Do I need new coolant hoses to install this?

Hose connections are OEM-spec, so your existing hoses should reuse the same ports. Inspect rubber for cracks or degradation before reinstalling — if they're original to the car, replacing them at the same time is smart preventative maintenance.

What coolant should I use?

Use VW's G13 or G12 spec coolant — your owner's manual confirms which generation your Jetta requires. Mixing coolant types or using generic fluid can reduce heat transfer efficiency and void warranty.

Do I need to bleed air from the cooling system after installation?

Yes. Air pockets reduce cooling performance and can cause overheating. Refer to your service manual for the correct bleed procedure — some Jettas have a dedicated bleeder valve on the radiator neck or thermostat housing.