What fluid should I use in the Transfer Case/PTO?

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Bullitt5094

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I am about to do the first change in the Transfer case (PTU?) on my 2016. I'm sure there is a fluid recommendation in the OM but is there a recommendation of any superior gear oil from the experienced users on the forum? Any suggestions would be greatly appreciated.
 

Joshw0000

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What I use:

RDU - Royal Purple 75w90
PTU - Royal Purple 75w140

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Ive heard motorcraft is a safe bet, RP is always a good choice from a solid company, but I second @SM105K suggestion, he wrote the Bible on maintaining these cars. Myself and others have felt a noticeable difference in the car with the lightweight shockproof.

I have no experience with any other fluids to compare and while we use different fluids, we all agree the service interval is the most important with what ever fluid you use. Have fun, and if it's not a PP car remember to breathe.
 

Bullitt5094

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Have fun, and if it's not a PP car remember to breathe.
Mine is not a PP car so I'm a bit puzzled at this response.
Also is there a good source for the Redline that SM105K is recommending? I don't see it on Amazon. And what is the capacity of the transfer case? If there is another thread covering all of this, I haven't found it so sorry if this is all redundant for the forum.
 

FREAK_SHO

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Mine is not a PP car so I'm a bit puzzled at this response.
Also is there a good source for the Redline that SM105K is recommending? I don't see it on Amazon. And what is the capacity of the transfer case? If there is another thread covering all of this, I haven't found it so sorry if this is all redundant for the forum.
Mad -scientist's way of sayin' the non PP PTU is not quite as "easy" as the PP PTUs
 
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Mine is not a PP car so I'm a bit puzzled at this response.
Also is there a good source for the Redline that SM105K is recommending? I don't see it on Amazon. And what is the capacity of the transfer case? If there is another thread covering all of this, I haven't found it so sorry if this is all redundant for the forum.
It's been covered but I too have a non pp car and have recently done this for the first time myself. The pp cars have a drain plug, the non pp cars only have a fill plug which means you have to suck the fluid out of the case which can be frustrating and time consuming (hence the breathe comment). It is recommended to use a vacuum pump, I used one that I used for brake bleeding, same thing literally. Some prefer the syringe method but what ever you prefer.

Can't say for sure on capacity but 1 bottle will probably do the trick since you won't be able to get it all out. Usually it's recommended to pump out as much as you can, run it for a few miles, and repeat 3 times, this gives you almost fully fresh fluid.

As for a reliable source for lightweight shockproof, I'm told it's a smaller company and it's not always easy to find. I suggest when you do find it get 4-6 to have some stock.
 

Zpak

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Non PP without drilling and tapping a drain plug you have to suck out the fluid and pump back in through the fill plug.

As for fluid, redline lwsp all day. Smooth as silk.
 

Joshw0000

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Things you'll need:

A way to get the car off the ground. I like to use ramps in the front, jack up the back, and put stands under the back. Try to get it as level as possible.

Lots of socket extensions (unless you remove the front right tire) to get to the PTU fill plug. See the above comment for why I do it this way. Harbor Freight for the win.

A low profile ratchet to get to the tight space to remove the RDU plug (or cut off the unused exhaust bracket). Harbor Freight also has a cheapo that works.

A fluid extractor. Something like this works great - Wzyblixo 6.5L Oil Extractor - Pneumatic/Manual Vacumm Fluid Extractor Fluid Change Pump with Extended Oil Suction Hose and A Brake Bleeding Hose for Automotive Fluids Vacuum Evacuation https://a.co/d/g26qh5A

A pump to push the gear oil back into the PTU / RDU. Something like this is good - Slippery Pete 5cc Hand Pump Transfers Gear Oil, Transmission and Differential Fluids From Quart Bottles (Not for Red Line Quarts) (1) https://a.co/d/2hLGlGk

These are just random links I found on Amazon for reference. You can use better or cheaper pumps.

PTU - one quart is fine, RDU calls for 38.4 oz. As mentioned, you won't get the full amount in or out so one quart should be fine as well. Suck out all you can, fill until it overflows and put the plug back on with a little bit of thead sealant.

If needed, I'll see if I can find an old post from my first change.

Oh yea, you can always get Royal Purple on Amazon.


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Bullitt5094

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OK. That makes sense. Maybe I'll drill and add futomo valve in there as I have in several places on my 6.0 Powerstroke. I did purchase one of these Thing that sucks so that should work if i don't go the additional drain hole route. And I do have a two post lift so working under the car is a LOT easier.
 

Bullitt5094

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Things you'll need:

A way to get the car off the ground. I like to use ramps in the front, jack up the back, and put stands under the back. Try to get it as level as possible.

Lots of socket extensions (unless you remove the front right tire) to get to the PTU fill plug. See the above comment for why I do it this way. Harbor Freight for the win.

A low profile ratchet to get to the tight space to remove the RDU plug (or cut off the unused exhaust bracket). Harbor Freight also has a cheapo that works.

A fluid extractor. Something like this works great - Wzyblixo 6.5L Oil Extractor - Pneumatic/Manual Vacumm Fluid Extractor Fluid Change Pump with Extended Oil Suction Hose and A Brake Bleeding Hose for Automotive Fluids Vacuum Evacuation https://a.co/d/g26qh5A

A pump to push the gear oil back into the PTU / RDU. Something like this is good - Slippery Pete 5cc Hand Pump Transfers Gear Oil, Transmission and Differential Fluids From Quart Bottles (Not for Red Line Quarts) (1) https://a.co/d/2hLGlGk

These are just random links I found on Amazon for reference. You can use better or cheaper pumps.

PTU - one quart is fine, RDU calls for 38.4 oz. As mentioned, you won't get the full amount in or out so one quart should be fine as well. Suck out all you can, fill until it overflows and put the plug back on with a little bit of thead sealant.

If needed, I'll see if I can find an old post from my first change.

Oh yea, you can always get Royal Purple on Amazon.


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This is very helpful. Thanks! You were posting this as I was posting the reply above.
 

Joshw0000

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This is very helpful. Thanks! You were posting this as I was posting the reply above.
No prob. You have a lift so you can ignore half of what I said, lol I'm sure you're fully capable of doing this service.

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kryptto

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1733231369843
 

Bullitt5094

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What you show linked there is not the Shockproof Lightweight oil I thought everyone was describing. Isn't this what I should use in the transfer case? I want to be sure I'm attempting to track down the correct product. Redline Oil
 

kryptto

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What you show linked there is not the Shockproof Lightweight oil I thought everyone was describing. Isn't this what I should use in the transfer case? I want to be sure I'm attempting to track down the correct product. Redline Oil
thats it - however there are threads where redline has been out of stock for a while. nothing wrong using the what's right for my car, and using a product in stock. unless someone posting here can suggest a redline product not out of inventory

PS - I sent an email to the company - lets see what they say, will report back once I hear from them.
 
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Bullitt5094

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I certainly can't find it. I'm likely to get RP and make this initial change since I can grab it today. I'll run that for a while and just change it again with the RL if I can find it. The car is @ 70K so I'm thinking it's overdue from what I've recently learned here.
 

Joshw0000

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Yep, it needs to be done but you're not in too bad shape. You can do your next change in 15K miles, then go to 30K miles after that.

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kryptto

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I certainly can't find it. I'm likely to get RP and make this initial change since I can grab it today. I'll run that for a while and just change it again with the RL if I can find it. The car is @ 70K so I'm thinking it's overdue from what I've recently learned here.
35/k miles - it will look like graphite grey - make a change 15k later, then every 30K
 

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