2.9 Liter Engin Swap for 4 CYL

[jeffreymiller80]

Has anyone swapped out a 2.9 L for a 4 CYL? My son's 1990 2.9 L is leaking oil and I am wondering if I can replace it with a 4 CYL and if he would get better mileage. He currently get about 15-17 mpg. Alternatively, would I get better mileage with a rebuilt 2.9. The trany is a automatic with overdrive.

Jeffremiller80

 

[dangerRANGER89]

i would also like to know this

 

[Big Red Ranger]

ya my buddy did it due to raising gas prices and it was a little difficalt but it runs great. if it is a 4x4 dont expect much better gas milage and if it is two wheel drive it will get better.

 

[Mark_88]

Has anyone swapped out a 2.9 L for a 4 CYL? My son's 1990 2.9 L is leaking oil and I am wondering if I can replace it with a 4 CYL and if he would get better mileage. He currently get about 15-17 mpg. Alternatively, would I get better mileage with a rebuilt 2.9. The trany is a automatic with overdrive.

Jeffremiller80

I did this swap but I just pullled the tranny and motor out and dropped in the mounts for the 2.3 (the frame is already predrilled for this). Only thing about my swap that may be different is I had already removed the cab and box so I had plenty of room for adjustments...but it can be done with the cab on...of course!

the only other problem I had was the driveshaft...I went from a regular cab to an extended cab and the 2.9 driveshaft does not work with the spline on the tranny...you need to change the driveshaft or mod the splines to work...