what transmission and transfer case oil to use?

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rideglobally

rideglobally

Nullacruiser
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probably covered many times. i have a 1983 hj 47 with H 55 transmission. what oil to use to change transmission, transfer case and differentials? should i use synthetic oil? the transmission and and transfer case been there a while. the differentials are newly re geared about 4000 miles. thx
 
Valvoline 75W-90
 
You'll get lots of opinions but there real answer is: it almost doesn't matter. Any gear oil will work. Toyota recommends GL5 80w-90, use that.

There will be some who say that GL5 80W-90 will "eat" yellow metals like brass syncros. But all modern gear oils are buffered to prevent this. So you can use the cheapest of parts store generic 80W-90 and it will work fine for decades.

You can get a step more sophisticated and run an MT-1 rated oil in the transmission if you're worried. Redline MT-90 is this and works great in Toyota gear boxes. Expensive though. Recently at AutoZone, I noticed that the Chevron Synthetic 75W-90 is MT-1 rated, so I've been trialing that. And it's a bargain and less than Valvoline 80W-90 conventional oil. So far in my H55 the shifting is great and I expect no problems at all. I'd also recommend the same gear oil in tranny and t-case since often they cross pollinate and leak from one to the other.

In the differentials, any conventional GL5 80W-90 will serve. The cheaper stuff may in the end be better, because you be more willing to dump and change cheap oil that gets water in it. Expensive synthetic gear oil is really hard to change out after a trip with water crossings, but you really should.

Bottom line: Fresh clean gear oil is good. Water or dirt contaminated gear oil is bad. Old gear oil should be changed.
 
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Cruiserdrew said:
You'll get lots of opinions but there real answer is: it almost doesn't matter. Any gear oil will work. Toyota recommends GL5 80w-90, use that.

There will be some who say that GL5 80W-90 will "eat" yellow metals like brass syncros. But all modern gear oils are buffered to prevent this. So you can use the cheapest of parts store generic 80W-90 and it will work fine for decades.

You can get a step more sophisticated and run an MT-1 rated oil in the transmission if you're worried. Redline MT-90 is this and works great in Toyota gear boxes. Expensive though. Recently at AutoZone, I noticed that the Chevron Synthetic 75W-90 is MT-1 rated, so I've been trialing that. And it's a bargain and less than Valvoline 80W-90 conventional oil. So far in my H55 the shifting is great and I expect no problems at all. I'd also recommend the same gear oil in tranny and t-case since often they cross pollinate and leak from one to the other.

In the differentials, any conventional 80W-90 will serve. The cheaper stuff may in the end be better, because you be more willing to dump and change cheap oil that gets water in it. Expensive synthetic gear oil is really hard to change out after a trip with water crossings, but you really should.

Bottom line: Fresh clean gear oil is good. Water or dirt contaminated gear oil is bad. Old gear oil should be changed.
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thx, very helpful
 
I installed a H55 and spit case into my '70 FJ40 last year. Before I purchased the gear grease I asked the same question in my club house and was told not to use GL5 for the reasons stated above, to slick and would damage some of the bronze synchronizers. I was told the Redline MT-90 GL4 was the best to use so I put 5 quarts in the H55 and 1 1/2 quarts into the split case. The problem, when I shift I get a clattering of teeth unless I move the gear stick slowly. Could it be the GL4 is to slick and isn't allowing the synchronizers to work properly? Might it be a good idea to go back to a conventional gear grease like the Valvoline?
 
FWIW - Disclaimer: "I'm not advocating this product, but just listing what I used."

As mentioned above, I used Brad Penn when I changed Transmission & Transfer case fluids last year. It was cheaper than the Valvoline 80W90 that I could get at Wally World or Amazon, and a Big Brown truck brought it too my door, free of charge...

This is the stuff I used:
IMG_3484.webp

IMG_3480.webp



Note: As mentioned in post #4, as well as by a very reputable LC mechanic on this board, most any Dino GL4 or GL5 will suffice.

For the Differentials - I used GL5 per Toyota's specs, my product of choice was Valvoline 80W90.
 
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My H55F and my R151F hate 80w-90 of any flavor (I've tried several). Especially when the temperature drops into the teens. The only oil that works for me is the non-syn 75W-90 Valvoline. It was recommended to me by a Toyota engineer buddy.
 
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FWIW, found this from google search. I had recently changed tranny and xfer oil with Valvoline HP 80w-90 that got a 1B rating.

Screen Shot 2017-04-17 at 9.36.16 AM.webp
 
thx all, wow not that easy after all. my h55 has a small grind when down shifting from 5th to 4th, going to Alaska for the summer leaving May 1. maybe that helps. by the way how many quarts of oil for the transmission and transfer case? thx
 
lenmn said:
FWIW, found this from google search. I had recently changed tranny and xfer oil with Valvoline HP 80w-90 that got a 1B rating.

View attachment 1442563
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Reviving this old thread with a question about Valvoline High Perf 80w-90. The ASTM testing suggests it should be safe in synchro transmissions, yes? Does anyone know why the bottle specifies "Designed for use in non synchronized transmissions where GL-5 is specified"?

Thanks! Planning to do a full fluid swap soon and was leaning toward the Valvoline High Perf 80w-90 for diffs, tranny, t-case.
 
this is what I found online to meet the spec. with out breaking the bank.' Ultra plus SAE 75W-90 Synthetic Gear Oil APL GL-4 " 5 gallon shipped to my door.
 
bdsmitty88 said:
Reviving this old thread with a question about Valvoline High Perf 80w-90. The ASTM testing suggests it should be safe in synchro transmissions, yes? Does anyone know why the bottle specifies "Designed for use in non synchronized transmissions where GL-5 is specified"?

Thanks! Planning to do a full fluid swap soon and was leaning toward the Valvoline High Perf 80w-90 for diffs, tranny, t-case.
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How cold do you get? I found that 80W90, and syn, doesn't shift well, especially 2nd gear, when the temperature drops. I was told by a Toyota guy to run the 75W90 conventional for that reason.
 
pappy said:
How cold do you get? I found that 80W90, and syn, doesn't shift well, especially 2nd gear, when the temperature drops. I was told by a Toyota guy to run the 75W90 conventional for that reason.
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Not very. I live in Charleston, SC so the truck will rarely see any cold weather use.
 
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