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Is there a break in period for new rear end gears?

  • Thread starter Thread starter jrc_03_gt
  • Start date Start date Jun 18, 2004

jrc_03_gt

New Member
Jan 1, 2004
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Jun 18, 2004
#1
  • Jun 18, 2004
  • #1
I have heard both yes and no. I want to know what everyone has been told that has them. Is there a general break in period? Can I go ahead and roast the tires ? I only have about 35 miles on the new ring & pinion. Or should I just take it easy for a while?
 

Cobra Jay

Member
Apr 7, 2004
889
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Motor City
Jun 18, 2004
#2
  • Jun 18, 2004
  • #2
jrc_03_gt said:
I have heard both yes and no. I want to know what everyone has been told that has them. Is there a general break in period? Can I go ahead and roast the tires ? I only have about 35 miles on the new ring & pinion. Or should I just take it easy for a while?
Click to expand...


100-150 miles should be plenty. The black finish on the gears is put on after they are lapped to make sure that the axle lube sticks to it for break-in.
 
B

bdcardinal

tree hugger
Jun 10, 2003
3,612
16
69
santa barbara, CA
Jun 18, 2004
#3
  • Jun 18, 2004
  • #3
i heard that you take it easy for the first 500 or so miles, then drain the fluid and refill with synthetic and youre good to go.
 

GoBabyVroommm

Active Member
Mar 22, 2003
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Chicago, For Realss???!!!
Jun 18, 2004
#4
  • Jun 18, 2004
  • #4
LOL drove it one block, i let everything get lubed up and hit it. Never had a problem with it. People that i know that usually do the breaking in there gear whins.

I'm not saying its cause they break it in, its because the install was bad. If you gear is install good your set to go. Some gears do whin but mine don't because i went with the Ford Racing.
 

Dark Knight GT

I can't get it up......ok that didn't sound right.
May 26, 2003
3,653
2
56
Ozark, Missouri
Jun 18, 2004
#5
  • Jun 18, 2004
  • #5
bdcardinal said:
i heard that you take it easy for the first 500 or so miles, then drain the fluid and refill with synthetic and youre good to go.
Click to expand...

 

Cobra Jay

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Apr 7, 2004
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Motor City
Jun 18, 2004
#6
  • Jun 18, 2004
  • #6
GoBabyVroommm said:
Some gears do whin but mine don't because i went with the Ford Racing.
Click to expand...


Stock gears sometimes whine, and FRPP gears are made at the same plant. Maybe you're just lucky!
 

Modular2v

Founding Member
Jun 30, 2002
3,222
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99
oklahoma
Jun 18, 2004
#7
  • Jun 18, 2004
  • #7
drive easy the 1st 5o miles, then let them rip.....you dont need to change the gear oil either
 
9

98GtRioRed

New Member
Dec 7, 2002
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Jun 18, 2004
#8
  • Jun 18, 2004
  • #8
I broke mine in backing down the driveway....then ZOOM!!!
If the install is correct no break-in needed as stated above.
 

mpcv2000

Active Member
Jul 29, 2002
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Montreal , Quebec !
Jun 18, 2004
#9
  • Jun 18, 2004
  • #9
I got my gears in at 5.00 o'clock and I was at the track at 7.00 , the break in period was from the shop to the track...


This was over a year and a half ago...
 
B

BLUE03GT

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Jul 13, 2003
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Sunnyvale, Ca.
Jun 18, 2004
#10
  • Jun 18, 2004
  • #10
i heat cycled the gears for the first 100miles then took it easy for another 300 and then let it rip... i wasnt taking any chances... and they turned out great.. no whine at all! .. Motive 3.90's!
 

jrc_03_gt

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Jan 1, 2004
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Jun 19, 2004
#11
  • Jun 19, 2004
  • #11
BLUE03GT said:
i heat cycled the gears for the first 100miles then took it easy for another 300 and then let it rip... i wasnt taking any chances... and they turned out great.. no whine at all! .. Motive 3.90's!
Click to expand...

I was told to do that by my installer too! (Heat cycle) Dont know if I can wait the 300 miles though.
 

BrightBlue00GT

I am even OLDER than Hawk!
Jun 22, 2000
2,906
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47
Stationed in Korea
Jun 19, 2004
#12
  • Jun 19, 2004
  • #12
Holy Crap! No wonder so many people on so many forums have complaints about gear noise. With as many ways to break in (or not) on this thread alone will tell you why.

You must heat cycle gears, about 50 miles will do (although it is recommended 300-500), change the oil and CHECK FOR CONTAMINANTS, add another bottle of friction modifier and then you're good to go. Heat cycling preps the material in a way that can't be done prior to install because the manuf can't actually mesh the gears the way your rearend will.

A "good" install does not compensate for heat cycling the material. Besides, if you have anything other than a good install, you already have problems.

All gears have the possiblity of whining; it's not the gear material (brand), it's the install.

"Lubing" up the gears isn't why you break them in and is not a substitue for heat cycling the material, although they do need lube and are coated after being lapped to ensure oil adheres during the heat cycling process.

jrc_03_gt - those who have not had problems yet are just part of the lucky crowd. Do yourself a favor and just do it.
 
S

slow87GT

Founding Member
Jun 5, 2000
162
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0
Tonawanda NY
Jun 19, 2004
#13
  • Jun 19, 2004
  • #13
mpcv2000 said:
I got my gears in at 5.00 o'clock and I was at the track at 7.00 , the break in period was from the shop to the track...


This was 2 weeks ago...
Click to expand...
 

Jackie Chan

I didn't read this.
Founding Member
Oct 17, 2002
2,507
4
48
Orlando, FL
Jun 19, 2004
#14
  • Jun 19, 2004
  • #14
blah, blah, blah....2 different sets of gears here, no break-in, and no noise. every car from the factory gets heat cycled right?
 
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