The rear end in my 2001 has been replaced before I bought it. The tag has the following letters and numbers. S229H SL28 88 0H10. Can anyone ID what gears the car has?

 

The SL88 MAY BE 5L88

 

From what I understand, the L in "#L##" means Trac-Lok, and the other numbers in that part of the code should represent the gear ratio. But those numbers don't sound right. Maybe try reading it again?

But hey it is a Mustang after all, so there's no guarantee that somebody hasn't changed the gearset inside. Only way to really be sure of the gear ratio without opening it up is to count driveshaft revolutions vs wheel revolutions.

 

You were right about rechecking the numbers. They actually say 3l27which I see means 3.27 gears. Don't know where I got 5l28 from.

 

 

The tag will tell you what gears were installed at the factory. It will not tell you if anyone's changed them since.

 

 

 

You are correct. DD is the code for 3.55 rear axle.