My transmission(R4AX-EL) atf has to warm up before the transmission will shift into over drive. What problems could I expect, if any, allowing the transmission to shift to OD while the fluid is cool?
I have a 90 B2600i 4x4. Once on the highway I hate the way the motor has to run 500 rpms higher than normal waiting for the atf to warm up. When it finally does shift to OD the motor has been at normal operating temps for several miles. I have a 94 Pathfinder with a similar transmission and it also does this when cold. Imagine having to drive on the interstate with cool atf. And it makes my already mediocre gas mileage even worse. I'm wondering how the mechanical parts of the trans would handle an early shift to OD? I think I know of a way to bypass the atf thermosensor but am hesitate to try it.