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Differential oil change

CarbonSteel

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pity they don’t have this deal on the non-Synthetic; Eaton doesn’t recommend Synthetic for the TruTrac, so i just use Dino juice in both pumpkins.
Why?
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CarbonSteel

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Does anyone you thread sealer on the drain and fill plug? My dealer said it’s not needed as long as it’s torqued down.. said they never have issues…thoughts?
Yes, but more from a lubrication standpoint given the plugs are tapered thread and there is zero pressure on them.
 

SadRobot

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Does anyone you thread sealer on the drain and fill plug? My dealer said it’s not needed as long as it’s torqued down.. said they never have issues…thoughts?
I use yellow plumber's tape. That being said when I removed mine this time the shop that had done the previous diff oil change with the re-gear hadn't put anything on them. I never had any leaks or anything though.
 

zouch

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i'm sure someone is going to say "i used Synth in my TruTrac without any problems", but considering that the TruTrac is a gear-driven LSD, Eaton probably feels safer recommending Dino because there are fewer variables that might adversely affect the torque biasing.

from Eatons current Q&A FAQ:
"What type of lubricant should I use in my Detroit Truetrac?
We recommend that a quality, petroleum-mineral based, GL5-rated gear oil be used. Friction modifiers should not be used because they will decrease performance (reduce differential bias)."

reasons *why* seem to be mostly hearsay at this point; word is that Eaton reps have called Synthetics "too slippery", and made other comments about how Synthetics vary so much they can't test them all and therefore just don't recommend any.
whether or not Synthetics are tolerable, their statements over the years have been consistent about NOT using Limited Slip Friction Modifiers (which many Synthetics include). there are some Synthetic Lubes now that don't include Friction modifiers (Red Line, for example) so if i were to feel the need to use Synth i would probably use one of those, but until then i'll just use what the manufacturer recommends and make sure it stays clean.


 

DanW

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I got under the front diff of the '21 Gladiator and......there is a drain plug! Glad it's there, but that now means it will need protection in the form of either a Rancho diff skid or I saw another diff cover with a piece welded on that goes under and protects the plug.

I'll be changing the diff fluid out on both ends tomorrow!
 

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CarbonSteel

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i'm sure someone is going to say "i used Synth in my TruTrac without any problems", but considering that the TruTrac is a gear-driven LSD, Eaton probably feels safer recommending Dino because there are fewer variables that might adversely affect the torque biasing.

from Eatons current Q&A FAQ:
"What type of lubricant should I use in my Detroit Truetrac?
We recommend that a quality, petroleum-mineral based, GL5-rated gear oil be used. Friction modifiers should not be used because they will decrease performance (reduce differential bias)."

reasons *why* seem to be mostly hearsay at this point; word is that Eaton reps have called Synthetics "too slippery", and made other comments about how Synthetics vary so much they can't test them all and therefore just don't recommend any.
whether or not Synthetics are tolerable, their statements over the years have been consistent about NOT using Limited Slip Friction Modifiers (which many Synthetics include). there are some Synthetic Lubes now that don't include Friction modifiers (Red Line, for example) so if i were to feel the need to use Synth i would probably use one of those, but until then i'll just use what the manufacturer recommends and make sure it stays clean.
I suspected "synthetic is too slippery" as the reason and most synthetics have FM in them as you said. More key to long axle life is frequent/consistent oil changes versus the oil itself. 85W-140 is one of the most "durable" gear oils out there, but does not work well in cold climates, so 75W-140 typically gets the nod in its place.
 

Rhinebeck01

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Does anyone you thread sealer on the drain and fill plug? My dealer said it’s not needed as long as it’s torqued down.. said they never have issues…thoughts?
Teflon Tape applied to both the fill and drain plug is a very positive thing to do..

The Teflon Tape aides in the seal but equally or more importantly.... is an add that will help keep the plug from freezing up over time/then the plug hard/or impossible to remove in the future.
 

SadRobot

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pity they don’t have this deal on the non-Synthetic; Eaton doesn’t recommend Synthetic for the TruTrac, so i just use Dino juice in both pumpkins.
Since you brought up synthetic... I just filled both diffs with Synthetic 75W-140 Valvoline that has an additive and now I'm wondering if that is bad for my ARB air lockers.
 

grimmjeeper

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Since you brought up synthetic... I just filled both diffs with Synthetic 75W-140 Valvoline that has an additive and now I'm wondering if that is bad for my ARB air lockers.
Doesn't hurt the ARB. Doesn't really hurt anything. Eaton doesn't recommend it in the Truetrac because it affects torque bias. But that's about it.
 

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DanW

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Both diffs drained and filled with Valvoline 75w140! I used teflon tape on the threads, too!

Jeep Wrangler JL Differential oil change PXL_20231119_185906031
 

OldGuyNewJeep

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Both diffs drained and filled with Valvoline 75w140! I used teflon tape on the threads, too!

PXL_20231119_185906031.jpg
I can smell this picture.
 

Trojan_Actual

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Plan on doing my differentials and T/C here soon. I wanna pull the diff covers off to inspect/clean too. What's the toque on the bolts? And do I need to replace bolts?
 

ErAcEr

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