Before you spend any more cash on the truck and get in too deep, check the rest of the truck out for anything that may need to be replaced.

It seems odd to me that you had the truck running now the timing chains are bad.

In my opinion you do not have enough information to replace parts yet.

Or you are leaving out much of what the mechanic told you.

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2002 Ford Ranger 2 Dr Standard cab 2.3 5 SPD 7.5 373 gears