I use the 75/140 severe gear

 

i use LE 1605

 

Depends on whose recommendations you're reading and your driving. I'm currently changing mine every 15K based on xviper/repiv's recommendation.

 

I use Mobile 1 75w-90 for diff and I change it and my tranny every other oild change to be safe not sorry FTW

 

I also use Mobil 1 75w90

 

LE1605 is highly recommended. read the oil journals/FAQs near the top of the forum.

 

Changed my differential fluid for the first time yesterday with Mobile 1 75W90 (just over 15,000 miles). The new bottle had LS on it, not on an earlier bottle? With pump dip tube not going all the way to the bottom and car not quite level (slight nose down), wasn't sure that it was filled to the bottom of fill hole. Didn't take much of the new bottle to fill it up with car more level. (Rears on ramps, front tires slightly uphill).

 

hell yes! This stuff is awesome.

 

Mobil 75w90 and suprisingly didnt need to jack the car up or put it on ramps to get fluid change done. How can you tell whether one gear oil is better then another?

 

Aside from getting the oil analyzed before and comparing it to other, its alot of opinion based on experience. I would say that any new oil is going to feel amazing compared to the old stuff that has been drained.