Driveline fluid changes (x-mission, t-case & diffs)

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brickbox
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Driveline fluid changes (x-mission, t-case & diffs)

Postby brickbox » Sun Feb 09, 2020 9:01 am

Had a slightly warm bout of weather yesterday. So I decided to get the ATF drain and fill and t-case fluid changed.

I need to get the rear and front diffs done as well.

I had a few questions and I would really appreciate some clarity on them:
1. Amount of trans fluid - the was fluid was changed about 5 years and 65k miles ago. I used 4.1 quarts of Valvoline Maxlife ATF. The car shifts nice and smooth. After a warm up, the ATF is nice and red and it shows up on the hot side of the dip stick, coloring about 4 of those “diamond†marking they have on the dip stick. So question is: do I need to add some more or am I good? If I need to add more, how much is the fluid amount to go from bottom to top of that diamond marked area on the hot side of the dip stick?

2. T-case: 100k miles old original t-case fluid. It was DISGUSTING. The drain plug magnet actually had a quite bit of metal filings! Glad I changed it. Again, Maxlife atf. Now I did not do a flush. I just drained it all out. Closed the drain plug and filled in from the fill port till the fresh ATF was dripping out. Any issues with this? Do I need to change the fluid again soon or can I wait 40k miles? I was planning on doing trans and t-case again in 40k miles.

3. Diff cases - haven’t gotten to these yet. 1. Do our rear diffs have LSD? If so, do I need to get a special additives package of some sort? I have a quart of Lucas 75w90 from a previous vehicle’s project. So I was planning on just getting another quart of the SuperTech full synthetic in addition to the Lucas. Any problems with this approach? Or should I stick to Mobil1 Full synethetic with the LS package?

4. Front diff - the owners manual states 80w90. I have a quart of the LubroMoly 80w90 synthetic from another vehicle’s project. So can I just use the left over of the Wally Synethic 75w90 for the rest of the amount?


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smj999smj
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Postby smj999smj » Sun Feb 09, 2020 1:08 pm

1-The crosshatched area on the ATF dipstick represents about 1-qt. If the fluid is warmed-up and the vehicle is on a level surface with the engine idling, the fluid level should be at the top of the crosshatched area. I would add 1-pint at a time and recheck the level after each pint until it's full.

2-Drain and fill of the transfer case is fine. I use Maxlife ATF, as well, replacing around every 50-60,000 miles.

3-The front and rear axles have open diffs with electronic LSD. It uses the ABS system to lock the spinning wheel, applying power to the wheel with traction. You don't need any LSD additives. The rear diff specifies synthetic 75W90. The front diff specifies conventional 80W90 gear oil, but if you want to substitute synthetic 75W90 in its place, that will be fine (it's what I use in mine). While it will most likely be perfectly fine, personally, I don't like mixing two different brand fluids.

brickbox
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Location: Rust Belt

Postby brickbox » Sun Feb 09, 2020 2:54 pm

Thanks for the response smj. What are your thoughts on Supertech?
I saw your old posts where you recommended it. Is it still running good on your R51s?

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smj999smj
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Postby smj999smj » Mon Feb 10, 2020 1:41 am

Yes, still using Supertech full-synthetic 5W30 in my Pathfinders.

brickbox
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Location: Rust Belt

Postby brickbox » Wed Feb 12, 2020 4:00 am

I ended up doing the rear diff. Might be my implicit bias, but i feel like
the trucks rides smoother with the new atf and rear diff fluid, especially when taking off stop lights. Ended up using Mobil 1 75w90.
The old fluid that came out had an odd green tinge when held against light.

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smj999smj
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Postby smj999smj » Thu Feb 13, 2020 1:02 am

I've seen the "green tinge" you are referring to in gear oil; it's perfectly normal.


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