I'm concerned about my corolla's front seatbelts on my 91. No matter how hard I try to lock them up I can't. I've tried to lock them under hard braking and yanking on them quickly with no luck. Does this mean I'm going to meet the steering wheel at high speed in an accident? Do they just wear out and don't lock up anymore with the door mounted seatbelts after awhile? The back ones lock up fine. Any advice?