I studded my track three seasons ago and I installed tunnel protectors that my friend told me were the right size. Well, I don't think they were beacasue after about 5 minutes of running the sled in the garage, the protectors cut right through my lugs. Were they supposed to do that? I thought the lugs were supposed to hit the protectors and not get any closer to the heat exchanger. I have not had any damage to the heat exchanger, so I am assuming all is well, but I want to know if that was normal?