So i did a mondo suspension overhaul last weekend. Did the following
H&R springs
Boge TurboGas
Strut mounts all around
New strut boots all around
Tie Rod ends (front)
Ball joints (front)
Brake lines all around
8 hours labor. 1 cup coffee, 2 mountain dews

Saturday
Pull fronts, find mismatched struts. One is a Cofap i think. Other is a Koni adjustable that was blown (bunch of oil in the housing) Threw them away. Good riddens.

Sunday
Before I started, I thought, hmmm. What kind of struts are in the back. They didn't seem that bad before. Finally get them out and low and behold, Yellow Koni sport adjustables. Hot DAMN.
Cleaned them up, pushed the rod down, adjusted them to half stiff and re installed.

After getting it all back together, I can tell you that there is a VERY big difference between Boge and Koni. Now the only thing I need is a set of adjustables up front. I somehow need to sneak that in without the wife knowing ;)

It's ATF, it's there to transfer heat and help cool the strut!!!

I don't think warranty is possible. If you aren't the original owner, I don't think they do much. Might be worth a try though.

There was a LOT of oil. and the strut moved in an out like an accordion. The previous owners bottomed it out or something, because the bumper was split in half.