Last month with the help of Muscle Car Restorations, we showed you how to replace the rear framerails on a B-Body. The outline we gave is basically applicable to all Mopar body styles, and we hoped it would give our more experienced, hands-on guys a guide so they can save their Mopars, if the need is there. Now we also realize that many of our readers may not be able to tackle such an in-depth and seemingly complicated job at home, but what's a guy to do? What if you really want to drive your Mopar, but you have found a rusty framerail or rails that just make it unsafe to drive the car. Whatever you do, DO NOT simply get rid of the car because you don't think it's fixable without major surgery. It is fixable, and we're here to show you how.
Short of doing a complete frame replacement, how is a guy to fix such a dilemma? Enter Safe-T-Cap-a specialized manufacturing division of Auto Rust Technicians that is dedicated to the rust repair needs of the Mopar crowd. Safe-T-Cap repair kits are made to work with the remaining solid metal in the frame to give the car a new lease on life. Some of the kits slip over the existing frame, and some are replacement sections that can be welded in place. All repairs, when properly installed, make the car as strong as, or stronger, than new. All kits come with complete instructions and are intended to be used by people with average auto-body welding skills. If you are not a welder, you may find that your local body shop will be able to install the kit for you. Or, if you are so inclined, you can travel to Rhode Island and Auto Rust Technicians can install them for you.
The first thing we needed to do was get the car up on jackstands and remove the fuel and brake lines, the gas tank, and rear suspension.
When we realized the rear framerails of a buddy's Challenger was in dire need of repair, we decided to see just how easy a repair with a Safe-T-Cap would be. So we ordered right and left rear framerail repair pieces and got to work. As we dug a little deeper, we found that the rear shock crossmember was held in place by two bolts going into the trunk floor-we definitely needed to replace the crossmember as well.
All in all, the repair of the entire rear frame section was really simple, and we did it with one weekend's time, basic hand tools, and a MIG welder. It really was like the guys at Auto Rust told us: "If you have general bodywork skills, you can do it." They weren't kidding; it really is something that can be done at home.
Not only does Safe-T-Cap sell the rear repair kits, but you can contact them for just about any portion of a frame repair that your A-, B-, or E-Body needs.
Once we realized the rear shock crossmember was held in place by bolts through the trunk floor, the extent of the rust was evident. This was definitely not the right way to fix a rusty crossmember and framerail. In hindsight, if the air shocks were pumped up, they would hold the crossmember up against the floor. Look, a good use for air shocks! | 
Here you can see the actual area where the rust has completely destroyed the framerail. The piece missing was stuck to the crossmember when it fell out. | 
This is another way NOT to repair rust. This quarter-inch plate of steel did nothing except cover it up. |
Before any repairs can be made, the area needing the repair and the surrounding area must be clean. In our case, we cleaned both entire framerails with a scraper, wire wheel, and lacquer thinner to remove the undercoating. This will take a lot of elbow grease if your car is undercoated. In our case, the car had factory undercoating, a layer of rust, and some heavily applied aftermarket undercoating apparently to try and help hold the frame together. | 
Before you do any cutting of the Safe-T-Cap, make sure it fits! Remember, these caps will need to have certain areas trimmed due to different tolerances of the car's original frame. | 
Before we put the cap in place, we made sure to treat the original framerails with a rust neutralizer. |