Gear Break-in with FAD

[Bacon]

So I'm leisurely driving home from OK4wd breaking in my new 4.88 (JTR auto) and it occurs to me that my front ring and pinion aren't taking their relationship to the next level since I have the front axle disconnect.

As I'm sure that countless JLs and JTs have had aftermarket gears installed, I would imagine that this lack of break-in hasn't caused major issues on front axles.

This also got me thinking that auto manufacturers probably don't do any gear break in at all. If they don't do some automated miles with the axles out of the vehicle, they don't do anything. I've never gotten a new vehicle with more than a dozen miles on the odometer, let alone 500.

Thoughts?

P.S. I can't wait to get out of gear jail and lay down some rubber with all of this new mechanical advantage.

Sponsored

 

[Tim]

So I'm leisurely driving home from OK4wd breaking in my new 4.88 (JTR auto) and it occurs to me that my front ring and pinion aren't taking their relationship to the next level since I have the front axle disconnect.

As I'm sure that countless JLs and JTs have had aftermarket gears installed, I would imagine that this lack of break-in hasn't caused major issues on front axles.

This also got me thinking that auto manufacturers probably don't do any gear break in at all. If they don't do some automated miles with the axles out of the vehicle, they don't do anything. I've never gotten a new vehicle with more than a dozen miles on the odometer, let alone 500.

Thoughts?

P.S. I can't wait to get out of gear jail and lay down some rubber with all of this new mechanical advantage.

I can’t answer your question but I am curious about your experience at OK4wd. I‘m in NJ and will be looking into gears in another year or 2.

 

[Bacon]

I can’t answer your question but I am curious about your experience at OK4wd. I‘m in NJ and will be looking into gears in another year or 2.

I've been going to them for work on three Jeeps for the past 11 years. They are very competent and I wouldn't recommend anyone else.

 

[Renegade]

So I'm leisurely driving home from OK4wd breaking in my new 4.88 (JTR auto) and it occurs to me that my front ring and pinion aren't taking their relationship to the next level since I have the front axle disconnect.

As I'm sure that countless JLs and JTs have had aftermarket gears installed, I would imagine that this lack of break-in hasn't caused major issues on front axles.

This also got me thinking that auto manufacturers probably don't do any gear break in at all. If they don't do some automated miles with the axles out of the vehicle, they don't do anything. I've never gotten a new vehicle with more than a dozen miles on the odometer, let alone 500.

Thoughts?

P.S. I can't wait to get out of gear jail and lay down some rubber with all of this new mechanical advantage.

I’ve always wondered why there are break in conditions on new gears which aren’t applied to new vehicles.

 

[jc1986]

I’ve always wondered why there are break in conditions on new gears which aren’t applied to new vehicles.

It’s the same process, people just don’t do it and manufactures probably don’t care. New motorcycles are the same way. No exceed a specific speed or stay at a specific rpm for an extended period of time and go back in after 600~ miles for an oil change. Moto guzzis in particular since their rear drive is basically a shaft drive from a tractor, it’s a cool italian tractor (probably a Lamborghini tractor, I know it’s not). People should definitely change their gear oil long before most ever do. Just think about how many vehicles are out there that only get their motor oil changed…?

 

[CrazyCooter]

Perform the recommended break in for the rear gears and change the fluid. The front most likely will never be run enough to fully break in? Change the fluid in a few years after 100s of run in miles.

The big thing is the oil breaking down from the heat of the initial break in, then the metal left in the oil. After my 4 mile road test, I usually can't hold my hand on a rear diff cover. The first 25 miles is the most critical and then the first 25 miles that you tow after the break in.

For what it's worth, I have not seen a single potential warranty issue since I started shipping gear swaps with my favorite 75w140 synthetic oil (5 years ago) even if the end user didn't replace the oil. Prior to this practice, I had at least 2 per year come back whining about their recent gears being fried. They would come in swearing to me that they replaced the oil after the proper break in.......funny the oil looked clean and new? Where was the metal from the teeth being worn half way through?

 

[RodRecket]

I just finished changing the oil in the diffs after a gear break in. I did not do anything special for the front, maybe went into 4wd once or twice. I did notice that the rear diff oil looked much more "used" than the front, but that's how it's always going to be unless you live in 4x4.

Sponsored