I think he might be referring to the crush washers (gasket). I think that's what the service manual calls them.

 

Sorry, I was exhausted last night. I meant the washers, is the same one is used for the Transfer Case that is used for the Differentials?

i decided to use the 75-90 Mobile 1 synthetic fluid as per my research the fluids are similar and in fact I saw two posts on a truck forum where Mobile 1 stopped some noise when someone was using Red Line and another was using some Motul. Plus it is much cheaper. To each their own for brand selection.

 

Couldn't tell you - I'm that guy that reused the O-rings

I used the same Mobil 1 FS LS for three changes now so no worries there. I usually run mine for 30k miles before servicing and the fluid comes out looking great. Odd since the first service was at 40k and the smell was putrid and the fluid was obviously worn.

 

Thank you everyone for the wonderful help so far. One last question, as I hope change out the Front, Rear and Transfer Case fluids out at the end of this week. This will save me a good $220 doing it my self and seems it will take just 1-2 hours.

It does appear my bolts are rusted, at least the rear differential fill plug is when I looked at it today. What is the best way to remove them? Would spraying a good amount of PB Blaster on and around the bolts help to loosen up any rust at all? Then I was thinking to make sure the 10mm hex is fully in there, and will tap it very gently with a mallet or small hammer to loosen up any rust. Then make sure the hex is fully seated before trying to remove the bolts. Would using too much force damage it when removing? I will use a torque wrench when re-installing.

Thanks!

 

Wont hurt to squirt a little blaster on it. Tighten back up just like you would your oil drain plug.

 

I don't see any problem with your plan. I think as long as you are using the correct 10mm hex socket (make sure the fit is tight) and breaker bar you won't have a problem. I used a 3/8 breaker and 10mm hex socket and didn't have to apply much force to break them loose. I suspect that you will have much less trouble with the rear diff even if it looks like there's some rust because you have A LOT more space to work with. If you can find a low profile 10mm hex socket GET IT because there's very little room to work with on the front diff. Be VERY careful on the front when breaking the drain plug free because the oil sensor is RIGHT in the way of your breaker bar and it would be easy to damage the sensor. The only other suggestion I would give is to be cautious when using the torque wrench when reinstalling. It can be easy to overtighten. If it seems like it's pretty snug and the torque wrench hasn't clicked you may want to stop and reevaluate things.

 

Thanks, I plan to buy the 1/2 inch hex socket set from HF for $12 (https://www.harborfreight.com/9-piec...set-67880.html) and use with the following breaker bar: https://www.harborfreight.com/12-in-...bar-60818.html

I am so scared I might mess up the sensor. I guess no way to protect sensor when loosening bolt huh? Anyone have a low profile hex bolt suggestion that helped them or if I am careful should I be ok with the HF set?

 

I just grabbed the short end of the hex style allen wrench with a set of vice grips.

It shouldn't be that tight but a rubber mallet will do the trick in a pinch. A couple light taps will break it loose. Biggest thing you have to ensure is that the hex head is snug and fully seated. Strip them and you're going to have a bad time. Crack both the fill and drain plugs loose before draining.

 

Oh, good idea! Lots of ways to 'skin a cat'. I'm afraid the 1/2 breaker bar and socket is just going to be too big for the small space. Even the smaller breaker bar I used was a tight fit.

 

Absolutely - doesn't matter how you do it, as long as you can do it successfully and save a couple hundred in the end. I believe I tried a breaker bar but didn't have anything that worked in that tight of a spot. The vice grips require a bit of finesse given the angles on the allen wrench style hex heads but I've used it for two service periods without issue.

 

a big +1 on what Waynard said with respect to the front transfer case...watch out for the oil sensor, I broke mine last time I changed the diff fluid exactly how he described, they are so fragile and exposed....luckily they are dirt cheap and usually in stock at local auto parts places...

with respect to tools you won't be able to get that 1/2" breaker bar in the space for the front diff...try to find a low profile 10mm Hex bit, (make sure its for a 3/8" drive, they are easy to find for 1/4" but you will not be able to get enough torque on a 1/4" drive to open it)...I used this set
you will also need a low profile ratchet or breaker bar...I used this one...https://www.harborfreight.com/14-in-...het-67994.html ....I have other low profile breaker bars but couldn't fit any of them with the bit on...

 

Thanks for the solid info! I ended up ordering that Sunex low porfile hex set. Do you think this would work, https://www.harborfreight.com/14-in-...het-67993.html or do you think too short to get proper leverage? Otherwise will get the one you used for double the price.

Thanks!

 

I think that one is too short to really be of benefit in this situation tbh....FYI I think the one I linked to isn't that great either except for the length and I only use it for really tight spots like this... either way they have a $5 off coupon floating around on all Pittsburgh pro ratchets though if you google it

 

I ended up doing this job back in October. It took 3-4 hours, but I took my time. Next time I'm sure I can do it all in 1.5-2 hours if not less. I wanted to contribute something that really helped me:

As everyone stated, loosening the front differential plugs was initially tough as the sensor is right next to the drain plug. However, there is a much easier way to break it loose without even worrying about the fuel sensor. What I ended up doing was using two 3/8 Inch extenders. 1/2" would be too large, so must be 3/8". The extenders I used is something like this, but I did not use this exact kit as I already have several extenders. You have to combine a medium length extender with the shortest extender to get enough clearance to be able to use a ratchet on the other side. If you were to use two medium length together then it would be too long to be able to squeeze in the ratchet. Doing it this way then one most likely won't even need to use a low profile hex bit either. I was able to break the bolt loose in mere seconds. I tried the vice grips earlier and it was just way too hard. Luckily, a neighbor who is a mechanic saw me struggling and suggested the extender idea.

Another tool that really helped was a 3/8" Ratchet from HF but it extends in length by sliding the handle so if you need more leverage you can get it instantly and can shorten it if in a tight spot. I just needed this one "length adjustable" ratchet for the entire job, I can't seem to find it on their website at the moment to link to unfortunately. I hope they still sell it. I ended up returning the breaker bar since I didn't need it.

Also, it was a pain to obtain the proper Matic J fluid for the Transfer Case. Most Nissan dealers no longer sell/stock Matic J fluid. One Nisan dealer claimed they had it, but once I got there and asked for "Matic J" he gave me Matic S saying it replaces/surpasses Matic J. We went back and fourth and I ended up just buying Matic J from the Infiniti dealer next door. It cost much more at Infiniti but luckily I asked politely and they ended up giving me a significant discount, still cheaper then Amazon, who is the only other place I know that sells Matic J other then Infiniti.

Thanks again for the tutorial and everyone else's input. I enjoyed this project overall and the gears/power delivery feels more smooth and the very occasional hard jerks I would get have vanished as proven by going on the 1500 mile road trip right after the job. As everyone else said the rear differential fluid was absolutely dirty and smelly at 52.5k miles. Also bunch of metal shavings were removed. I kept putting the drain plug in and out until there was no more shavings coming out. Finally, wanted to confirm that the gasket is exact same for the Transfer Case and the Front/Rear Differentials. I ended up re-using most as they were in great condition. I only replaced the drain gaskets for each.

Image below of the two extenders I combined:

 

Good advice on the two extensions. I too have an "on-the-fly" adjustable length ratchet from HF. It has been very helpful for many jobs that are tight space, then needing more leverage for the next open bolt and not having to switch tools.
I didn't use Infiniti/Nissan gear oil as many people used Amsoil instead. When i went to buy my Amsoil, I saw these and they worked really well as they were flexible bags and fit into the tight spaces and I only had to use the pump on one differential (dont recall which one).
https://www.amsoil.com/shop/by-produ...BoCWYQQAvD_BwE