just got the gears...break in period??

the98stang

Active Member
Aug 12, 2005
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Clovis, CA
Hey guys I just got my gears in :D . The guy told me to wait 500 miles before whompin on the gas. Should I really wait that long? I assume he knows what he's talking about...

He also said to change the gear oil after 1k miles. Should this be done?

I drove it around for half an hour, and now she's cooling off. Will that be enough of a break in period?

Thanks for the help!
 
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I beat on it right after i had mine installed. The guy who installed them deals with mustangs only and does a stand up job. He never told me to break them in or go easy on them for any period of time.:shrug:
 
Yes there is a break in period.
Some here will laugh at that, but they are wrong.
The new bearings, racers, etc. need to break in.
Go easy for the first couple of hundered miles.
Then change the differential fluid.
Then GO HARD!
 
I have seen gear break in threads go to six pages and have very heated debates.

Side one, the distance from the parking spot to the edge of the parking lot is MY break in period.

Side two, heat cycle three times and they are good to go.
 
03silverstang said:
I beat on it right after i had mine installed. The guy who installed them deals with mustangs only and does a stand up job. He never told me to break them in or go easy on them for any period of time.:shrug:

Yeah I had a mustang shop install mine as well. He said to take it easy the first 100 miles or so then do whatever you want to it and I'll never need to change the rear differential fluid afterwards. Told me all his FRPP gear installs went perfectly fine and never had one come back for whine or breaking. I don't have a problem trusting him either cuz he warranties all his gear installs. So if I do need something changed, its all done for free.
 
I also heard about the heat cycle or just do about 500 miles. When I got mine installed the guy told me to drive for about 30mins, stop let in cool down then do again 2-3 more times. I never stopped I just went easy for the first 100 miles or so. Never had any problems with them.
 
some say "do you need to break in the gears fron the factory?". I would go follow his advice, won't hurt to take it easy for a few hundred miles. better safe than sorry right?
 
I have had ALOT of first hand experiance with this, and I dont care what anyone says. Drive it for a few miles while weaving back and forth and varying speeds to make sure everything has oil and is oiled up, than NAIL IT. There is no 500 mile breakin, people just say that to cover their butts.

Basically you dont want to take it down the road doing 100MPH without sloshing plenty of oil around to lube the bearings. I personally like to wear the paint off the gears (only a few miles) and just for the heck of it, let it set and cool down. Then I go and tear it up :D. My opinion.

So go jump in your car right now, and feel the POWER :nice:. Youl love it.
 
Yeah, come to think of it, no one really goes through break-in procedures on the gears that come installed from the factory. Hell, any break-in procedure goes out the window because of those who test drove/owned our cars before we bought them.
 
40th GT said:
Yeah, come to think of it, no one really goes through break-in procedures on the gears that come installed from the factory. Hell, any break-in procedure goes out the window because of those who test drove/owned our cars before we bought them.
i really have to chime in on this thread b/c im a break-in nazi. EVERYTHING with moving metal parts has to be broken in. there is a reason for this. metal is like every other material, it expands and contracts based on it's tempurature. hotter=expanding, colder=contracting. the reason they say to do heat cycles is b/c you want the metal gears to heat up and allowed to properly expand and contract to ensure the strenth of the metal. heating them too much and for too long on brand new metal is bad b/c they might crack. the metal hasnt been "treated" yet. same thing with a new car. the metal in the engine; bearings, races, rods, pistons-they all need to break in easily by allowing to expand at higher temps and contract at lower temps. this is not :bs:, this is an actual science. in my engine building class one of my fellow students (who happens to drice a riced out civic-go figure) mentioned somthing about not having to break anything in and my instructor just laughed. then he proceeded to explain the science of treating metals for ~ half an hour. i didnt take notes, so half of it was forgotten. point is, EVERYTHING WITH MOVING METAL TO METAL PARTS NEED TO BE BROKEN IN.
 
My own car I beat on it almost instantly. I can't help it. I one of those peopel that HAS TO KNOW RIGHT AWAY how fast it is.

but for other peoples cars i suggest to give it a few hundred miles before riping off powershifts and such.

the biggest shock to the gears will be upshifts and launching so just avoid that for a few hundred miles.
 
hognutz said:
my .02

heat cycle the gears a couple times. but about 100miles on it. drain the fluid and make sure you have a good wear pattern. if everthing looks good game on. drive it like you would have before the swap.
that makes no sense....only if I had a bad install(which you could tell by driving the car) would i think about doing that. waste of time imo
 
DerekStangGT said:
i really have to chime in on this thread b/c im a break-in nazi. EVERYTHING with moving metal parts has to be broken in. there is a reason for this. metal is like every other material, it expands and contracts based on it's tempurature. hotter=expanding, colder=contracting. the reason they say to do heat cycles is b/c you want the metal gears to heat up and allowed to properly expand and contract to ensure the strenth of the metal. heating them too much and for too long on brand new metal is bad b/c they might crack. the metal hasnt been "treated" yet. same thing with a new car. the metal in the engine; bearings, races, rods, pistons-they all need to break in easily by allowing to expand at higher temps and contract at lower temps. this is not :bs:, this is an actual science. in my engine building class one of my fellow students (who happens to drice a riced out civic-go figure) mentioned somthing about not having to break anything in and my instructor just laughed. then he proceeded to explain the science of treating metals for ~ half an hour. i didnt take notes, so half of it was forgotten. point is, EVERYTHING WITH MOVING METAL TO METAL PARTS NEED TO BE BROKEN IN.

+1....:nice: