PourinDiesel

Its good oil, not synthetic.
I for one have not been impressed with full synthetics in heavy duty use....flame away!

Jeff in TD

No flaming. I'm sure it is good oil if it has the GL-5 rating, and it's your truck, so run what you want.

The book specifies full synthetic, though, so for warranty purposes that's what I went for.

2003Ram

On my first diff change, I ran a non-synthetic GL-5 for about 10k miles (1 1/2 years,25K miles -35k miles) before changing it to Amsoil.

From stock, to non-syn, back to full syn there has never been any difference in performance,noise, or mileage.

rustyshakelford

so are they going to knock me on my warranty? or should i just run it and switch to amsoil next change?

brett

PourinDiesel

Run it, thats my opinion. If your dealer gets down to using a fine tooth comb over warranty chances are they will find a reason not to warrant your truck (like not getting it changed at the dealership or something to that effect).

Overall the best thing you can do is keep your diff oil's changed(whether its syn or non syn)....its cheap insurance. Most trucks will not be serviced correctly hence the synthetic requirement. For those that change on a regular service interval non synthetic is just fine. But when it gets down to it synthetic will need to be changed on a regular basis also.

Stick with the 75w140 or 85w140 for max protection.

doug60

Schaeffers 75/140 here