best gear lube for rear diff

I have an 01 with a 2.7, It has just over 100k, I drive about 60 miles a day, just wondering what you all prefer to run! Thanks.

Nac

 

I have never changed mine, but Lucas Oil is probably good stuff.

 

x2, i just did mine with M1

$30 75w-90 Synthetic Gear Lube - 1 Quart (Pack of 2)

75w-90. I wanted to use 75w-140, but didnt want to spend 20 bucks a quart.

 

I think lucas is some of the best. i just used conventional not synthetic. not something your really going to tell a diffrence with. Especially since your supposed to change out every 30k miles. Not really worth the extra money for synthetic imo

 

30k is a lot of miles, and a long ass time for some people. For me, it's about a year. I trust that synthetic will not break down like conventional will over that amount of time and miles.

 

synthetic you don't even get your diff hot enough to ulitilze the oil. Seems like a waste of money. I just used dino oil for my arb's.

 

synthetic vavoline is what im runnin

 

I'm wondering though...I notice my roll distance and speed are affected on the cold morning start ups. With synthetics, resistance might be less on cold mornings. Just thinking out loud...

 

I am going to go ahead and guess that, that is because the grease in your wheel bearings is cold. It is actually a combination of all lubricants being cold and more viscous than at operating temps.

Full synthetic will more than likely not make a noticeable difference at all.

 

http://www.lubegard.com/~/C-197/LUBEGARD+Gear+Fluid+Supplement

 

For the first five miles the difference is huge when its below freezing. Dino oil is like tar at 10 degrees; synthetic will at least flow somewhat. If you want to see for yourself, try running dino lube through a hand pump when it's that cold. Darn near impossible. The synthetic will give you cramps but at least it will go through the hose.

In the summertime it won't be a big deal of difference but with it I still saw a small improvement in the overall mileage trend.

Personally I use Redline GL5, mostly because I'm already buying a bunch of MT-90 for the tranny and transfer case and I like to do them all at the same time.

 

Some trucks go their lifetime without getting their diff fluids changed, I wouldn't personally do it to a $30k truck..

 

Mines been about 100k since I've changed it. A lot also depends on if you drive through water, mud, or sand.

 

Oh and you don't do any of that do you?

 

as an amsoil dealer i reccomend lucas i think 90-140 was the weight,


then again if you wanna spend some money you can always buy amsoil

 

I use

$24 Red Line 57904 (75W90) Synthetic Gear Oil - 1 Quart

Red Line 57904 (75W90) Synthetic Gear Oil, since it has the best temperature rating. Up and down some steep hills with a half ton of mulch or stone and that diff gets H-O-T!

 

Try not to.

 

MIgander, TT,

Thanks for the responses. I suspect that moving to full synthetics (grease and oil) would help improve the cold morning starts and improve vehicle performance (MPGs). I'm at the point that I will need to do the lubing - already squeezed in synthetics into the Universals and driveshaft. Getting warmer now, so the real difference wont be known until next fall/winter...which is fine by me.

 

At 30K, I went full syn. with all my oils. Rear diff was filled with Amsoil 75-90 Severe Gear Oil. Factory oil still looked great, like new. Manual tranny oil showed more wear in the color, but was only a medium tan and still good. Just as an FYI...

 

I used Nissan's

$30 75W-90 Synthetic Gear Lube - 1 Quart (Pack of 2)

75W-90 gear oil as it was free since I worked at a Nissan shop. Haven't Had any trouble.