OK, the breakin is pretty easy for the rear end, but what about the front? It's not like we're going to drive 500 miles in 4wd!

 

For the front without unlocking hubs, the ring & pinion is only in coast in 2wd. I wonder if an easy dirt road ride in 4wd for 15-20 miles would break-in the front.

 

I was thinking the same thing. This gear break-in is a bit of a mystery to me. Until a couple of days ago I didn't even realize u were supposed to drop the fluid at 500 miles.

 

Don't get me wrong, if you or anyone feels you need to follow the break-in procedure, forget I said anything. I do know that when I asked about break-in, the installer told me that's a debate that's been going on for years. He said two schools of thought, break em in easy or drive it like I stole it. Anyhow he said if they come apart he'd fix it and anything it tore up, confident guy. I did have a t case and driveshaft issue afterwards, but the gears were perfect. Again, if u have the time to do the reg break in, do so just to be on the safe side. Me, well, I didn't have the time cause of my schedule, and with the gear guys info, I did what I did.

 

Still no advice for breaking in the front end?

 

I would think they'd get broke in enough just by driving in 2wd since they will be subjected to speed, heat.

 

What's the average running temp of a D44 rear axle? Reason why I am asking, is I installed some 5.13s over the weekend, then made 3 separate trips of about 20 miles and let them cool between each. I am now driving it back home, which is about 400 miles. After the first hundred, they are really hot. I assume they always run hot, just want to make sure im not burning them and breaking down the oil. Thoughts?

 

And it would be nice to hear what's the break in procedure for the front gears. Does the jeep need to be driven 4wd before changing fluid?

 

your still breaking in the gears for the front everything moves so its heat treating them just like your doing the rear i know there isn't a load on the gears but it will be fine. this is my second set of gears my first was on my tj and i have done this and no problems so i hope this helps

 

I'm not sure of the exact specs, but after mine ran at 75-80mph my rear diff was at 145-150 degrees farenheit, was told it was within spec. The rear is gonna be hotter than the front cause it's under load. And that rear diff is pretty hot to the touch.