Gear oil for trans and rearends

[Brock]

(12-09-2016 )Rawze Wrote:  

(12-08-2016 )Texasdude74 Wrote:  Transmissions and rear ends are about the only reliable things left on the newer trucks. The 50w synthetic changed every 250k seems to get most guys to 1.5-2M miles. I don't see anything to be gained by running old school, molasses looking mineral oil in there.

If you run with high torque,... 75-90 synthetic in tyranny for better life. Highway and dry-van reefer, 80k or less, .. 50w is fine. easier to shift.

rear ends,.. 75-90 or 85-140. It helps keep the backlash down in the bearings and increases tire edge wear life. As well, longer gear train life, and less chance of wheel seals bleeding when it gets warm.

Odd. I was told by Eaton that under no circumstances could you use a 75/90 gear lube or anything of that nature. They say there are galleries that are not wide enough to support the thicker oil and you will run components dry causing premature wear.

I wanted to know because I was considering doing it.