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Rear diff gear oil fill question

KrackaC8

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Quick question that my [lacking?] Google & Gemini abilities haven't been able to answer:

For the differential fluid, is there enough clearance to use the EZ squeeze pouches (Valvoline & Amsoil) to fill or am I better off with a traditional bottle + pump?

I plan to do that along with transmission fluid in fairly short order.
 

offizial

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There’s hardly any back there just did mine and used the slippery pete. You might be able to fit the flex bottles back there but it would be close.
 
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KrackaC8

KrackaC8

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There’s hardly any back there just did mine and used the slippery pete. You might be able to fit the flex bottles back there but it would be close.
Thank you
 
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KrackaC8

KrackaC8

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Ok yeah I just got under there... No chance the bags fit; pump it is. Just picked 'er up this afternoon to be the new weekend toy!

Yellow 2023 with only 500 miles on it.
 

offizial

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Ok yeah I just got under there... No chance the bags fit; pump it is. Just picked 'er up this afternoon to be the new weekend toy!

Yellow 2023 with only 500 miles on it.
That’s early to be doing it but I understand. I really don’t like how Nissan specs “only non synthetic” for the rear diff.. been trying to understand why but can’t find a good conclusion other than them cutting cost. I put in RP 75-90 for now.
 
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KrackaC8

KrackaC8

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That’s early to be doing it but I understand. I really don’t like how Nissan specs “only non synthetic” for the rear diff.. been trying to understand why but can’t find a good conclusion other than them cutting cost. I put in RP 75-90 for now.
Appreciate the thoughts. I do plan to give it a bit to break-in the gears on the factory conventional fluid. Just in the planning stages at the moment. I plan to go with Redline 75W-90 in the diff and MT-85 in the tranny (been running their stuff for 25 years and always love how their transmission fluid performs). Their gear oil is fine too, have it in our Wrangler, but running Amsoil in the Grand Cherokee since Redline was backordered at the time due to their CA to TN relocation. Was actually tempted by Valvoline's new EP gear oil had the bags fit!

Some LSD manufacturers still spec conventional gear oil in the Jeep world too, but even so I'd rather run a better oil that utilizes a robust addictive package. I did actually run conventional 90W in my S2k and Evos back in the day when everyone else was jumping on the Amsoil bandwagon.

Car now has 700 miles on it and I was able to get the infotainment software and navigation maps updated this evening.
 
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Who.Am.Eye.2716

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Ok yeah I just got under there... No chance the bags fit; pump it is. Just picked 'er up this afternoon to be the new weekend toy!

Yellow 2023 with only 500 miles on it.
What setup would you be using to refill the diff and trans?

This will be the first for me and want to be sure to use the right tools
 
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KrackaC8

KrackaC8

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What setup would you be using to refill the diff and trans?

This will by the first for me and want to be sure to use the right tools
I'll get a gallon jug of each fluid plus a fluid pump for each. I typically get my pumps from Harbor Freight but it appears Summit Racing has the same ones at the same price:

1000005028.webp
 

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That’s early to be doing it but I understand. I really don’t like how Nissan specs “only non synthetic” for the rear diff.. been trying to understand why but can’t find a good conclusion other than them cutting cost. I put in RP 75-90 for now.
This is to allow the clutch type diff to work, most synthetic is too slick and you will basically have an open diff if you use it or get weird problems like chatter. It's been like this since the 90's, many cars will even have a metal tag on the diff saying to only use LSD compatible gear oil/non-synthetic.

Most of Redline's product line contains friction modifiers for limited slip diffs already just read the bottle/website to make sure, and if you still get chatter you can add a bit of their stand alone friction modifier to fix it. Note that adding too much will effect lockup.
 

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When using the squeeze bag lube all you have to do is put a tube on it and your GTG.
 
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KrackaC8

KrackaC8

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When using the squeeze bag lube all you have to do is put a tube on it and your GTG.
Exactly how I did my Grand Cherokee front differential with the Amsoil packs.
 
 






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