While driving, the truck began to violently shake when downshifting. As I was exiting the highway and braking, the shaking intensified, and the truck stalled while I was traveling around 30 MPH, causing a complete power loss. To avoid a collision, I veered off the ramp and ended up scraping a road sign, which caused damage to the bed above the right fender, the road sign was intact and there was no damage to the sign. When I attempted to restart the truck and placed it in drive, it accelerated on its own. Applying the brakes only made it accelerate further, causing the truck to lunge forward uncontrollably. I managed to slow it down by putting it in neutral, regaining full brake control. I was able to get the truck to my driveway, but as soon as I turned into the driveway, it stalled again. I had to repeat this process to make it home as I didn’t have cell service and was unable to call for a tow. This issue is extremely concerning, a complete power loss while driving, especially one that forces you off the road to avoid an accident, poses a grave safety hazard. My life and safety were jeopardized due to this malfunction.