after being bent to fit in the same way as before. Other truck makes and models have minor differences in the preparation of the underbed notch, which is why templates are kept on hand so the product can be bent or cut to fit right on your truck.
Photo 13/26 | Lowboy Motorsports C Notch 13 | The sides were lined up, measured, clamped, and fully welded into place.
Photo 14/26 | Lowboy Motorsports C Notch 14 | On the ’18 Chevy, the center bed brace can be cut out to get the maximum possible space without cutting any of the bed floor out. Then the remaining edges were sanded down to remove any burrs or rough spots.
Photo 15/26 | Lowboy Motorsports C Notch 15 | Then the bed could then be painted or coated to cover the exposed bare metal.
Photo 16/26 | Lowboy Motorsports C Notch 16 | The top was test-fitted after a slight bend to line up with the side bends. You can see that the top and sides match up perfectly to allow maximum welding surface area between the separate pieces.
Photo 17/26 | Lowboy Motorsports C Notch 17 | With the top sides welded in, you can see here that the axle will have much more room to travel without contacting the frame.
Photo 18/26 | Lowboy Motorsports C Notch 18 | The rest of the top is welded together, filling each gap equally and consistently.
Photo 19/26 | Lowboy Motorsports C Notch 19 | Here is the finished top piece, which was examined carefully before the next step. Any issues could lead to stress cracking sometime in the future if the welding isn't complete.
Photo 20/26 | Lowboy Motorsports C Notch 20 | The factory frame section under the notch could now be cut out. Once removed, the surface area for the last notch section was visible all the way through.
Photo 21/26 | Lowboy Motorsports C Notch 21 | The bottom piece was lined up flush with the bottom of the side sections and welded into position.
Photo 22/26 | Lowboy Motorsports C Notch 22 | The undersides of the side pieces were also welded for full strength of the new section.
Photo 23/26 | Lowboy Motorsports C Notch 23 | The minor overhang of the notch sides could then be cut off. This extra section was left on the sides to allow for some adjustment and repositioning before any welding was started.
Photo 24/26 | Lowboy Motorsports C Notch 24 | Using a sanding flap disc, the notch is cleaned up and readied for paint, powdercoat, rubberized undercoating, or whatever you choose.
Photo 25/26 | Lowboy Motorsports C Notch 25 | Here's our finished Lowboy Motorsports underbed C-notch. When the coating is dry, the disassembly process is reversed to reinstall the gas tank, bed, and tailgate.
Photo 26/26 | Lowboy Motorsports C Notch 26 | After: With a few changes to the aftermarket drop kit on the truck and new shorter shocks, the rear sits 2 inches lower and the axle will no longer hit the frame with every bump in the road thanks to the underbed notch. Get in touch with Lowboy Motorsports to see what options are available for your truck.