losifan94

I was thinking of swapping my lst transmission with a xxl transmission. However I don't know much about it other than it doesnt have the high/low selector. I was wondering:

• Does it give you more power and torque
• Does it give you more speed

Shem1

The XXL transmission comes with reverse but no hi/lo selection. The overall gear ratio is also different giving you a higher top speed with an XXL transmission. An LST2 transmission has an overall gear ratio of 2.09:1, and a XXL transmission has a ratio of 1.89:1. Specifically, this different ratio is due to the transmission output gears. These gears are called the F/R bevel gears. On a stock LST2 is the F/R bevel gears have 15/30 ratio while the XXL is a 16/29. This means that you do NOT need to use an XXL transmission to achieve the different gear ratio. You can simply replace the the F/R Bevel Gears in your LST transmission and it will be the same ratio as an XXL. In fact there is a kit for doing this if you are interested part number LOSB3119. So to answer your questions

Does it give you more power and torque? No, it has less torque.
Does it give you more speed? Yes, it has a higher top speed.

Hope this helps

Cummins Driver

iTrader: (19)

^^^ He said it.

Only thing is, its only about $15 more to buy the XXL transmission instead of buying the gears in your transmission. So iyt may be worth it to just buy the XXL tranny and have a complete backup/spare

Shem1

Yeah that's a good point especially since you can get them for so cheap from chop shops on fleabay