They are made of steel.
I've seen some get slack in them after like 100,000 miles but I've never heard of any breaking. Those double chains are strong as hell. It would be a good idea to replace them if you have more than 10,000 miles on them and the timing chain cover is off.
I've seen some get slack in them after like 100,000 miles but I've never heard of any breaking. Those double chains are strong as hell. It would be a good idea to replace them if you have more than 10,000 miles on them and the timing chain cover is off.
