Which type of gear oil is best???

[mcfj40]

Does anyone know what type of gear oil is best to use for the 3spd tranny and transfer case? Also, I need to know how much to put in each one. My mechanic filled it with Lucas oil and it doesn't seem to be doing the trick.

Thanks

 

[CruisinGA]

That lucas stuff is the shiznit, I used it in my engine, made a very noticable difference. Switched to 20w 50 syrup so I don't need it in the engine anymore.
I would not fill the tranny and transfer 100% with it, a 50-50 or 25-50 mixture lucas to standard dino oil would be fine. I changed the oil in the F&R diffs, transfer and tranny in one day last week, used the cheapest stuff I could find cause I'll be in every one of those components for rebuilding in the next month. $23 for a 5 gallon bucket of Coastal 80/90 (autozone) , $50 for a very good industrial 5 gallon bucket oil pump.(Napa) Makes changing gear oil a snap. Standard 80/90 is all you need, you can get fancy if you want, but I change my oil so much I can't warrant spending a lot of money on anything special.
BTW-Just fill the tranny transfer and diffs till oil comes out the fill hole. But since you asked here are the capacities according to Mr Haynes: 2 pints to a quart I think.
3spd tranny 3.6 US PT
3spd transfer 3.6 US PT
There ya go. Post long enough for ya? :-*

 

[axlechassis]

to answer your question the best gear lube available is the amsoil gear lube. You can find cheaper synthetics but none better. If your running gear is in good order filler up and fogetaboutit. You will hear lots of opinions on this. I have been studying this for the past 25 years and the amsoil still comes out top of the gear lubes.

 

[woody]

If yer the type that changes your gear lube per mileage (ie: every 50k) then the expense of Amsoil or something else is worth the peace of mine.

I change mine every few trips, so cheap is better. Engine oil gets changed at 40 hours (yes, no odomoter, just an hour meter), usually the diffs and trans/t-case at the same time, if not every other time. $25 for 5 gallons goes a long way.

For a daily-driver rig, the synths are nice. For a trail-only rig, not worth the $$, IMO.

 

[Guest]

Buy Gear Oil in bulk that can be used in all of your Cars or at least most.
I currently have Valvoline HP 85W/140 in Diffs, Transfercase and Gearbox. Will next time change over to Limited Slip SAE90, Bcouse it is able to be used in my and Dads Cars.

 

[SpaceGhost]

I am a believer in the Amsoil line of products. Run it in everything I own. Become a dealer and buy at discounts. It made my SM420 shift like a champ.

I also find that when mixed with water in the diffs, the internals don't rust up, and the water seperates better than dino oils.

Run the good synthetics in your saginaw pump and your steering will stay cooler. Stuff pours easier and has a much higher temp breakdown point. Yes I am a dealer.

 

[woody]

now here's an opinion question...I run a 72 t-case, and she's a whiney bugger. And yes, just rebuilt too, but those straight-cut gears aren't quiet.

Does Amsoil lube, or a Lucas additive, or 80w140, or anything else help quiet these down?

 

[IDave]

ditto Woody's query.

 

[Cruiserdrew]

Question for Space Ghost-What specific synthetic do you run in your Saginaw pump? Mine does not have a cooler though I have one waiting to install. Also interested if you use power steering fluid or ATF.

 

[woody]

I run Valvoline PS semi-synth in my steering system, no complaints. Only a $1 more per quart too, and readily available. Have an inline cooler (need a bigger one I think) and installing hydro assist soon (I hope!)

 

[axlechassis]

now here's an opinion question...I run a 72 t-case, and she's a whiney bugger.  And yes, just rebuilt too, but those straight-cut gears aren't quiet.

Does Amsoil lube, or a Lucas additive, or 80w140, or anything else help quiet these down?

I doubt the amsoil would help quiet gear noise. It did'nt on my 63 land rover which had a noisy bunch of gears. Personally I would put some in because it wont hurt anything and there is a certain peace of mind knowing that you've got tip top oil in there while you listen to the gears whine.

 

[CruisinGA]

Woody-Supposedly that magical Lucas stuff is supposed to supress gear whine. I would try either 100% Lucas or a 50-50 mixture and see what that does. My transfer is not that loud, and its the same as yours. And its not rebuilt. ???

 

[CruisinGA]

I run Valvoline PS semi-synth in my steering system, no complaints.  Only a $1 more per quart too, and readily available.  Have an inline cooler (need a bigger one I think) and installing hydro assist soon (I hope!)

Does hydro assist use the PS pump for pressure? I'm assuming it works like hydro assist on a tractor, where you have manual linkage but when you turn the wheel the hydraulic ram provides assistance? Sorry for the digression.

 

[woody]

Does hydro assist use the PS pump for pressure? I'm assuming it works like hydro assist on a tractor, where you have manual linkage but when you turn the wheel the hydraulic ram provides assistance? Sorry for the digression.

http://www.westtexasoffroad.com

Matt modified my PS box for porting, the pump is tweaked per his instructions, an inline cooler is in place, just need to order up a ram...once my histeer is done, this mod is next. Solid links are all kept in place, ram provides assistance when the spool valve bypasses pressure due to resistance in the steering, ie: against a rock. Ram is relatively "passive" during normal driving.

 

[woody]

spaceghost says - "for the hydro assist with a howe pump and reservoir, it's hydro fluid from Amsoil" and "for the saginaw I ran synthetic, amsoil atf"

He's got the Howe pump now....used to run a "stock" GM saginaw pump.

"word from the massa"....lol

 

[pablo]

Everyone,
I just cracked open my new SM420 the other day and I lucked out and have yet found a reason to rebuild. However, the sluge and a small bit of rust (probably from the power wash at the junk yard) does cause me to consider something to clean that out. I once read in JP Magazine a oil that they recomended for the lazy and poor who use junk yard parts in their as is condition. Anyone know of such lube? I once used synthetic lube in my trash J30 and it made it hard to shift when it was like 20 degrees outside. But that was when I replaced lube that was the same color as the skin of a salmon at the supermarket. That transmission is trashed now and barely shifts.
Pablo

 

[IDave]

I will say I added Lucusoil to my tranny and transfer and the whine stayed the same, or perhaps even increased!

I'll be taking it out.

A mechanic friend has suggested 80/90 LSD oil mixed with Moly Oil. That's my next project.

 

[1980FJ40]

I had an old Kaiser M715 with the np200 t-case. Man that case would run hot and even boil the regular 90w oil. I put some Amsoil in and it ran alot cooler. It didn't do anything for the noise though! I would run this stuff again with no questions asked!

 

[Overlord]

The FJ60 manual calls for 90w in the tranny and t'case. I'm wanting to go with AMSoil, but AFAIK they don't make a 90w. So, would running 80w-90w be ok?

Sean

 

[Guest]

The Manuel says to use SAE 90 not 90W.
If you have a LSD in the rear, You may as well use LS90 in the Gearbox and Transfercase aswell.

If Amsoil is so good why don't they have a proper Dealer Network in Australia?
Best Oil you can Buy is Penrite(Nothing comes close, Is also Owned and Made in Australia). I use Valvoline.