Front & Real Differential Fluids

[nfpgasmask]

So, I wanted to start a thread for info on our differentials and what kinds of fluid to put in. I know we need some LSD in the rear, but I have no idea what to buy or how much.

I also would like to get a good step-by-step from someone who has done their diffs so I can do mine. I did a search and couldn't really find a solid thread about this.

Ldub, I nominate you to write this up for us!

Bart

[ZEUS]

I'm running Royal Purple in there too - check the manual for rec. weights and amounts.

[nfpgasmask]

I'm running Royal Purple in there too - check the manual for rec. weights and amounts.

Yeah, I printed the whole thing out last month, I might as well use it, eh? So RP diff fluid in the front and rear, and what about your LSD fluid? What did you put in? Are they easy to drain and fill? Do you need to pump it in or syphon it in like the tranny?

Bart

[ZEUS]

Everybody keeps forgetting I have an open rear diff - no LSD. But to my understanding, Royal Purple has qualities in it comparable to an LSD additive already. Check it out. The front is easy to drain and fill - the rear I think is easy to drain but a little more challenging to fill. The front is just a bolt that is removed - it is the bolt at the very bottom of the 3rd member. It acts as a bolt and a plug. Once fliud stops coming out, put the bolt back in and fill er up until fluid starts coming out of the fill hole then plug it again. I think we had to pump fluid into the rear diff but it has been over a year and a half ago, so I forget.

[nfpgasmask]

Everybody keeps forgetting I have an open rear diff - no LSD. But to my understanding, Royal Purple has qualities in it comparable to an LSD additive already. Check it out. The front is easy to drain and fill - the rear I think is easy to drain but a little more challenging to fill. The front is just a bolt that is removed - it is the bolt at the very bottom of the 3rd member. It acts as a bolt and a plug. Once fliud stops coming out, put the bolt back in and fill er up until fluid starts coming out of the fill hole then plug it again. I think we had to pump fluid into the rear diff but it has been over a year and a half ago, so I forget.

So there is a drain and fill plug, just like everywhere else. I bet the syphon method will work good.

Hopefully some others will chime in with what fluids they are running in their diffs. Thanks, Justin.

Bart

[JHarris1385]

I forgot the brand but I used syn with lsd in the back. Better to be over than under on your lsd. I forget the amounts and numbers but I swear I have a thread on this somewhere. MAKE SURE to be on a level ground. I did not have to use any funnels or syphons at all. I just cut the tip of the bottle to an angle.

[Joe Isuzu]

I did it recently, I'm probably the only person that didn't go synthetic but I read the bottle and made certain it had all the necessary acronyms other threads said we needed
also, doing this was FAR easier than the tranny job, nothing to remove other than the drain and refill bolts, probably the hardest thing was to find the drain tube for the front axle
and the bottles have nice little tips on them, it wasn't as easy as simply squeezing in the fluid, but it was very easy to squeeze the fluid into a plastic tube and put the tube in the fill hole
going by memory, it should be like 2 hours tops for both, the more times you do it, the quicker it will be

[kodiak]

I did it recently, I'm probably the only person that didn't go synthetic but I read the bottle and made certain it had all the necessary acronyms other threads said we needed
also, doing this was FAR easier than the tranny job, nothing to remove other than the drain and refill bolts, probably the hardest thing was to find the drain tube for the front axle
and the bottles have nice little tips on them, it wasn't as easy as simply squeezing in the fluid, but it was very easy to squeeze the fluid into a plastic tube and put the tube in the fill hole
going by memory, it should be like 2 hours tops for both, the more times you do it, the quicker it will be

Thanks for the info, It sound like a painless process and besides I like working on my baby.

[Triathlete]

I am running Mobil1 and I added a bottle of LSD additive. It won't hurt to put it in, it can hurt if neded and not used and there seemed to be differing opinions on weather or not it was needed with synthetics. It is cheap insurance...somewhere around $5 for a bottle/tube (whatever it came in).
It is a fairly easy job (probably a 2 out of 10). I found my drain hole on the front to be clogged. Also found that a cheap fluid pump helps to make it easier but is not needed. Good luck!

[nfpgasmask]

I am running Mobil1 and I added a bottle of LSD additive. It won't hurt to put it in, it can hurt if neded and not used and there seemed to be differing opinions on weather or not it was needed with synthetics. It is cheap insurance...somewhere around $5 for a bottle/tube (whatever it came in).
It is a fairly easy job (probably a 2 out of 10). I found my drain hole on the front to be clogged. Also found that a cheap fluid pump helps to make it easier but is not needed. Good luck!

Billy, so Mobile-1 makes a synth for the diffs. I might as well use that since I am already Mobile-1 everywhere else. Thanks.

Bart

[Ldub]

Go for a 5-10 mile drive before you drain, to get as much gunk in suspension as possible...also drains better when warmed up.

As mentioned earlier, the lowest bolt that fastens the front third member is used as the drain...bring a coat hanger under there with you, it'll most likely be clogged.

Look at which side the rear drain hole is on & jack up the other side of the axle a few inches, if you want to drain out the most old stuff possible.

Most gear lubes come in a bottle with a longer tip, so you can squeez them into the fill hole, even though it's on a verticle plane.

[circmand]

I have never done it to my knowledge and am at 50000.
I think they need to add an icon of someone scratching their *** to cover my postings

[tomdietrying]

I asked that question a few years ago. Here's what Tone wrote to me:

Quantities have been posted many times before and are also listing in your owners manual - please try the search function.

Approx amounts are as follows:
Tranny flush - at least 10 qts Dexron III
Tranny filter or drain - 4 qts Dexron III
TOD/Transfer - 2qts Dexron III
Front diff - 1.5qts
Rear diff - 2qts
75/140 in both is fine in Texas unless we have a cold winter

Can't change any fluids too often - see manual for time/mileage periods

@ 30K you also should be having your wheel bearings repacked....

Hope this helps.

Peace.
Tom
012009

[nfpgasmask]

Thanks Tom. Much appreciated. I'll be doing this soon with the Reno boys, hopefully.

Bart

[MSHardeman]

Bart,

I just found shop with a couple of good guys, and they are pushing the "green" thing. They use Amsoil exclusively and I recently had them replace my front and rear diff. fluid, transmission fluid, and transfer case fluid with the stuff. Apparently Amsoil has been "synthetic" since like 1920 (it's a corn based lubricant) and it's supposed to last forever. Well, not really, but Amsoil states that the transmission fluid is good for 500,000 miles. They also state that their oil is good for 25,000 miles between changes. There are some additives that you have to pour in every now and then, but that's about it. I didn't do the oil because I just don't trust a 25,000 mile oil yet.

Anyway, all of that is to say that when they where changing the fluids out they said that the old stuff was in fantastic shape and could have gone another 70,000 miles (the VX just turned 70k after Moab). To my knowledge those fluids where never changed by the previous owner so it seems like Isuzu put some good stuff in there to begin with.