Changing diff fluid

[bigBP]

Planning on changing my differential fluid this weekend, I recently put in a detroit truetrac. Right now I've got 80W-90 in it, but I've read were people recommend putting in 75W-90. What are the benefits of putting in the 75 verses the 80?

[hcvone]

Most manufacturers are selling 75-90, I used to see a lot more 80-90 some years ago. I have used 75-90 Amsoil and Red Line in the past. You will be fine using what you have.

[snoman]

Planning on changing my differential fluid this weekend, I recently put in a detroit truetrac. Right now I've got 80W-90 in it, but I've read were people recommend putting in 75W-90. What are the benefits of putting in the 75 verses the 80?

75w90 flows better in cold weather and might yeild a tiny bit more MPG too.