Transfer Case Needs vs. Differential Needs

[kyoo]

In GENERAL,

Are there any needs that a transfer case would have that a typical differential (let's say clutch type) would not have? I believe in general, the differential may want some limited slip additives that a transfer case would not necessarily need, but other than that?

 

[abycat]

well some transfer cases take atf not gear oil so its kinda hard to compare the two. But besides that im not really to sure.

 

[LeakySeals]

Depends on type of transfer case, its function, and its fluid. For example my Escalades diffs have synthetic gear oil. The TC uses Dex III dino. So the TC needs to be changed more often.

 

[meep]

many T-cases roll a chain. if used often I'd change it more frequently than a diff.

different animals to me. and many diff kinds of t-cases, so hard to make generalizations.

 

[kyoo]

hmm thanks for the input guys. I think i'll use lightweight shockproof in the transfer case and just 75w90 in the rear

 

[supton]

Hard to say. I think my transfer case is a chain--but since the chain doesn't turn in 2WD, it's quite easy on the oil.

My front diff doesn't spin in 2WD, but the spiders do. But with no load I suspect it's again pretty easy on oil.

Rear diff though has the usual abuse. But then again, mine is a whopping 5 quarts, and no limited slip, so perhaps not.

 

[kyoo]

5 qts in the rear diff??? both my rear diff and t-case take about a pint of fluid each... lol

 

[Donald]

Look on the Amsoil website for your exact vehicle, engine, transmission.

My Jeep takes ATF in the transfer case, but its a real transfer case for 4WD, not AWD and has a transfer case shift lever.

 

[Lyman]

My Jeep takes a special Mopar transfer case fluid every 30k miles.

 

[supton]

Originally Posted By: kyoo
5 qts in the rear diff??? both my rear diff and t-case take about a pint of fluid each... lol


Yeah, slight difference between a RAV and a Tundra.

2.2qt front diff, 1.2qt for transfer case. In a true Toyota oddity, the top-dog 5.7L takes from 3.7 to 4.0 qt in the rear diff (depending upon body and 2/4WD), while the 4.0L and 4.6L takes 4.3 to 4.9 qt. At least for 2010.

Weird, eh?

 

[SwampSurvivor]

My Jeep always spins the chain and front output as I don't have disconnecting hubs. It calls for ATF and that's what I run. I have been considering running something a bit heavier in it - maybe 5w30 engine oil since it does see hard use.

I wouldn't run gear oil in a NP231 case. There are no viscous couplings to get destroyed by using the wrong oil but it won't pump correctly, or at all, using gear oil.

Some transfer cases are a bit more picky. Especially those that have a "center diff" or some sort of viscous coupling.

 

[MolaKule]

Originally Posted By: kyoo
In GENERAL,

Are there any needs that a transfer case would have that a typical differential (let's say clutch type) would not have? I believe in general, the differential may want some limited slip additives that a transfer case would not necessarily need, but other than that?


Different applications require different fluids.

Different materials, different friction modification, etc., so there is hardly anything in common.

 

[UNC017]

The most critical question is whether or not hypoid gears are present. Most rear-drive differentials have a hypoid ring-and-pinion set and need GL5 gear lube, most transfer cases have chains and maybe a planetary differential with no hypoid gears and can use something like ATF or a manual-trans lube that would destroy hypoid gears in short order.

The next consideration would be whether clutch packs are present and what type of clutch packs. Some transfer cases have very specific (one might say 'exotic') fluid needs for the coupling clutches. Most limited slip clutches in a differential use a pretty basic LS friction modifier.

 

[LeakySeals]

You should NOT treat a TC like an engine, changing viscosity. Use whatever it states in the manual. I tried changing fluids because Dex III is getting hard to find. Bad move, the TC started shuddering and thumping rounding corners with maxlife. Had to go back to old Dex III and everything was fine again.