I have just been given a couple pair of new Danner boots. Premium leather, GoreTex lined. Every boot I have ever owned, got Mink Oil slathered when new. This is my first pair of GoreTex. Will they respond well to this treatment.
Also The box contained some leather pieces. They seem to be some sort of "Tongue Protector" Should they be installed or just toss them?
I would stay away from mink oil in this case. Mink oil is great for the leather but hell on Goretex. I assume that the Goretex membrane is sandwiched between the outer leather and the boot liner.
If the mink oil (or any animal fat based product) soaks through the leather to the Goretex membrane it will clog the pores of the Goretex rendering it basically useless.
You might try Nikwax Aqueous smooth leather wax which is water based and designed for use with Goretex membraned shoes. The Nikwax does not last as long mink oil but it seems to work with the Goretex.
I have heard from some that the Nikwax makes hiking boots too warm. I use it on my Goretex lined work boots that I only use in Winter and I do not really hike in them so I can't really say for sure.