Nitro Gear 4.56 ReGear - Why the different Gear Oil???

[007Tacoma]

I have searched, and I have asked in another thread... I feel like this needs its own thread because I can't be the only one with this question...

Toyota Differentials (OEM) run LT 75W-85 GL-5 Gear Oil

Nitro Gears recommends using 80W-140 Gear Oil.​

So, I am curious...
:noidea:

Why the difference?

What is the risk of running the lighter oil with the Nitro Gears?

If you have regeared, what oil brand and weight are you using???

Background information: I have 165,000 miles on my original 3.73 gears with heavy loads and tons of towing. I had zero metal flakes on the drain at 75,000 miles and 150,000 miles. Last month, I upgraded to a Nitro Gears 4.56 gear set. I did the initial break in then drained and refilled with 80W-140 with the expected fine metal shavings a decent looking oil. I refilled it with Castrol 80W-140 per my mechanic's advice. Since then have put 2,500 miles on the vehicle, and I'm about to change the oil again just to ensure everything is okay. I have noticed that my fuel economy is way down. Power is up, but but I can't break 13MPG unloaded cruising at 55 MPH (I was as high as 18MPG fully loaded - not towing).

 

[rdruss]

I have searched, and I have asked in another thread... I feel like this needs its own thread because I can't be the only one with this question...



So, I am curious...
:noidea:

Why the difference?

What is the risk of running the lighter oil with the Nitro Gears?

If you have regeared, what oil brand and weight are you using???

Background information: I have 165,000 miles on my original 3.73 gears with heavy loads and tons of towing. I had zero metal flakes on the drain at 75,000 miles and 150,000 miles. Last month, I upgraded to a Nitro Gears 4.56 gear set. I did the initial break in then drained and refilled with 80W-140 with the expected fine metal shavings a decent looking oil. I refilled it with Castrol 80W-140 per my mechanic's advice. Since then have put 2,500 miles on the vehicle, and I'm about to change the oil again just to ensure everything is okay. I have noticed that my fuel economy is way down. Power is up, but but I can't break 13MPG unloaded cruising at 55 MPH (I was as high as 18MPG fully loaded - not towing).

They are speaking from their experience and also advising you that if you have a problem and don't follow their advice don't be surprised if warranty denied.

 

[Nobody Special]

4.56 put more power to the ground.
More power, more pressure etc...
A lighter oil won't protect as well, (but don't mention that to people who swear by 0W20, even though they are two different applications).

 

[007Tacoma]

They are speaking from their experience and also advising you that if you have a problem and don't follow their advice don't be surprised if warranty denied.

That doesn't explain the difference though...

My 3.73 gears looked great after years of heavy abuse with OEM gear oil (changed every 75K).

 

[007Tacoma]

4.56 put more power to the ground.
More power, more pressure etc...
A lighter oil won't protect as well, (but don't mention that to people who swear by 0W20, even though they are two different applications).

Technically, they are not putting more power to the ground. The ratio is different giving more turns of the pinion gear (input from the drivetrain) allowing the engine to spin at a higher rpm to exert the same amount of force. The pressure is actually lesser on the gears (all other things being equal), they are just having to turn faster.

 

[spartacus]

Technically, they are not putting more power to the ground. The ratio is different giving more turns of the pinion gear (input from the drivetrain) allowing the engine to spin at a higher rpm to exert the same amount of force. The pressure is actually lesser on the gears (all other things being equal), they are just having to turn faster.

You'are dead on. The one negative of regearing. Higher rpms equal less gas milage. What size tires are you running?

 

[007Tacoma]

You'are dead on. The one negative of regearing. Higher rpms equal less gas milage. What size tires are you running?

We are running 255/75R17 Kumho MT71s in C-Load.

 

[spartacus]

We are running 255/75R17 Kumho MT71s in C-Load.

You could go up a tire size and may experience some gain. As'far as why 85-140. ESGS recommends that too. There is a long explanation on their site.

 

[007Tacoma]

You could go up a tire size and may experience some gain. As'far as why 85-140. ESGS recommends that too. There is a long explanation on their site.

Thanks! I'll check it out! :thumb:

 

[007Tacoma]

ESGS recommends that too.

I'm guessing you meant ECGS.

 

[delloro]

...(but don't mention that to people who swear by 0W20, even though they are two different applications).

So why bring that up here?

Evangelize your motor oil viscosity religion elsewhere please. It is, after all, a different application.