Will my 5 speed bolt up to my old 4 speed bell housing?

 

You need to post more info, yr truck, model, engine, 4 spd trans, 5 spd trans, 2X4, 4X4

 

66 F 350 5:13 rear gears 2 WD

 

I'm guessing by 4 speed you mean a NP435 so I copied below the approximate dimensions from the Novak website. It's not all the info you need to confirm fit but it might eliminate whatever 5 speed you have.

I'm curious why you want to switch? The 5 speeds I've seen don't have as wide of a ratio as the NP435 but you obviously get more intermediate gears which help when towing heavy.

The Ford NP435 has a 1-1/16" diameter, ten spline input shaft that has a stick-out of 6-1/2" from the front face of the transmission. The pilot tip of the transmission measures ~17mm. The front bearing retainer flange measures 4.85" and the bearing retainer tube is 1.43" in diameter. The front bolt pattern is the symmetrical Ford "butterfly" pattern; roughly 8-1/2" wide by 6-5/16" tall.

 

I-6 or V8?

 

thanks I will have to do some more research on my trans.However you brought that to my attention.Now I am thinking how I plan on using this truck.I will get back to you in a few days as my project is 25 miles from here. Dan

 

What engine does it have?