Break in gears?
5th Gear Member
Joined: Mar 2006
Posts: 2,652
From: Colorado
I was told stay out of it for the first 500 miles and vary the speed as well during the break in period.
So I hot rodded the heck outta it once or twice under the "vary my speed" advice and decided it really wasn't getting into it. Never had any problems.
So I hot rodded the heck outta it once or twice under the "vary my speed" advice and decided it really wasn't getting into it. Never had any problems.
3rd Gear Member
Joined: Oct 2004
Posts: 887
From: Arizona
The differential shop that installed my gears told me the first 50 miles not to drive over 50 miles.. After 50 go easy till 500mi. And no long trips to allow the heat and cool down process. After 500 anything is ok!!
3rd Gear Member
Joined: Oct 2009
Posts: 730
From: Utah
I had my 4.10s installed and then drove 150 or so miles home at highway speeds with a stop at Hooters for lunch. Drove it like a new car for two weeks afterwards and have had zero issues or whine and it's been since 2011
Ford doesn't say anything about heat cycling a brand new Mustang so I never understood the thought process behind all that.
Ford doesn't say anything about heat cycling a brand new Mustang so I never understood the thought process behind all that.
Gentleman's Relish
Joined: Feb 2005
Posts: 13,189
From: AZ
Just because the OEm doesn't say anything about it doesnt' mean it's not important. Ford says ZERO (as do all domestics) about regular intervals for changing brake fluid yet you should replace it every 3 years/36K miles just like antifreeze and power steering fluid. European cars have had it in their books for years.
Break-in period strengthens the gears (heating/cooling cycle), and creates the wear pattern that will make the gears quiet. (Like bedding brakes). Since we're talking about hardened steel/metal the break-in period (bedding period) is considerably longer than brake pads.
Some don't do it, others do. I will when I get my 3.73 installed.
Break-in period strengthens the gears (heating/cooling cycle), and creates the wear pattern that will make the gears quiet. (Like bedding brakes). Since we're talking about hardened steel/metal the break-in period (bedding period) is considerably longer than brake pads.
Some don't do it, others do. I will when I get my 3.73 installed.
3rd Gear Member
Joined: Dec 2006
Posts: 944
From: Colorado
The Ford Racing intall sheet said three 30 minute non spirited drives
with cool downs.
I drove back and forth to work for five days, so that was ten
heat ups and cool downs. Probably 200 miles for those five days.
Nice & quiet.
with cool downs.
I drove back and forth to work for five days, so that was ten
heat ups and cool downs. Probably 200 miles for those five days.
Nice & quiet.
2nd Gear Member
Joined: Dec 2011
Posts: 180
From: CA
you need 3 cycles to break them in, where you'll need to go easy on the clutch and don't go over 65mph.
by cycle people usually refer to something similar to a 10-20miles / 15-30 minutes drive, and then a cool down period of 2h.
