Rear gear oil

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RHanna

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I recently purchased a 2wd 2010 1500 and I'd like to change the diff fluid. According to the build sheet for my VIN I have the 3.92 with anti-spin. So the manual calls for Mopar 75w-140 and the Mopar friction modifier.

I believe there are other oil brands such as redline, Valvoline, amsoil that's just as good as the Mopar brand. My question is, do I still need to add the 4 ounces of friction modifier when most of these other brands list a friction modifier already in their synthetic oil?
 

Burla

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I wouldn't use Mopar gear fluid if you gave it to me free.

No, all modern gear fluids contain the modifier, you have to actually special order fluids if you DONT want it. Now, sometimes you may have shudder or chatter, in that case you add one ounce at a time till it goes away. Amsoil is nice, they have bags now so you don't need a pump. I think it takes 2.75 quarts if memory is serving me correctly. It is eaither 2.75 or 3,75 quarts, so chck that, I know it is one of them. If the gear fluid says multi-purpose or anything like that with LS in title, then is contains the modifier. Even if the title doesnt say it, it will likely just say that it does contain modifier. Buy amsoil from amsoil, on amazon they charge too much. If not amazon, redline, m1, or valvoline all good choices. RP, Lucas, Mopar bottom of the heap in independent testing, been posted here a lot.
 

1999 White C5 Coupe

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I wouldn't use Mopar gear fluid if you gave it to me free.

No, all modern gear fluids contain the modifier, you have to actually special order fluids if you DONT want it. Now, sometimes you may have shudder or chatter, in that case you add one ounce at a time till it goes away. Amsoil is nice, they have bags now so you don't need a pump. I think it takes 2.75 quarts if memory is serving me correctly. It is eaither 2.75 or 3,75 quarts, so chck that, I know it is one of them. If the gear fluid says multi-purpose or anything like that with LS in title, then is contains the modifier. Even if the title doesnt say it, it will likely just say that it does contain modifier. Buy amsoil from amsoil, on amazon they charge too much. If not amazon, redline, m1, or valvoline all good choices. RP, Lucas, Mopar bottom of the heap in independent testing, been posted here a lot.


What is wrong with Mopar gear fluid? Are you also unhappy with the Mopar anti-slip additive (which is gear fluid also)?
 

Burla

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What is wrong with Mopar gear fluid? Are you also unhappy with the Mopar anti-slip additive (which is gear fluid also)?
study

Even though that study is old, it shows how little care goes into approving a fluid and getting the mopar name. The issue is it is always changing, but not for some staple gear fluids such as m1 or valvoline which have always been good, redline and amsoil as well. Those go the extra mile, m1 for otc or amsoil for boutique. Now, Mopar is most likely a Pennzoil clone, but also those didnt test well. I prefer to buy real quality if I can. Being on the 4x4 forums from way back since the beginning of the internet, two of the bottom three on the list are straight cus words on those boards from the amount of gear fails they are suspect in. In a truck application, I believe it matters way more then anything else. just my opinion...

I doubt the mopar additive is different then most others, but personally I would still use something else.

I just posted a favorable review on maxpro a mopar brand, because that formula looks good. I call it how I see it, on gear fluids I have NOT seen anything good from them. It is possible even Pennzoil is in the same quality as the other two otc currently, but their track record is still relevant, would you rent your house to a convicted felon if the other potential renter isn't a felon? m1 gear oils are even more standout then their engine oils.
 
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HEMIMANN

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I wouldn't use Mopar gear fluid if you gave it to me free.

No, all modern gear fluids contain the modifier, you have to actually special order fluids if you DONT want it. Now, sometimes you may have shudder or chatter, in that case you add one ounce at a time till it goes away. Amsoil is nice, they have bags now so you don't need a pump. I think it takes 2.75 quarts if memory is serving me correctly. It is eaither 2.75 or 3,75 quarts, so chck that, I know it is one of them. If the gear fluid says multi-purpose or anything like that with LS in title, then is contains the modifier. Even if the title doesnt say it, it will likely just say that it does contain modifier. Buy amsoil from amsoil, on amazon they charge too much. If not amazon, redline, m1, or valvoline all good choices. RP, Lucas, Mopar bottom of the heap in independent testing, been posted here a lot.

Except for Mobil Delvac 1 Gear Oil & Red Line NS Gear Oil.

I'm using Mobil Delvac 1 in my AAM Truc Trac Torsen Diff
 

FullForceRam

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Considering all of my 3 RAM trucks I've owned since 2002 ( 2 of which had well over 300K miles on their backs) have all run on Mopar oils, I've never had a reason to go with other brands. I'm sure Amsoil, Mobil 1, Redline are also good oils. Comes down to preference really.
 

ilovemyramlaremie

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No to hijacked this thread, but in in the same boat regarding the rear gear oil. I was doing research on line to see what oil weight was recommended for my 2010 Ram 1500 laremie 4x4. I have the 12 bolt rear, but not sure what gears I have. Some sites was saying 75/90 some were saying 75/140 full synthetic.
What you guys been using on your 4x4 trucks. Thanks
 

Burla

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No to hijacked this thread, but in in the same boat regarding the rear gear oil. I was doing research on line to see what oil weight was recommended for my 2010 Ram 1500 laremie 4x4. I have the 12 bolt rear, but not sure what gears I have. Some sites was saying 75/90 some were saying 75/140 full synthetic.
What you guys been using on your 4x4 trucks. Thanks
2010 1600 = 75w140 for whatever gears you have in the rear, 90 weight in the front.
 

MontanaHandyman

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study

Even though that study is old, it shows how little care goes into approving a fluid and getting the mopar name. The issue is it is always changing, but not for some staple gear fluids such as m1 or valvoline which have always been good, redline and amsoil as well. Those go the extra mile, m1 for otc or amsoil for boutique. Now, Mopar is most likely a Pennzoil clone, but also those didnt test well. I prefer to buy real quality if I can. Being on the 4x4 forums from way back since the beginning of the internet, two of the bottom three on the list are straight cus words on those boards from the amount of gear fails they are suspect in. In a truck application, I believe it matters way more then anything else. just my opinion...

I doubt the mopar additive is different then most others, but personally I would still use something else.

I just posted a favorable review on maxpro a mopar brand, because that formula looks good. I call it how I see it, on gear fluids I have NOT seen anything good from them. It is possible even Pennzoil is in the same quality as the other two otc currently, but their track record is still relevant, would you rent your house to a convicted felon if the other potential renter isn't a felon? m1 gear oils are even more standout then their engine oils.
Holy mackerel...am I glad you posted that study! I recently swapped out my front diff fluid with some Lucas 75/90 I had hanging around. Gonna order some Amsoil and get rid of that Lucas garbage as soon as I can.
 

Jeepwalker

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I use Walmart synthetic. Inexpensive, works well, easy to find. Plenty of guys on other forums use it. Been using it since the 90's in various vehicles. And in manual trannys. I've had so many vehicles get up and over 250k-275k till they pretty much rust out. One Jeep grand cherokee ran up over 300k (probably 325) till it rusted out. It's in all my current vehicles' diff's now. It's just easier to keep track of what's in each vehicle when I've standardized on one lube. I do regular changes, maybe every 30k-40k mi. I'm sure someone somewhere can produce a paper where it didn't 'test well'. But personally it's worked fine for me, and I know my own results.

I wouldn't hesitate to put Mopar lube in my truck's diff. Or any name brand dino or synth lube. If I was towing large loads constantly, I might consider a boutique brand, but, C'mon, how often do rear ends fail in normal duty using approved lubes? Use a suction gun or a hose on the bottle to install.

Cheers!
 
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RHanna

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No to hijacked this thread, but in in the same boat regarding the rear gear oil. I was doing research on line to see what oil weight was recommended for my 2010 Ram 1500 laremie 4x4. I have the 12 bolt rear, but not sure what gears I have. Some sites was saying 75/90 some were saying 75/140 full synthetic.
What you guys been using on your 4x4 trucks. Thanks
Try this website with your vin

 

hooterz

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Just did the rear diff on my 2005 Ram 4x4 with 60k miles, I used Royal Purple and even though it says it has friction modifier in it, I also added a bottle from MOPAR. I also added the B&M diff cover for easier gear oil changes. I need to do the front diff next, I wish there was an aftermarket cover for my 2005.
 

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Harley Harrold

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I don't have limited slip at this time, but I run Lucas synthetic 75w140 oil in my 3.92 differential.

75W140GearOil_800x950.jpg
 

Mister Luck

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The point with differential fluids and transaxle fluids in 4x4s

Is your temperature range and the classification approval ratings
You want G-5 quality rating and best temperature rating using the factory specific recommendations for your model and date of manufacture.

Amsoil is probably one of the best manufacturers of lubrication fluids but there are other that are similar.

If you sign up for Amsoil’s emails you’ll get notifications of when they offer free shipping, which is only two the three times a year.
 

KLook

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That study was interesting and I have been an Amsoil fan since it came out. I will change mine over.
 
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