That also depends on the person making the shaft, i can set up a seamed tube to not need weight when building it.
Sometimes if they don't keep the run out low and just slap it together to specs they'll need more weight also.
Dom doesn't mean it balances better, the weld yokes and slips are still part of the shaft and also play a role
Losing the 2pc will get you better acceleration and better mileage, simply from losing all that driveline weight, you'll also lose any hanger bearing issues.
I never record lengths everything can be different, i always have everyone measure as needed, and that is the best way, seen to many variations from car to car and truck to truck
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