LightningSVT-
That's a good question about cleaning leather. I assume by your user name that this dog slobber is on the leather seats of your Lightning SVT.
I've tried using Woolite (yes, the laundry soap for washing wool in) per resident-Autopian Scottwax's suggestion. It works OK.
For real deep cleaning though, I've used Optimum's PowerClean (OPC) on coated leather only. Most "pedestrian" vehicles have coated leather, including your Lightning.
I REALLY dislike the smell/ fragrance that OPC leaves behind, though. I did my car's carpets with it; never again. (Personal preference)
I've also used Meg's Detailing Line D101 All-Purpose Cleaner(Meg's APC) works great (though not as well as OPC!), but the smell/fragrance is MUCH more agreeable.
It's probably time for me to set up to the plate and buy and use a true leather-dedicated cleaner, like Leather Masters or Leather doctor. I know some like Leatherique, but it requires some time and heat to use the Rejuvenator first and then the Cleaner. I hate to admit I use Lexol for my "protectant". The soap/cleaner is kind of weak and not worth the effort. After reading about it within this forum, I can see why some Autopian pundants say use the cleaner/soap and the protectant on horse saddles, belts, and shoes only.