If I understand correctly, you're asking about the transmission fluid in a Suzuki - a Vitara?
If it has a manual transmission, it would be 75W90 (well, you can use a few other weights, but that's what I use). If it's an automatic transmission, I have no idea. Who here has an auto? (Eric?)
Or, are you talking about the transfer case (2 Wheel Drive/4 Wheel Drive selector) - That uses 75W90 also.