Transfer Case Oil Change

Hi all, this is probably beat up subject but seems no definitive answer i was able to find so hoping to get answer, i am planning to do my 15k change diff/rear/front/transfer and seems some people do it with

$30 75w-90 Synthetic Gear Lube - 1 Quart (Pack of 2)

75w-90 cross board and no issues some do it with ams oil (which is what my last service did) however some do the 75W, I checked with my local dealer and they basicly were 0 helpful and said it be 3-4 weeks before i get it.

I plan to use valvoline 75w-90 gear oil, was wondering if anyone used it and how it was, and can i use it same for transfer case?

if not whats so special about it ?

Thanks in advance.


appologize in advance if this has been covered 100000000 over already if u can kindly share any links would be helpful, i found few threds but didnt get definitive answer


thanks.

 

I used Redline MT-LV. Why are you changing the fluids at 15,000 mile intervals?

 

There is virtually no difference between factory spec and

$30 75W-90 Synthetic Gear Lube - 1 Quart (Pack of 2)

75W-90, except for price. Why are you changing diff and transfer case oil so soon?

 

$30 75W-90 Synthetic Gear Lube - 1 Quart (Pack of 2)

75W-90 is perfectly fine. It’s a transfer case, it doesn’t really care what’s in it.

Source: 45K miles on conventional 80W-90 GL4 in my transfer case. Shifts better than it did on the thin stuff with much less frequent clunks when shifting into 4Hi at speed.

 

I did oem fluid at 18k. Truck was around 6 years old at the time.

You can get by with one can of oem fluid for the transfer case. I bought 2, but hardly used any from the second can.

Fluid was still very clean and it would have been just fine to top off with a little of the old fluid.

The front diff was noticeably dirty. The rear diff and transfer case could have gone a while longer.

 

I went through the same quandary the OP did with my vehicle and went with the respective Redline products for everything. Next time I will keep with the 70W or 75W for the transfer case and go back to 90W dino oil for the Diffs. From what I can tell there is nothing special about the Tacoma Diffs. The reason, I believe, Toyota calls out the low viscosity oils is for the gas milage requirements with the Feds. Since our trucks have no way to boast about their gas milage I don't see the point in continuing with the synthetic/low viscosity stuff. When I get my diff gearing done I may go with the 140W stuff.

The only thing about the Transfer Case is it does have an oil pump within it that may be finicky about the viscosity of the oil. And as has been addressed it is only one liter. Use a quart and put back a bit of the old oil to top off.

 

The thin stuff is for fuel economy. I too run Dino oil and I go with 85W-140. That is for a number of reasons, I drive hard/fast, high temp environments, low gears, and the gear manufacturers suggest it.

Transfer case does have a pump, but it’s not picky. I’ve driven 90 oil in 0°F temps. It’s fine. Have to remember that the VF2BM in the 2nd gen is very similar to our transfer case and called for

$30 75W-90 Synthetic Gear Lube - 1 Quart (Pack of 2)

75W-90 GL4/5.

I have seen one guy say his transfer case didn’t shift right running 75W-90 in extreme cold, but there is no proof that the problem was the transfer case and not the ADD. The transfer case usually shifts immediately, despite temps (in my experience anyways). For me in cold weather the ADD took a bit to engage, especially at cold temps with 85W-140 and at low speeds. It did go though after about 20 seconds.

 

My truck is dedicated to overland, so on highway to get to destination then rest is offroad. so do drive alot in 4h or 4L.

anyone experience with valvoline oil? should do

$30 75w-90 Synthetic Gear Lube - 1 Quart (Pack of 2)

75w-90 or go higher 75-140? i am also regeared.

 

I’d stick to 90. The transfer case sees very little load on any of the parts besides the chain in 4wd and the planetary in low. Gearing will spin things in the case faster but it doesn’t cause more load or wear. I do think 140 in the diffs is a good idea with regears.

 

any take if valvoline is good or there others, i see bunch of people saying nothing beats amsoil, but its hard to find in any stores, seems like u have to direct order. seen few videos people using Valvoline if anyone has any feedback on that.

 

Valvoline is fine.

 

If this was a 2nd gen that would be a no no since its specifies a GL-5 oil. But the 3rd gen like yours specifies a toyota special 75W GL-??? . I checked on the amsoil online catalog and for my 2nd gen there are a couple of weights of Gl-5 (i use 75W90) but there are no references at all to the what they recommend for TC oil in the 3rd gen

 

Realized I actually use MT-LV in my transfer case.

 

I dont have a 3rg gen owners manual. What does it specify for gear lube? Does it even mention a GL spec or just give a Toyota part # for their magic 75W?

 

In High School I had a buddy with a really nice Toyota Pickup. This was around 88 to 91. He had bought it in Florida and it was all set up for the beach and sand. Sweet rig. But up in East Texas he didn't need to drive off road as much (at all) so he went a year w/o changing the fluids in the t-case. When we finally took it up to a deer lease, he didn't need 4wd but thought it would be good to put it through its paces. The T-Case started throwing over heating alerts. When we took it back to town and he got it serviced they said it was a little low and the lubricant had set up and got too thick to circulate.

They took the T-Case a part (no forbidden glitter) cleaned out the goo, and put in some new fluids. Told him to run that truck off road once a month for at least 10 minutes in 4H.

So here we are, some 35 years later. Better fluids and lubricants with better additives. Better transfer cases with better seals. Not anywhere near the beach and salt water. And I STILL make it a point to get out and ensure that I spin that T-Case for at least 10 minutes every month. Probably better for my soul and mental health to have an excuse than it is for the fluids but it keeps my bubble on level.

 

Now I dont know the differnce btween the 88 TC and my 2015 TC (except one is manually shifted and mine is electronic) but the section (primary shaft) that is engaged in 2H is always spinning in the TC. Its only the shaft that is connected during 4H (or low) that starts spinning (connected by chain to the main shaft). So the lube is always being stirred up even in 2H

The only reason to use 4H once in a while on mine is to engage the actuators (TC and front diff), spin the front driveshaft and possible stir up lube in front diff.

So just trying to understand the need to us 4H in a manually shifted TC to keep oil from setting up??

 

Changed the order of the quotes hoping one answers the other.
I'm not entirely sure it does keep it from setting up.

What I am entirely sure of is that my OCD and urge to get off the pavement have psychologically fooled me into thinking that advice from Cooter's Garage in Hillbilly-Ville East Texas from 3 plus decades ago still applies and should be followed as 4wd Cannon / Dogma. Does that explain it better?

 

I've been using the below GL-4 in my vehicle's manual boxes, transfer cases, and transaxles for decades.

https://www.amsoil.com/p/amsoil-75w-90-manual-transmission-transaxle-gear-lube-mtg/

Cheers

 

The only real issue is if you use a GL-5 in a manual transmission that specifies GL-4.

GL-4 is adequate for other applications like TC's and diffs., just doesn't have the level of EP additives that GL-5 does.

The main difference between GL-4 and GL-5 gear oils is the amount of EP additives. Sulphur/Phosphorus containing products are used as EP-additive. This additive has the purpose to prevent the occurrence of micro-welds on the gear flanks at the local high temperatures which prevail in EP circumstances (temperatures well in excess of 800℃!) GL-5 has roughly twice the amount of EP additives compared to GL-4, which is why it is often used in high-pressure circumstances such as in a front axle and rear axle differential.

Sulphur/Phosphorus additives however have an unfavourable property: they can react aggressively towards bronze and copper. This can be disastrous for the synchromesh rings of a gearbox. Therefore it is not recommended to use GL-5 in a gearbox unless the manufacturer allows this.

 

If you're worried about cold weather performance and/or want a compromise between 75w-lv and

$30 75w-90 Synthetic Gear Lube - 1 Quart (Pack of 2)

75w-90, Syncromesh fluid is a good alternative. Fairly available anywhere you go and closer in viscosity to 75w-lv than 75w-90 is.

I switched to syncromesh after running redline 75w-lv due to not wanting to pay 50$ for that litre again. I see temps down to -43* and I haven't observed a difference in performance