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  • 2005 - 2014 S-197 Mustang -General/Talk-
  • 2005 - 2009 Specific Tech

Rear End Gears

  • Thread starter Thread starter pjk
  • Start date Start date Jan 2, 2012
P

pjk

New Member
Jan 1, 2012
8
0
1
Jan 2, 2012
#1
  • Jan 2, 2012
  • #1
How can I determine what gears Are in my rear axle? I think there not stock because the speedometer is wrong.
 

SpartaPerformance

10 Year Member
Nov 5, 2006
2,517
61
89
Long Island NY
Jan 2, 2012
#2
  • Jan 2, 2012
  • #2
Ask the previous owner, or pull the diff cover off and check the stamping on the ring gear.
 
P

pjk

New Member
Jan 1, 2012
8
0
1
Jan 2, 2012
#3
  • Jan 2, 2012
  • #3
Thanks for the info. If I can't find another way I will pull the cover, but the oil is new. I bought the car from a dealer so I cant ask the previous owner. I thought there was some way to see what RPM at a certain speed?
 

SpartaPerformance

10 Year Member
Nov 5, 2006
2,517
61
89
Long Island NY
Jan 3, 2012
#4
  • Jan 3, 2012
  • #4
If you have access to a lift and you have a good eye here is a good way to do it. Roll the rear wheel so the valve stem is straight up, then chalk a horizontal line on the drive shaft, spin the wheel and count how many rotations the wheel makes for one shaft revolution.
 
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