Front Diff and Transfer Case Oil Change Howto

not sure how my 2015 transfer case compared to the 2023, but it was so clean at 60k, i knew that was the last time i would service it barring unforeseen issues. And, i plowed with that and lived in the rust belt.

 

100%! I'll look at the TC again at 90K. The oil looked new. Lesson learned!

 

Think I’m going to get on the habit of doing it yearly, bit overkill but the way I see it, cheap insurance. Think my biggest mistake was never changing the oil in diffs and transfer case with, it’s a 2013, and owned since 2016. Probably a big reason why my rear differential went, all the weight, 35” tires and then topped it off with a S/C.



Next year’s oil change, definitely replacing the front diffs with the Lexus drain and fill plug.

 

Just saw this thread and reminded me to check when it was done. Bought the 2105 V6 4x4 back in January with 185k miles, the Carfax said the F&R diffs oil was changed at 100k miles, nothing listed for the transfer case. Will be doing all 3 next week since I'm almost to 200k miles now. Will probably do the diffs every 30k miles from here on out and the TC at 50k. Amazon has a nice deal on a M1 six pack here~

$70 Mobil1 1043611 Full Synthetic Gear Lubricant, 75W-90 Quart 6 PK

https://www.amazon.com/dp/B09QS1J14P

 

smart move with the lexus plug. ebay had them OEM and decent deals when i got mine 6 mos ago

 

I've seen a few in this thread mention using a special fluid in the TC. But.... Do we need to worry about that at all? If a gl4 transmission fluid would be better for the life of the TC, I'd rather use it. But our manual states 75w90 gear oil for the TC. And if it makes zero difference either way or the gear oil is better, that's what I'll use.
The 3rd gens got the new 75wLF TC fluid. Is that because they decided that was a better fluid, or did something physically change w/ the TC?

 

These trucks seem to do pretty well just going by the manual, 75w90 for me! And since that "new" TC oil is about $100 per liter, no thanks!

 

Yeah, that new stuff is expensive.. But if you can see from my forum pic, my truck is not stock anymore.. Actually weighs over 7k lbs fully loaded for a camping trip. And, I want it to last forever because building a new rig at my age probably isn't ever going to happen. (Took me 10 years to build this one out to where it is now.. Been a fun journey). So if the new fluid were better in the 2nd gens as well as the 3rd, it would be worth it to me. I'm just having a hard time figuring out if anything physically changed w/ the TC, or if they simply started recommending a different fluid.

Probably better to get new fluid in either way, though, and if the manual says it's ok... I should believe it's OK.

 

Just did all three gear oil changes today, I did the front diff w/ a helper. Had a hose that I ran through the engine bay and the wife got the bottle on top and gravity fed down to the diff fill hole, easy-peasy. And they weren't kidding about 6 qts. drained out just a bit under that, and exactly the same went in. That front diff drain plug really popped when it broke free, glad I was able to use my leg for leverage, getting old sucks

 

6 quarts between the 3, right?

 

Yes sir.

 

Thanks for the how to this will come in handy when it’s time for mine.