Fluid changes after regearing

Hey everyone. I got my gears changed out for the nitro 5.29s a few weeks ago. I'm coming up on my 500 mile break in, and as luck has it, I'm stuck changing the fluid out myself.

The guy at the shop gave me the impression (or I understood him wrong) that I do NOT need to change out the front fluids from the differential. Is this correct? Or should I do both the rear and front on Sunday when I hit 500 miles?

Thanks!

 

Did you stick with the stock open carrier up front? Have you spent any time in 4wd?

If you still have the open carrier up front and have been in 2wd the gears in the front yet haven't even been spun, so there is no break-in that has occurred. Once you get some time actually using the front gears, you can consider them broken in and then change the fluid to check for issues and flush out any break-in debris.

 

Hmmm what do you mean by "open carrier"? I'm new. hahaha.

So, they say 500 mile break in period for the rear, which includes no highway speeds, no fast acceleration, no off-roading, pretty much grandma driving for 20-30 minutes at a time before letting the oil cool down. Will I have to do the same thing for the front in 4 wheel drive for 500 miles?

 

Open carrier meaning you have the stock differential and didn't install a locker at the same time. You do not need to be that exact in breaking them in. They just need some non-severe use for a little while. Basically, at first, avoid prolonged hard use and get in some cool down cycles. All you're looking for is some load to polish in the contact faces and avoiding extreme temperatures.

 

I appreciate the responses. I assume I should change out the front dif oil after I've done that little break in period?

 

That would be standard procedure, yes.

 

Just to clarify even if you drive thousands of miles without ever turning on 4wd you wouldn’t have to change out the front fluids? Until you get some use in 4wd?

 

Not exactly. In 2wd the spider gears of the differential are spun. They are not under load and basically free spinning, but will generate some heat. It's just that the ring and pinion, pinion bearings, and carrier bearings are static. So without 4wd you aren't using or breaking in the bearings or the ring and pinion, but you are generating some heat and wear in the spiders and thrust washers from them spinning freely.

 

I see, so when does the front diff fluid get changed?

 

Rip

 

Whenever you want, at the suggested interval, or when it gets water in it. I just do it when I do the rear because it's less than 2 quarts.

 

Awesome thanks for all the info sir!