I've been reading about the need to add some sort of sealant along with regular antifreeze when flushing the system . What is it and how much do I need to add ?

I've been reading about the need to add some sort of sealant along with regular antifreeze when flushing the system . What is it and how much do I need to add ?

Use the "search" feature at top of this page and type in coolant tabs,tons of info.

walmart has it radator sealant its powder fourm and the color is gold use i think 2 wont hurt. our go to your cadi dealer and get the tablets.put in bottom hose.

Do I really need to pop a hose off - or can I remove the cap and insert them there ??

RTFM. There should also be a sticker on or near the radiator support (possibly with with the emissions, belt or vacuum information) that specifies whether to use the tabs. Barr's Stop Leak are the same thing. That said, I don't recall if they are required on 4.9L engines. I thought that was a N* "feature." On my 99 there is a lable on the radiator cowl that specifies putting the tabs in the lower rad hose - I'm assuming there's a reason for that. I put them in a plastic bag and hit them with a hammer first and just pour the dust in.

Before you go dumping Bar's tablets or 12 powder into a cooling system, it would be a good idea to research which engine you have and search threads with that in mind. What's recommended for different generation N*'s is usually not recommended for non-N* engines.

Best to find out before you start draining, flushing, and removing hoses.

Per our old Guru, the sealant tabs are "Required" in the 4.x engines (4.1, 4.5 & 4.9) and "Recommended" in the Northstar. That said, up until '01 or '02 there where stickers and notes in the FSM "requiring" their use. Mine does not have them. I even quit using them on my wifes 3800.

The Guru's explanation was that the 4.x engines could get coolant in the oil if an intake manifold gasket leaked. Not so with the Northstar. Head gaskets are irrelevant as they cannot be sealed by any sealer.

Bottom line is that the 4.x's seem to be required and the Northtars seem to be precautionary.