I have two Red Max 2500 trimmers. One is 4 yrs. old the other is 5 yrs. old. I alternate using them . Last year the oldest one needed a new coil. This year the newer one needs a coil and it is back ordered. Anybody else have this problem? Otherwise they have been trouble free. And my dealer says they are out of warranty. I thought i read somewhere that Red Max had a lifetime warranty on there coils. Anybody know anything about this. The manual does not say this part is warranted for life.