Changing Differential & Transfer Case Fluids - Pics Included

I did mine the other day at 45k miles. I removed rear skid pan and repainted it and said might as well check the front one while at it. Was surprized at how rusty the very front skid pan was! A thick center "bumper" piece was covered in thick rust. Had 2 rusted thru holes once I cleaned it up - I'm in Virginia not upstate NY! Seems I have lots of surface rust on frame. Never been off road or on the beach either.
 
Big thanks to G.I.G. we/he got mine done over the weekend. This is a good maintenance task to complete on a Saturday. We grilled some burgers, drank some beers and enjoyed the weather. This is a messy job that is for sure, my neighbor found out when his white dog jumped in the pan filled with oil, he’s no longer white.

I went with M1 synthetic 75w-90 and I can definitely tell a difference. She rides smoother especially on those braking to a red light then gassing it once it hits green. I can’t wait till the snow starts falling since ive heard less binding occurs in 4wheel.

Cost was $8.99/qt and I purchased 7. I believe the washers were about $9 for all of them [the guy working the parts dept gave me the wrong one so we re-used the fill washer on the transfer by flipping it over. I only have 38k on my truck] a pump was $9. Omaha Steak Burgers and beer...I can’t remember.

Next maintenance item will be the plugs.
 
...
transfer case drain plug 90341-18006
Transfer Case Fill Plug 90341-18006
...

Rear Differential drain plug 90341-18057
Rear Differential Fill Plug 90341-18006
...

Just did this service for the second time. Used Mobil 1 then and now. Not sure if I can "describe" the look of the used syn oil as any different than the first dino OEM oil drain other than it didn't smell as bad. Had to clean just a small accumulation of sludge off the magnets. Had ~136K Km on it.

Not sure why I didn't notice this the first time but it struck me as odd that the transfer case drain plug didn't have a magnet. Thought it might have come loose (not likely for a magnet) because even the fill plugs have a recess for the magnet that isn't there. Found in this thread that the transfer drain and fill plugs are the same part so I'm relieved I didn't lose it inside the case. Also, the diff fill plug is the same part. The diff drain plug is the same except with a magnet.

I know the transfer case is aluminum but my question is why didn't Toy use a magnetic plug? Did they just cheap out? There are steel gears and chain inside. Would it hurt to use a magnetic plug?
 
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Changed my front and rear diff and transfer case today. I used Mobil 1 75W-90 for all three and it is a huge improvement from what I had before.

I'm at 86k miles (2005 V8) and the dealership I bought it from has no record of these fluids ever being changed, so I just assume that they have never been changed in the vehicle's history :dammit:.

First and foremost, the fluids from all three were disgusting. The front and rear drain plugs had a ton of sludge on the magnet and was coming out like thick goop that was not of a uniform consistency. The transfer case was the cleanest of the three, but that's not saying much. The lube from the transfer case was opaque black/brown/grey colored.

This was a pretty easy task and the truck drives noticeably better now. I took it for a spin after everything was done and it is driving MUCH smoother, especially when making U-turns, turning in reverse, and making other sharp turns.
 
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Changed my front and rear diff and transfer case today. I used Mobil 1 75W-90 for all three and it is a huge improvement from what I had before.

I'm at 86k miles (2005 V8) and the dealership I bought it from has no record of these fluids ever being changed, so I just assume that they have never been changed in the vehicle's history :angry:.

First and foremost, the fluids from all three were disgusting. The front and rear drain plugs had a ton of sludge on the magnet and was coming out like thick goop that was not of a uniform consistency. The transfer case was the cleanest of the three, but that's not saying much. The lube from the transfer case was opaque black/brown/grey colored.

This was a pretty easy task and the truck drives noticeably better now. I took it for a spin after everything was done and it is driving MUCH smoother, especially when making U-turns, turning in reverse, and making other sharp turns.

Nice.

Did mine yesterday. I used Royal Purple in the rear and mobil 1 for the center.

The rear was pretty nasty, but not much sludge on the magnet. The transfer case looked pretty good.

I didn't have time to get the front skid off, so next weekend I'll do the front differential.

I thought it drove more smoothly, but it could have been in my head.
 
Is it safe to use limited slip type fluid in my differentials and transfer case?

I bought Mobil 1 for limited slip. Is that OK to use?

As long as it says API GL-5 Limited Slip 75W-90

You know more than the dealership employees, so I figured I would ask you! Is it safe to use limited slip type fluid in my differentials and transfer case?
I have a 2005 Canadian T4R Limited V6 Part time 4WD. I just did a front and rear diff fluid drain and fill as well as a transfer case fluid drain and fill with "Mobil 1 for limited slip" and it is "API GL-5 Limited Slip 75W-90". I called 2 dealerships and had my VIN # handy but they could not tell me if I had a Limited slip diff or not or if I needed a limited slip type fluid.

The first dealership said to look on the diff for a sticker above the drain plug, if it has a sticker it has a limited slip diff and if there is no sticker it is not a limited slip diff. The second one said to look for vacuum or electrical lines on the passenger side of the diff, if those are present it is a limited slip diff. From memory, all my owners manual says is API GL-5 75W90 gear oil. I want the best for my truck, we all do. Should I drain the differentials and transfer case and fill with a non limited slip type fluid?

Do I have a limited slip differential in my truck in the front and/or rear?
Did my trim of T4R come with one type of diff? Was another type of diff optional?
Can I tell by looking at my diff?
Is it safe/recommended to use this limited slip fluid in a Non-limited slip diff? if so, why?
Is it safe/recommended to use this limited slip fluid in my transfer case? If so Why?

Thanks!
 
2005 V6 4WD Runners have limited slip diff. You can use LS fluids in transfer case because it calls for same 75w-90 weight (LS additives wont hurt anything).
 
Changed all mine today!!!

Rear Dif: With the spare tire out I had no problem refilling right out of the bottle.

Transfer Case: A 6" piece of clear tube with a clamp to the nozzle on the bottle and it worked just fine.

Front Dif: Here I used a 3' section of tube and my able bodied assistant, my wife! I held the tube in place, she squeezed the bottle and I was done in no time.

The hardest part was getting the bolts out of the front skid plate, just a little rusted.

One other tip: A 15/16" socket works as well as the 24mm!

Used Mobil 1 in all three...
 
Definitely a helpful thread. Thanks for putting it together! While changing out these fluids certainly isn't the most complex thing to do, having some pictures saved me the time of figuring it out on my own using my electronic service manual.
 
This is an AWESOME thread. Gotta love a good write-up with lots of pics :) I have 51,000 miles and I don't think it's ever been done on mine :/ Planning to switch all three to Mobile 1 as soon as it's not blistering cold outside. Thanks to the OP and to those who supplied the various parts numbers.

I have what might seem like a dumb question that relates to this topic. Is the center differential located within the transfer case itself? I'm assuming so. You never hear mention of it when talking about other fluid changes. I did search the forum and couldn't find an answer to my question haha.
 
Great write-up and details.

I didn't see this mentioned, but ALWAYS remove the fill plug FIRST before draining the diffs. If the fill plug doesn't come off, stop there. You don't want to find yourself stranded on the driveway because the diff(s) have no oil in them.

:iagree:

Which one to use 75W-140?
http://www.mobil.com/USA-English/Lu...bil1_Synthetic_Gear_Lubricant_LS_75W-140.aspx
-VS-
75W-90?
http://www.mobil.com/USA-English/Lubes/PDS/GLXXENPVLMOMobil1_Synthetic_Gear_Lubricant_LS_75W-90.aspx
 
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