SuaveGato

So I'm changing all of the fluids (Front & rear Diff's, Tranny & T-Case) in the recently acquired 4Runner: (1991 3.0L, 4x4, 5 speed). When I drained the T-case, it was clearly filled with some kind of gear oil and when draining the Rear Diff it appeared to be filled with ATF? Looked like ATF (red). Smelled like ATF, consistency of ATF? I thought Hmmmmm? And continued on.

Now, I'm reading the Haynes for refill types & Quantities and it calls for the following:

Manual Transmission oil: API GL-4 SAE 75W90 or 80W90
Differentials oil: API GL-4 SAE 80W90
Transfer case oil:So I'm wondering, did the idiot PO or a Jiffy Spooge type place accidentally fill my Rear Diff with the ATF and the T-case with the gear oil? WTF? Anyone ever hear of ATF in the rear end for any valid reason? This could explain the cause of my "mystery driveline clunk" too? Read 1/2 way down: http://www.ttora.com/forum/showthread.php?t=73792 Hope it didn't do too much or ANY damage? Who knows how long it's been in there?

Additionally, for purchasing convenience's sake I am going to run the 80W90 in all of the tranny & diff?s, sound ok? Also, am I reading it right and is the manual correct that the 3L 5 speed uses DEXTRON II ATF in the Transfer case, right?

And Finally, how do I know what tranny I have? Are there numbers on it somewhere that I can read to find which one I have? The Haynes manual lists the torque specs by tranny type (L43, W42, G52, R150 etc?) and I don?t know my ?type?? It?s the 3.0L, 4x4, 5 speed if that helps?

Thanks,
biGjOhn

runethechamp

No, the V6 MT transfer case is not supposed to have ATF. Best thing is 75-90 GL4.

You should have the R150 tranny with the V6.

thook

The only applications for ATF are hydraulics...other than someone adding it to the engine as a detergent, but that's not a factory recommendation or specification.

If someone did put ATF in the diff, that was a royal fork up. There are no pressure additives to adequately lub' the gears. It doesn't behave (stick to the gears) like a gear lube. The diff gears rely on the gear oil to be slung and adhere, not pumped as in the case with auto trannies and their mated transfer cases. I suppose I can only speak about Toyota assemblies, though, since I don't know much of anything about other manufacturers.

MudHippy

Oil can be a reddish color(or any color), but nothing smells like ATF. Except power steering fluid. NEVER TO GO IN AN AXLE. So flushing it all out would be a wise decision, to be safe.

The damage would be appearent on the drain plug as large bits/shavings of the gear metal.

SuaveGato

I thought that ATF in the rear end had to be a mistake as well? no Hypoid qualities there AT ALL! I hope it didn?t do any harm? I do have a weird metal on metal clunk occasionally though, hopefully if it's from the ATF in the rear end, this will fix it?

As for the Tranny, I checked my door sticker and found that I have the R150F tranny. According to the manual and another site I searched, the T-case on that one calls for Dextron II ATF in the CHAIN driven T-case? So what's the deal? Haynes says ATF, other site says ATF, y'all say gear oil? Decisions, decisions? I don't spose the gear oil could hurt?

If I had to guess though I'd say gear oil for the gear driven T-cases (needs sticky & hypoid qualities) and ATF for the chain driven T-cases, just as a lube, no pressure or heat created?

Anyone have the definitive answer?

Thanks,
biGjOhn

SuaveGato

I'm no Pro mechanic but it sured smelled like ATF to me and it was way more viscous than gear oil too. Me thinks it was ATF? The plug didn't look too bad, just some minor slivers and the some creamy silver paste... typical stuff you'd expect to find, so maybe, hopfully I got lucky? I'm sure it's real clean now! Any recomendations on what I should flush it with? Just some cheap motor oil maybe?

TC4RNR

i'm planning on changing all the drivetrain fluids to full synthetic oil on my 2nd gen, 4crawler has the best write-up, there is the link

http://www.4crawler.com/4x4/index.sh...ntheticGearOil


i decided to go with REDLINE full synthetic after the research, ordered 5 qts of MT-90 GL-4 for the 5spd trans and T-case, 5 qt's of 75-90W GL-5 for the front and rear diff's.

MudHippy

Yeah if you can afford it you can fill it TOTALLY full with something cheap of the same type, synth or not or both. Most stuff these days is compatible enough anyway, just not ATF and gear oil. Who knows what it might do?

Then jack up the rear axle and put it in gear. Let it sling the stuff around for awhile, then drain & refill.

Oh, the stock t-case that goes behind the R150F is the VF1A which takes gear oil. It's a chain drive, but so are the hydraulic-shift t-cases that use ATF, the VF2A and the A340H/F.

SuaveGato

Kewl, thanks. I think I'll just get some cheap WalMart 30 weight motor oil (or gear oil if it's cheaper?) and do what you suggested. I would think that the ATF would contaminate the gear oil in some way... break it down? The detergents can't be good either, you want the oil to stick to the metal NOT be striped off!
thanks.