Hash06

my 4.10s are being installed as i speak and i was wondering when i get it back will they need any break in time before i use them to the fullest

so1o2k3

not sure exactly how long, but I would say at least a week of normal driving around. (and no not normal for most of us on here, normal as in most of the people who don't own sports cars)

monkeydude3

few hundred miles would be good

gary96gt

absolutely, i just got my 3.73's about two weeks ago. some people have said two different things

some people say X amount of miles from as low as 100 to as much as 500 before gettin on it.

my guy said it needed to heat cycle. he said let it heat cycle 5-10 times before getting on it.

heat cycling is: get it up to running temperature and then letting it cool. i broke mine in over about a 3-day period. i not only heat cycled it about 10 times but i also put about 250 miles on it. and mine are perfect. gears are great!

monkeydude3

when I rebuilt my trans, I drove it 500 miles worth of general cruising, stop, go, accel, decel etc etc and then changed the fluid (Found some metal particles off the broken in synchros) and put in fresh fluid. Trans loved it

I know the rear end is different, but it should receive equal treatment

OldSkool

i would just drive it normal for a few days, just in case. it seems to me that the splines on the gears would have to get worn in just a little bit.

03sonicgt

I've heard you should drive normal for 30 minutes, let the car stop and cool down for an hour, then repeat the process two more times.

wwmost

yup its all about heat cycling.

GodAmGT00

I've put almost 25k on my rear axle, and never broke it in.. When I had the rear cover off last week, the entire rear end looked practically brand new.. No signs of ANY wear...

I think since gears are forged, and pretty strong as is, it shouldn't make a difference.. Just make sure you have the diff. filled w/ the correct mix of Friction Modified and gear oil...



JT

rbstang

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