New Truck - Want to change Manual Transmission Oil, Diff, transfer case

Hello,

I just bought a 1997 Toyota Tacoma, 2.7L, 4x4 (no locker), manual trans to be using around town. I want to keep this truck running well. It has 244k.

I just want to verify that I have the correct fluid and have done a lot of searching and I have read the manual.

So basically, to keep things simple I can run Valvoline SynPower Full Synthetic SAE 75-90 gear oil in the manual trans and transfer case? (I know you all recommend Redline, but I don't have access to it and the Tacoma isn't my daily driver).

For the front and read diffs the manual says to use, "Hypoid gear oil API GL-5". What is a hypoid gear oil? Valvoline SynPower Full Synthetic SAE 75-90 gear oil said it can be used as a hypoid gear oil on the back.

So... I just run Valvoline across the manual trans, diffs, and transfer case?

Is that correct?

 

Honestly, brand doesn't really matter that much. Just make sure the weights are as recommended by the manual.

 

The transmission takes GL4 rated 75w90 gear oil, make sure it's not GL5 specific (not good for synchronized manual transmissions)

The diffs use GL5 as you mentioned the manual states

 

• Formulated to maintain excellent low-temperature fluid protection
• Helps provide outstanding thermal stability for cleanliness and longer service life
• Contains special additives to assist in protecting gear teeth from rust and corrosion and reduce chattering in limited-slip differentials
• Recommended for conventional and limited-slip differentials and non-synchronized manual transmissions where API GL-5 or API GL-4 fluid is specified
  

Yeah, I heard not to use GL-5 specific fluid in the manual trans. Above is what Valvoline says in the back of the bottle. So, I guess Valvoline across the board?

 

*edited - that stuff says it's for non-synchronized transmissions so you need GL4 specific gear oil*

For what it's worth, I have heard that it's not ideal to use synthetic gear oil in the differentials...places like East Coast Gear Supply recommend using regular Dino oil in the diffs (supposed to handle high heat better). But if your truck is mostly just being used as a commuter on the street then I doubt it'll ever see high temps that would cause issues. More of a concern for people that doing heavy offroading or towing.

 

Always remove the fill plugs before removing drain plugs. Replace the plug washers with new ones and they are not all alike. Amazon 12 pc. Transmission, differentials and transfer case plug washers $13.

 

from a knowledge base ...

A hypoid gear oil is a lubricant that is designed to operate effectively with hypoid gear designs. Most gearboxes and differentials use hypoid gear designs and the lubricant must contain EP (extreme pressure) additives to prevent wear between the sliding surfaces of a hypoid gear mesh.

In English, all this means is that the pinion gear does not mesh with the ring gear at the 3 o'clock center-line position. It meshes at a point above/below the center-line of the ring gear.

 

I just changed mine yesterday using same valvoline products.

 

Your trans is synchronized.

It has bronze syncros.

Therefore, GL4 is what you want to use.

Its harder to find, but you don't have to use boutique stuff like Redline to get it

 

Good catch I didn't even see that in the description