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  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 4.6L Mustang Tech

New Rear End Break process?

  • Thread starter Thread starter justin01gt
  • Start date Start date Mar 28, 2007
J

justin01gt

New Member
Aug 6, 2003
76
0
0
upstate ny
Mar 28, 2007
#1
  • Mar 28, 2007
  • #1
I am going to be finished with my new rearend soon and have heard a few different opinions on how to break it in correctly. One guy said run it with no stress (on blocks) twice getting it up to temp then letting it cool down, and then run it light down the road up to temp let it cool and your done. Another guy says nothing at all jus drive the car. And then a few inbetween there. Just wondering if anyone has an opinion on the matter?
 

four six

Member
Jan 19, 2006
506
2
18
Hobart, IN
Mar 28, 2007
#2
  • Mar 28, 2007
  • #2
If the gear is FRPP pull out of parking spot and launch


FRPP dson't need break in period
 

the98stang

Active Member
Aug 12, 2005
2,408
0
47
Clovis, CA
Mar 28, 2007
#3
  • Mar 28, 2007
  • #3
^^wrong

You need to wear in the pinion and gear properly but heat cycling the gears. Drive it on the highway @ 65 mph for about 20 min. Then let the car cool for 30 min. Do that process a second time, and the gears will be good to go. Better safe than sorry, right?
 

BurningRubber

10 Year Member
Dec 6, 2004
1,865
24
58
Mar 28, 2007
#4
  • Mar 28, 2007
  • #4
As per break in reccomendation for Summit Racing ring and pinions (not FRPP I know)...

After installation drive lightly for 15-20mi, park and let axl assembly totally cool down. After that do an easy 500 mi. with light loads.
 
S

smasher41

New Member
Feb 13, 2007
31
0
0
Mar 29, 2007
#5
  • Mar 29, 2007
  • #5
500 easy miles....You know how hard that is going to be? LOL

there will be more friction when new, as the gears wear into one another, so after some driving i would let it cool before going again.
 

Rickey_Bobby

New Member
Nov 8, 2006
332
0
0
Sarasota, FL
Mar 29, 2007
#6
  • Mar 29, 2007
  • #6
although not the preferred method, I bolted my backup diff/ring gear in after breaking it @ sebring and preceeded to finish the track event balls to the wall. It's still in there now 5,000 miles later.... no issues.

normally, 500miles of light load using Dino oil, then change fluid (synthetic rec.) Make sure you add friction mod when you change the fluid.
 
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