Ey guys. Went to the autopart store and asked them to look up the differential oil for my truck. They gave me the 75w-90. But I happened to look online and I see to use 75-140? Which one do I use?

 

for the rear it is Synthetic 75-140, if its a 4wd front is Synthetic 75-90.

 

The synthetic already has the additive? This is what I got:



So use this for the front ? It is a 4x4 .



It has the additive in it. Is that ok for the front?

 

There's no drain or fill plugs on the diff cover? How am I supposed to go about this?

 

There is a full plug in the side of the diff housing to drain have to take the diff cover off and reseal it with silicone

 

Ok thanks

I was at walmart gettin some stuff and I saw they had the 75-140 and the 75-90 for 10.95$. Is that too cheap? Go with Lucas?

 

me personnally i don't even use lucas or amsoil or any of that **** that is supposedly top of the line i use either the motorcraft oil or i use mobil one fluids for everything but even they supposedly have the additive i usually get it anyways and its always payed off for me

 

The front diff has a fill and drain plug in the front cover. Thats fine for the front. For the rear you will need a sythetic 75w140 for the rear and get 2 bottles of the Friction modifier additive.

 

What kind of test have you done that show its ****? We should compare my amsoil oil change at 5000 miles and your mobile one at 3000. After i started running amsoil i gained 1 mpg and my engine runs a lot smoother. no more wierd noises at -20% start. I think amsoil a very good oil. you go to any race event and 75% of the people are running amsoil or Lucas. you think they would run it if it was **** when that's how they make their money?

 

Well I saw a thread that a guy did and he said cheap stuff was fine. I plan on using Lucas tho. Cost more but u get what u pay for. It's never been done and with 165k on it I'm sure it needs it. Front and back