Gear Oil - 75/90 vs. 75/140
Need some advice, on an original geared 178k mile '94 LC, any opinions on running Mobil 1 Syntehtic 75/140 to quiet the pinions down a bit? I have read on re-geared (bigger gears) trucks, it is sometimes works to use 75/140 to quiet them down a bit but, wasn't sure on stocking gearing with the mileage my truck has on it. The LC currently has 75/90 non synthetic in it. Thanks in advance!