white cummins· Registered
I just purchased a 99 24v 2wd auto w/ 4.10 gears. I know I will have to change the rear end gears, but what eles will I have to due. Will I have to replace the ECM, speedo gear in the rear of the trans? I would like to change the rear gears to 3.55. I thank this would help with fuel economy. All the help is great. If you need more info., please just ask.