Short test with conventional gear lube and Valvoline Synthetic
I had some work done on my rear lockers, so after they were finished the dealership filled the axle with the stock Chrysler dino oil. I ran it for a week and measured the temperature. It was 145ºF when I got to work (back roads, slightly down hill), and 162ºF when I returned home (same roads, slightly up hill, and higher ambient temp). For 5 days the temps were within 1 degree. I changed out the lube with Valvoline Synthetic 75w90 and with my drive to work it was now 137ºF and my return home it was 148ºF.
I figured the synthetic was better (it’s higher than GL-5 because it’s also MT-1 and SAE J2360), but it was nice to see that it does keep the axle components cooler.
2008 Rubicon - 2 Door - Flame Red - Automatic - MyGIG - Power Group - Deep Tint.
AEV Pintlers, BFG KM2s 35x12.50x17, Bulldog Fab Stubby Bump, Currie F/R Adj Trac Bars, Daystar Upper Dash, FireStik FireFly antenna, Kilby Rear Shock Skids, LoD Sig Stubby Bump, Midland 75-822 CB, Mopar Filler Door & Locking Gas Cap, Rancho LCA Skids, Rancho Oil Pan Armor, Riddler Diff Covers, custom Rubi Sliders, Sylvania X-treme Headlights, TeraFlex 2.5" Spring Lift, Warn PowerPlant HD, Woods Evap Can Relo, Woods SS Relo, Yukon 5.38s