Gears and Speedometers
Thread Starter
Intermediate
Joined: Dec 2006
Posts: 49
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From: Newtown PA
Gears and Speedometers
I'm going to swap my 3.42 gears for 4.10s in my 2009 manual coupe. Will this cause an incorrect reading on my Speedometer?
Also if I'm using my own core, can this procedure be done on the lift or does the entire rear have to be removed from the car?
Also if I'm using my own core, can this procedure be done on the lift or does the entire rear have to be removed from the car?
Former Vendor
Joined: Aug 2005
Posts: 16,897
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From: Lewisville TX
St. Jude Donor '03-'04-'05-'06-'07-'08-'09-'10-'11-'12-'13
You do not have to change anything for the speedo as the car picks up the pulse from the ring on the diff.
Auto cars would have to have it changed for shift points. You only need to change for tire size.
Mufflers have to be removed, it is easier to do with the rear cradle out of the car, but you can drop it down and slide it out. You do need to support the trans and torque tube of course as the diff is the rear mount for the drivetrain.
Auto cars would have to have it changed for shift points. You only need to change for tire size.
Mufflers have to be removed, it is easier to do with the rear cradle out of the car, but you can drop it down and slide it out. You do need to support the trans and torque tube of course as the diff is the rear mount for the drivetrain.
