Photos are from my 2004 Escalade ESV, but it's 98% Suburban/Tahoe so getting opinions on multiple sites. I've been smelling a fluid that smells like hydraulic fluid (just took a whiff of brake and power steering fluid, and those smell nothing like this), and wasn't sure the exact source. Decided to look under the Escalade today, and took these photos; Looking up from the front axle by the brake line and frame; Similar thing is happening on the other side at the same spot. I know the seals (I think pinion?) can be replaced, but I think the procedure is pretty involved, and the case needs to come off, if memory serves. I haven't checked the fluid level, because when I took these pictures yesterday, I just arrived home, and wasn't about to burn my hands on hot engine parts. Shadetree mechanic buddy says all of these IFS trucks leak, and mine isn't that bad. I should just quit whining and top off with fluid. But burnt diff fluid isn't the most pleasing aroma.