I was surprised to see that T4R owners in Texas do use the 75-110 wt diff gear oil . they said they had no issues with using it.
you do see the shift issue when cold with 5wt higher that is hard to grasp...
you have an air conditioned garage !
Front & Rear Differential Oil
- Thread starter Dalko43
- Start date
I was surprised to see that T4R owners in Texas do use the 75-110 wt diff gear oil . they said they had no issues with using it.
you do see the shift issue when cold with 5wt higher that is hard to grasp...
you have an air conditioned garage !
Muzzle of Bees
New member
It does get below 45 degrees f here. If you have a manual transfer case and shift at the lower temps using a thicker oil it will be noticeable. Now those with the dial won't notice. Again I did not say it was harmful. I guess those that use deductive logic could not deduce that there is a difference for the short period the fluid is cold.
the transfer case fluids should be the exact toyota spec fluid. the diff oil being a synthetic fluid should not cause a harder shift when cold even it its 5WT higher.
unless you did the diff servicing it is possible in Texas they use a higher viscosity at the repair shops that your not aware of .
flyinhawaiian01
New member
Really? Show me your documentation on why Royal Purple oil is crap then.
flyinhawaiian01
New member
More than likely, you put an oil that contained friction modifier in it. Many oils, including my preference, Royal Purple, does NOT state that it has friction modifier mixed in, but it does. This will create friction in the synchronizers in the transmission and make it difficult to shift into gears. I know this from first-hand experience many years ago.
There's a reason why Royal Purple has a 75w90 oil and a "syncromax" oil, both are gear oils, but the straight numbered oil has friction modifier in it.
And a difference between 85 and 90 weight will not make any difference to the gears, bearings or seals, no matter what the temperature is. They will BOTH thin down at lower temps equally. Ie., at 0ºF, they will both be approximately 75W, and at 210ºF (specified in SAE J300 specs) they will be 85 and 90 weight. The shear rate for either of those oils are so minimal that, unless you're running the Baja 1000, a diff or transfer case will not have any difference in wear. Hell, even running the Baja, you probably won't be able to detect extra wear!
I use supertech 75w-90 because it's close enough and GL-5 is GL-5 and haters gonna hate.
I would bet a barrel of gear oil that most Toyota dealers use whatever 75w-90 or 80w-90 they can get in bulk for the cheapest. I would also bet that it is lower quality than supertech, and that doesn't matter either as long as it says GL-5 on it.
I would bet a barrel of gear oil that most Toyota dealers use whatever 75w-90 or 80w-90 they can get in bulk for the cheapest. I would also bet that it is lower quality than supertech, and that doesn't matter either as long as it says GL-5 on it.
Antman
Elite Member
Danimal
New member
Antman
Elite Member
Lester Lugnut
New member
Who told you that?
Woz1976-MT
New member
According to Royal Purple's website, RP Synchromax can be used in place of Toyota Genuine LF Type Gear Oil (fluid in the 5th gen transfer cases) -- it's noted in their "compatibility" PDF on the Synchromax product page. I'm have searched far and wide for a good synthetic that meets Toyota's specs, but this is as close as I've gotten to date.
I'm definitely no expert on the subject so use at your own risk (I think I'm going to try it... may call Royal Purple and ask them about it though).
you stated that you used 75-90wt in a manual 4X4 truck transmission you had and you did have a hard time shifting.
WHAT TRUCK WAS THIS ?
The few trucks manual trannys I worked did not use 80wt gear oil. used a special gear lube for the bushings and the shift effort to work properly.
down you area in Texas some use 75-140WT in the differentials
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aha2988
New member
How do you even shift bro?
x2 on 85w 140. but thats just what some off-road guys that build diffs all day recommend.
ADK Explorer
New member
So I'm looking to change my rear diff oil this weekend because before I did my breather mod I went through several washouts at least up to a foot deep, one was back in March when the water was full of ice chunks. I have just over 4000 miles but want to be sure.
My question is: where are you getting your oil and at what price? (75W90 sounds good enough)
I went to Advanced Auto saw Royal Purple for $20+ a quart and thought, "F no!" The guy said Amsoil and Redline are not worth the extra money (and he off roads). He said any decent mid price brand is fine. (especially if I will be changing mine frequently due to mucking through mud and water). Called NAPA and they only have Valvoline at $9.50 a quart. Wallyworld has SuperTech at $6 a quart but I don't know the brand and well, it's wallyworld and might be cheapo. I don't know?!
I'd rather not pay more than $8 a quart but you get what you pay for so all civilized input is appreciated. Thanks Brian
My question is: where are you getting your oil and at what price? (75W90 sounds good enough)
I went to Advanced Auto saw Royal Purple for $20+ a quart and thought, "F no!" The guy said Amsoil and Redline are not worth the extra money (and he off roads). He said any decent mid price brand is fine. (especially if I will be changing mine frequently due to mucking through mud and water). Called NAPA and they only have Valvoline at $9.50 a quart. Wallyworld has SuperTech at $6 a quart but I don't know the brand and well, it's wallyworld and might be cheapo. I don't know?!
I'd rather not pay more than $8 a quart but you get what you pay for so all civilized input is appreciated. Thanks Brian
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I have used mobil synthetic 75-90wt gear oil for a about 20 yrs. it now has the LS in it but no problems with any drivetrain gears . I replace it @40K miles . an auto store I use is CAP because I get a coupon and when I purchase 3 qts @$10 ea I only pay $20 for the 3 QTs.. I also buy the tranny fluid there. they now carry the WS toyota fluid .
CAP Consumer Auto Parts.
CAP Consumer Auto Parts.
NorthwoodsRunner
New member
Advance Auto had $40 off on $100 purchase and it was selling Mobil 75W-90 LS for $12.99 each so I bought 8 Qts of Mobil 75W-90 LS for $68 after $40 discount and taxes. So it is about $8.50 per qt including taxes. Royal Purple was too expensive and not sure if it is worth the money.
jthoms1
New member
A quick warning to all. I did my rear diff and transfer case last weekend and had intended to the front diff. However, I stripped the front diff drain plug. It takes a hex bit and as I learned if it's difficult to get out, it's easy to strip. Throw some PB Blaster on it before you try. I have a new plug on the way, but have yet to ass around with getting the old out.
NorthwoodsRunner
New member
Not sure what kind of tools you are using but I only use Snap On/Mac Tools 6 point sockets/wrenches/hex bits to prevent rounding. I had zero issue when I was doing the front differential with a Snap On 10mm hex. I stay away from 12 point sockets and poorly spec'ed tools.
75w90 GL5 is excellent in the diffs and transfer case. The 75W85 was developed to increase mileage, same for 75 LF. Toyota changed the AWD transfer case oil spec on my 200 Series Land Cruiser from 75W90 GL5 to 75 LF, nothing inside the case changed, most notably the Torsen T3 with its gears and clutch.
The front differential drain plug can be problematic to remove. The issue lies in the large 24mm thread size and smallish 10mm female hex required to remove it. The short of it is that it can round out, and frequently does. For those looking to get rid of the problem, Lexus installs a plug on some front diffs that has a male 14mm nut on it, so a regular 6 point socket or wrench can be utilized to remove it. The part number is 90341-24016. Toyota does not supply through their dealers.
The front differential drain plug can be problematic to remove. The issue lies in the large 24mm thread size and smallish 10mm female hex required to remove it. The short of it is that it can round out, and frequently does. For those looking to get rid of the problem, Lexus installs a plug on some front diffs that has a male 14mm nut on it, so a regular 6 point socket or wrench can be utilized to remove it. The part number is 90341-24016. Toyota does not supply through their dealers.
