This topic has been circumcised a good number of times.
In 20+ years of wheeling I don’t remember any wheeling buddy saying “Oh… I gotta break in my new diff gears.”
I know plenty of guys who installed new R&Ps, lockers, etc.
Are there millions and millions of vehicles manufactured, purchased and driven WITHOUT a “break-in”?
I realize gear manufacturers require/recommend a “break-in”. I don’t believe the recommendation has anything to do with requiring the mating surfaces to get happy. It is xxx times more likely to have premature failure due to improper installation, actual gear defects, lack of maintenance, neglect (deep water crossing and don’t change gear oil). The Break-In recommendation is a standard “warranty stipulation” thing.
In a front diff, for the average 4-wheeler, running on a trail all day (Rubicon), how much heat could those gears generate?
“The suggested break in procedure is as follows, The first drive with the new ring and pinion should be under normal driving conditions (No hard starts, No racing, No off-roading, No towing and not at Highway speeds). The vehicle should be driven 15-20 minutes around town, normal stop and go driving.”I have never known anyone who did this to "break-in" a new set of R&Ps, but I'm sure someone has.
https://www.revolutiongear.com/ring_and_pinion_break_procedureIf I were installing a new set of R&Ps I’d buy Yukon and buy their “no-questions asked lifetime warranty coverage” Extended Warranty for $49.89.
For a tow vehicle like a new Dodge RAM 3500, Dodge does recommend a 500-mile break-in before towing. That makes sense on a vehicle that can tow 37,000 lbs.
Gnarls.
