gear oil opinions (1 Viewer)

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portland oregon
I've got about 1500 miles on my brand new H55 now - and want to drain the fluid and refill, and while I'm at it install the new hex head plugs from valley hybrids
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First thought seeking opinions: i'm going to try royal purple synthetic gear oil - per recommendation from fellow mudder. my H55 is pretty clunky moving into 1st and 2nd - more so in the morning when it's cold. mellows out once it's warm.

Second thought: I'm feeling a bit of sticker shock at the cost of gear oil these days (the H55 need 5.1 qts) cost to drain and fill is approaching $100.00.

Third: Since i know I'm doing a front knuckle job in the next week or so...i'm feeling like collecting the 2 month old gear oil out of the transmission and running it through several sieves and let it drain across a strong magnet - with the intent of reusing it for the front diff.

3 more quarts of gear oil for the front diff = another $50.00

the cost of motor oil and gear oil at auto parts store full retail makes a case that it's barely worth it to change your own fluid.

thoughts?
 
My opinion is that Syn oil is great...BUT...totally not necessary in LandCruiser diffs, t-cases and/or manual trannys. There's nothing wrong with it but for that application you gain absolutely zero benefits. And as you've noted, the price difference is large.

I recommend straight 80-90 or 75-140 and you will be good.
 
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I am not sure about H55 but in H42 in my FJ40 I use GL-4 rated gear oil It is recommended because gl-5 gear oil can have additives that can corrode soft brass parts in H42 I use brad penn at approx $10 a quart a little over 4 quarts but 40 bucks instead of 100. Transmission shifts more smoothly with GL-4 also
 
All I’ve ever used over 40 years of cruisers ownership is straight 80-90 with zero issues. These trucks are made to run on it. And I also use rotella in the engine with great results, these are old school tanks built for 3rd world use
 
IIRC factory spec for the H55F is GL-4, which is a little harder to find.

The 5 speed in my BJ74 is the only place I use a synthetic fluid (ok, it's in the auto in my HDJ81 as well..). I switched years ago from good ol' 80-90 to Redline MT-90 and there was a noticeable improvement in shifting, both in my current BJ74 and my previous BJ70 (both H55Fs). I've stuck with it ever since.

YMMV, but mine didn't.
 
Buy 80-90 in bulk (5 gallon bucket) at Napa.
I wonder if some folks who get a brand new H55 and put super duper synthetic in it right from the get go are the ones that end up complaining about notchy shifting? Maybe it takes 50k miles to wear in and get super smooth, maybe even longer with super slick synthetic?
 
X2 on Redline MTL. Going from stock to Mobil 1 improved shifting in my Taco some. Going to MTL vastly improved shifting. And it is GL4 so doesn't eat the brass/bronze.

I can't speak to longevity over reqular oil but I like the shifting improvement. Gear oil is expensive but so is a breakdown/rebuild.
 
Buy 80-90 in bulk (5 gallon bucket) at Napa.
I wonder if some folks who get a brand new H55 and put super duper synthetic in it right from the get go are the ones that end up complaining about notchy shifting? Maybe it takes 50k miles to wear in and get super smooth, maybe even longer with super slick synthetic?

i filled mine the first time with sta-lube GL5 - that's what is in it right now - and it shifts pretty notchy...maybe it's the gear oil? or something else?

I mentioned it to a fellow portland mudder who also just did his H55 swap - and he suggested the royal purple. i'm open to experimenting...but dang that stuff is $$$. sta-lube is only $30 bucks - not too painful.
 
It is indeed MT-90. Don't know why I call it MTL.
IMG_20180716_185134154_LL.jpg

One more data point. My FJ Cruiser was a whore to shift until I went to this.
 
I’ve got 2 gallons of the straight 50w Mobil 1 synthetic lube that i bought early on to help fix a transmission knock. @OSS correctly troubleshot it over the phone and it was a misfire.

I’m getting a new split case and h55 in the coming weeks and I’m debating on using that $100 fluid I’ve got.

I was thinking that or amsoil for all those new parts. I’ll keep doing research.

@RAGINGMATT how much per can of those beauties?
 
Update to my previous post:
The Mobil1 75W-90 bottle USED to say that it was suitable for manual transmissions... but it doesn't say that any more.. and Mobil does not recommend it for transmissions any more.... and if you use the new stuff you will soon find out why... shifting aint so great.

Another rep from Mobil contacted me when I questioned the "no suitable oil" response, as I was initially interested in Mobil Delvac Synthetic Transmission Fluid 50 to use in the H55F transmission and transfer case. Mobil Delvac 50 is a synthetic monograde GL-4 which "has the same viscosity as most SAE 90 gear lubricants at the high end of the temperature-viscosity scale." It is designed for manual transmissions (and transfer cases) only and is safe for copper/brass alloy synchros. It should NOT be used in the differentials since it is GL-4, not GL-5.

The official statement from Mobil in regards to the suitability of Mobil Delvac 50 to be used in a Land Cruiser transmission (and transfer case) while meeting Toyota's GL-4/GL-5 SAE 90 wt, specs:

"Mobil Delvac 50 is a good choice for your application. The Mobil Delvac 50 is a monograde fluid and meets the viscosity requirements of a SAE 90wt gear oil."

I also contacted Redline. Their recommendation (along with others on this board with MT Land Cruisers) is Redline MT-90 75W90 GL-4 Gear Oil.

... now I've gotta choose one...
 
I’ve got 2 gallons of the straight 50w Mobil 1 synthetic lube that i bought early on to help fix a transmission knock. @OSS correctly troubleshot it over the phone and it was a misfire.

I’m getting a new split case and h55 in the coming weeks and I’m debating on using that $100 fluid I’ve got.

I was thinking that or amsoil for all those new parts. I’ll keep doing research.

@RAGINGMATT how much per can of those beauties?

how much per can of those beauties? <-- yikes - $33 per liter(quart / liter about the same - so you need 6 of these)
upload_2018-7-16_16-44-19.png

yikes...i'll pass!
 
I’ve got $120 in the mobil stuff. I’ll likely just use that to get it out of the shed.

I’d pay it if it means it’s the best I can get for the new tcase and trans.

@orangefj45 said just normal gear fluid is all he suggests.
 
i filled mine the first time with sta-lube GL5 - that's what is in it right now - and it shifts pretty notchy...maybe it's the gear oil? or something else?

I mentioned it to a fellow portland mudder who also just did his H55 swap - and he suggested the royal purple. i'm open to experimenting...but dang that stuff is $$$. sta-lube is only $30 bucks - not too painful.
I would put in the correct GL4 before drawing any conclusions about shifting, as I understand some GL5 oils are more slippery due to differences in additives and this will lessen the "grab" of the synchro making shifting harder. Ditto for generic synthetic gear oils. I would run the regular Dino 80-90 GL4 for a good while at least till I felt things were broken in and shifting smooth. Then if you still feel the need to try the Redline go for it.
 
Buy 80-90 in bulk (5 gallon bucket) at Napa.
I wonder if some folks who get a brand new H55 and put super duper synthetic in it right from the get go are the ones that end up complaining about notchy shifting? Maybe it takes 50k miles to wear in and get super smooth, maybe even longer with super slick synthetic?

I have used the 80-90 in bulk from Napa as well, and bought the handy pump that fits the 5 gallon top. Really easy to change ou the fluid. I have about 2000 miles on my new H55 and it isn’t clunky or notchy, what fluid did you use for break in?

[QUOTE="Paul DiNapoli, post: 11782771, member: 128043"

Third: Since i know I'm doing a front knuckle job in the next week or so...i'm feeling like collecting the 2 month old gear oil out of the transmission and running it through several sieves and let it drain across a strong magnet - with the intent of reusing it for the front diff[/QUOTE]


Wait, are you serious about reusing your gear oil? The gear oil used for breaking in your new H55, you are kidding, right?
 
Wait, are you serious about reusing your gear oil? The gear oil used for breaking in your new H55, you are kidding, right?

well that's what i did ask... will it actually be full of metal - or are we all being superstitious? i'm asking for real feedback...are we all dumping a gallon of new gear oil for good reason - or just because someone said so 50 years ago and no one has ever questioned it.

i wouldn't use it if there was obvious metal shavings - but my question is - how bad is it really? at what mileage do you drain the oil out of any transmission? 100 miles? 500 miles? if it's full of metal worthy of replacing at 500 - what about between 250 and 500? or that last 100 from 400 to 500? or 800 to 1000?

i guess i did ask for opinions - so @evilorgoodtwin - thanks for the feedback..if i'm crazy - call me crazy and i'll just spend the $$$ on new gear oil. i'm just wondering if we're taking action based on facts.
 

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