Wire Splicing: Solder Sleeve vs Butt Connector

I am fixing some motor sensor wires and need to splice and seal the wires. There are two interesting options, solder sleeves and butt connectors. Both options heat shrink to be waterproof. The difference is that butt connectors are crimped whereas solder sleeves are actually soldered. Are either of these options much better for this application? SX679 HTB1vf7QHpXXXXXZaXXXq6xXFXXXL_39c2628e-86b4-4782-aafb-78bd2ff47b03_1024x1024%402x

If you properly crimp the butt connector, it’s technically better. A cold weld. Soldered connections mid-wire are more prone to breakage via vibration, especially if it doesn’t get flowed correctly, or is heated for too long and wicks far up the wire where it shouldn’t.

Personally, I would solder it with a good iron or a torch with actual solder - not a sleeve, aside from that, crimp it with a real pair of hydraulic crimpers.

Just as a second option, @Andy87 is making longer sensor extension adapters for dirt cheap.

Probably cheaper than you’d get a set of solder connectors