Oh by the way Darren, good looking kids, nice to see you getting them started early liking Mavericks.
Your belts are probably better preserved than mine. Our interiors bake in the sun down here in the tropics. If you do not have window film and keep your windows rolled up, it is not unusual for interiors to hit 140-150F (60-65C).... that would be like everyday, for 4 months out the year. Yours have been kept in the freezer for half of those 34 years.
I replaced my rear seatbelts mainly because of the baby seat. Not that they didn't seem strong, I just couldn't get a tight enough hold on the seat in my opinion. Didn't want it flopping around. At first I wanted to retrofit the "tether and anchor" system for baby seats you find in new cars, but I found a way to make my "new" junkyard seatbelts work great. I just cross them over through the seat and ratchet them down. I snap the right belt to the left buckle, etc. That way four anchor points get to spread the load in the event of an accident, and the seat is very tight. But anyway, when I was looking for rear seatbelts I strolled around the junkyard all day looking for belts that were in the best condition, the right color and a good fit. Lots of newer cars (and a few older ones too) had belts that had clearly seen better days. The mechanism was broken, or the belts were extremely faded (which tells me the threads could be weakened too). The best ones I found by far? '72 LTD. They looked brand new. They're black, even after all these years, Probably because they spend those years retracted) and they're nice and thick, better construction than anything else I found. My boy rarely rides in the Maverick. Mainly just short drives to a local cruise-in. But I feel like he's as safe as can be when he does.
Wow, I had both my kids out in the new mav this weekend. I didn't even think about those possibilities of the belt being bad! Makes me feel like a real dumb---!Well I'm glad this post was here to read, or else who knows when it could have become an issue. Thanks everyone!