Conventional vs Synthetic Gear Oil

Hey y'all,

My diffs are acting funny and I want to start my changing the oil in them. All I can find locally is synthetic for the

$29 75W-90 Synthetic Gear Lube - 1 Quart (Pack of 2)

75W-90. Is it advisable to use that or should I order conventional?

 

There’s a good discussion on it here:
https://www.tacomaworld.com/threads/synthetic-gear-mt-oil.512826/

 

Synthetic is fine. I'd suggest:




Mobil 1 is good, also

 

Yes, syn is better. If you have a mechanical slip diff, you don't need to add lsd additive. And go for the squishy bags - you will not need a funnel.

 

If you havnt done your diff oil in a long time, I suggest buying something cheap in the appropriate weight. Change it and run it for 5k miles. Think of it as flushing it out.

Drain it again and go with something like Amsoil or Mobil 1 and resume regular intervals.

 

Always remove fills plugs before drain plugs.
Its a bad day with a empty diff and no way to fill it.

 

Also this!

 

Any 75-90 gear oil should work fine. However ECGS recommends running Lucas 85W-140 Dino, according to their testing it is the best option.

https://eastcoastgearsupply.com/ft-2536-ecgs-gear-oil-recommendation.html

 

I did some reading on this the other night and changed my truck last night. I went with the Valvoline bags of synthetic 75/90 for the front diff and transfer case, Redline MTL for the transmission (manual) and conventional Valvoline 80/90 with CRC Trans-X limited slip additive.

 

OP has a 2000. It’s a 1st Gen.
He never said what components he is putting the gear oil in.
He also didn’t say if he has an Open Diff, or LSD.