What types of fluids do you use in your truck? Why?

This question includes brands, weights, viscosity, etc.

 

Use whatever is recommended per owner’s manual and within your mean/budget.

Just because 4 people tells you they use mt90 don’t mean royal purple or castro 75w90 is not compatible. Or switch to full synthetic when non synthetic is fine.

This topic is similar to suspension gurus comparing Fox to Kings or ADS. It’s preference.

 

Erl and lots of it.

 

Whatever we have in stock at work

 

Use Toyota for radiator and transmission fluids and not picky on brand for gear boxes, engine, steering fluid, and brake fluids but use designated weights and types per FSM. For LSDs Supertec has worked with the included additives. Often run Supertech gear oil, motor oil, and brake fluid but sometimes find some semi or full synthetic motor oil on sale like from Chevron, Mobile, or Valvoline. Sometimes can get gallons for gear boxes and other times 1 quart bottles depending on specs (e.g. 80-90 vs 75-90). Best price could find for power steering fluid flush was Valvoline Dex/Merc Automatic Transmission Fluid (ATF) 1 GA.

Seems like this thread pops up and gets debated over and over.