Originally Posted by Gumball
you can usually tell by the stiching.
if the stiching is soft its leather and if its hard its man made leather.
most touchable parts are real leather. meaning what your body touches.
and the sides are man made.
To be technically correct, this is true. Your "main seating surfaces" are "genuine" leather, whereas the side and back panels are man-made "pleather."
However, it'* also important to note that GM uses what is called "coated" leather. Basically what this means is that a clear varnish-like coating was sprayed onto the leather after the dying process, to prevent staining, and prolong the life of the dye. Since this coating is non-porous, and mostly seals off the leather, no "true leather conditioner" will ever fully soak into the material. Over time, though, this coating does wear away in some spots and should be conditioned better to maintain uniformity with the rest of the seat.
I've found that using some rather un-traditional methods actually are best for GM'* seats (and yes, I know they'll sound unorthodox -- I was a doubter too for a long time until I tried it)
1) Clean the seats with a highly diluted All-Purpose Cleaner (I prefer Meguiar'* EXTRA! or Detailer APC+. Just don't EVER use Simple Green!) and a nail brush to agitate.
2) Coat all seats with Neatsfoot Oil or Baby Oil (Neatsfoot adds a slight waterproofing property) and give it about an hour to soak before buffing off the excess.
3) Re-clean the seats with a pH balanced cleaner like Lexol'* pH cleaner.
4) Condition the seats with your choice of leather conditioner (I use either Lexol or Zaino Z10).
Voila, seats that are as close to new as you are going to get without actually HAVING new seats. Re-do this treatment as needed, but never go more than 6 months without doing SOMETHING to the seats.