Hi All,

So it's about that time for me to get the Axle Differential fluids changed. The dealer off course want's $300+ to do it so I might have it done somewhere else for cheaper. My question is what kind should I use. I want to chane it to fully synthetic and one of the gass stations in my area recomended BG 75-140. I would like to know what you guys are using and which one is the better one. It seems like BG is all over the place lately but I have never used it so I don't know their quality. Is Mobile better then BG? What other kinds are there and what do you guys recomend? My JK is 07 4dr Sahara 4.10 ratio.
Thanks for all the input.
Henri

 

i used Royal Purple full synthetic for both front and rear. This eliminates the need for the additive for the LSD. I think total cost of fluids was a little over $30. Not bad compared to the dealers $300 and it is not hard to change or take long at all.

Took under 1qt for the front D30 axle of 80w-90 oil.

The rear took right at 2qt of 75w-140 oil.

 

I used Mobil 1 75w-90 in the front and 75w-140 in the rear. I picked mobil 1 mainly because thats the synthetic the auto parts store near me stocks.

 

i use mobil 1 synthetic... i however put 75w-90 front and rear...

i did a full service for my 15 thousand miles change... partially b/c mine had a leak from the factory...

drained old stuff...
removed diff cover...
scraped seal...
hosed the insides down with brake cleaner (about one can per diff... looks like new)
resealed with hi temp RTV (redish orange stuff)
reseated and bolt diff cover to abou 25 ft lbs of trq.
refilled with mobil 1 (approx 1 qt front (dana 30) and approx 2 qt rear (dana 44)

all told, i spent about 2 hours (1 hour per diff)... mainly the nasty rtv they used originially took a bit to get cleaned off... brake cleaner helped with that too

edit to add: it can probably be done much faster, but i was extra careful as it was my first time doing this

 

Sorry if this is a stupid question but what is this additive for the LSD? And what's LSD?

 

Not a problem. That's Limited Slip Differential, it takes an addative to allow it to operate properly.

 

x2. I changed mine initially when I swapped out my stock covers for some Solid covers. I used RTV then, but I banged my front differential on a rock awhile back and had to do the front again. That time I used a Lube Locker. I haven't banged it since, so I don't know how good it really does at holding, but it came highly recommended from others.

I used some Castrol semi-synthetic the first time and I used Royal Purple the second time. My choice boiled down to convenience.