Best gear oil for rearends?

The manufacturer recomends a certain grade oil, it is like that because the oil is made to flow in a certain way to lubricate the components, when you change the oil weight you change the flow patterns, when you add junk like lucas. you risk a lot.
I worked at a truck dealership the gear guy called me over one day to show me an 18 speed that failed the oil was jelly, the gears were burnt, the eaton rep came over, spent 2 seconds looking at it and denied warrenty. the whole unit was junk even the case, he bought a brand new transmission because he was told Lucas was great stuff.
I buy the very best oil as per manufacturer recommendations no additives unless recommended
Just a thought!

 

Eaton and Meritor recommends 75w90 for typical set of drive axles on most trucks except heavy haul. Sometimes heavier for more sturdier weight axles. I have used nothing but 75w90 synthetic for about 20 years. My current ride came from the factory with Mobil 1 synthetic 75w90. Since both Eaton and Meritor will extend the normal 500,000 mile warranty to 750,000 mile warranty if one uses synthetics, that must mean something. I change mine out at around 300,000 miles, though the recommended drain interval for synthetics in my drives is 500,000 miles. Never had anything more than a hub seal go bad on any axles.

Agree with John. No additives needed. Everything those gears need is in the lube already. There are any number of good brands of lube to choose from.

 

I also recomend you buy an extra 3/4 NPT magnetic plug and do a plug swap on all the drain plugs in the transmission and rear gears, It gets the little bits of metal out of the system. it is especially important to be doing this before the warrenty period of the different components. also be sure you check the vents are open.
If you have a 750,000 mile warrenty you want to change the oil at the 1/2 of that 375,000 miles, and do the change at the dealership to get the warrenty ensured. also if you get it changed before the warrenty ends and they find a spider bushing it is repaired under warrenty.
I worked at Freightliner you could get eatons own oil or anyone elses you wanted.
Just a thought!

 

I wonder how many days the typical Freightliner dealership will make one wait to do a fluid change on the driveline?

 

I am getting ready to change mine as soon as the snow melts & going with Schaeffer. The only thing of theirs I did not like was a transmission fluid, but that was for a diesel p/u. But will definitely cost more than the free 220, up front anyways.

 

Schaeffer is a solid product. I use their oils and lubes in my trucks and ag tractor.

 

Just had a guy convince me to add 1qt of lucas hub oil to my diff which is filled with FE75/90. Should I run to have it drained?