Want to install 13 speed, which one

A ten speed Eaton Transmission that is metric starts with the letters FRO.

 

Not really. To a small shop yes cause they can inspect it clean it up and sell it as a good used unit. But to the big boys its worthless just because the supply is so much higher than the demand. evidence of this can be found right here on ttr. Lot of threads asking about switching from a 10 to a 13. How many threads have you seen about switching from a 13 to a 10?

 

In my T 800 i have a RTLO18913A, if i remember correctly from a thread in here the A is a overdrive or double overdrive, can't remember though.

 

I googled it, and couldn't find out which it means. 13th is .73 for all current manual 13 speeds.

 

The last letter on the transmission denotes the step between gears and the gearing itself- ratio of low gear, Etc.

Certain steps (a, b, c, etc) are matched with certain engines to give you the best step between gears to get the most out of your engine.

 

The "O" indicates overdrive. An RTOO is double over for example. The A or B is gearset.