ls1m6nichols

iTrader: (2)

i just installed a 12bolt detroit true trac with a 3.90 gear 30 spline how many miles do i need to keep it easy on it or how should i break it in
Thanks

MeentSS02

iTrader: (11)

New gears (as in not run before)?

New gears generate lots of heat during run-in, and that tends to be what causes issues. When I asked this question in the past, I was told 10 total heat cycles (full warm up to full cool down), change the oil, then go for it. For the warm-up, they recommended a full 30 minute or so drive including at least some highway driving to get everything up to temp, and for the cool-down, let it sit all day or overnight.

ls1m6nichols

iTrader: (2)

Will a new gear whine a little and quiet down when worn in
Thanks

marubsls1

i was told easy on it for 500 miles then change the fluid then you can get on it hard stange 12 bolt 4:11s posi

MeentSS02

iTrader: (11)

If it whines now, it will probably always whine. The new gears in mine whined loud right from the start, and are still just as loud if not louder.

marubsls1

If it whines now, it will probably always whine. The new gears in mine whined loud right from the start, and are still just as loud if not louder.

Mine was just like that I had pro gears n switched to street gears n the is no whine

ls1m6nichols

iTrader: (2)

Thanks Yall
What kinda oil do Yall run?

Bob@BruteSpeed

iTrader: (16)

80/90 weight non synthetic. Bob

1972camarols1

80/90 non synthetic