170 I6 5 speed tranny swap?

[Dealercut66]

I did some searching and couldnt find any info on a transmission with overdrive for a 170 I6. You all know of any swaps that work? Preferably without any cutting of my Bronco? With the no cutting in mind, I would think an automatic tranny would be the ticket.

 

[broncnaz]

One that may work and wont set you back a lot of $$ is the toploader 4 speed OD tranny that came in some late70's trucks and vans it came in a few cars to. OD is rarely done in EB's with the 6 cyl especailly the 170 because it just doesnt have the torque to benifit from the OD(about 150 ft lbs) theres a reason the factory put low gears in the 6 cyl broncos. I believe you could do a NV3550 swap as the bellhousing to transmission bolt pattern is the same between 6 cyl and V-8's.

 

[Dealercut66]

Thats kinda what I was thinking about the available torque. Too bad as I am still not wanting to cut up this Bronco. Back to the search...

 

[Broncobowsher]

In theory, the NV3550 should work. Since you are dealing with a 6 cylinder, you will be out of the norm. You will have to adapt most everyones thoughts on V8 into the 6 cylinder world.

Since the 6 and 8 both have the same bolt pattern where the trans bolts to the bellhousing, and the same input splines. (as proven by countless people who did bad V8 swaps keeping the 6 cylinder trans) If there is a transmission that will bolt to the stock V8 bellhousing, it should bolt to the 6 cylinder bellhousing. AA makes a kit to adapt the NV3550 to a V8 bell housing, so it should work on the I6 with little changes. You will have to move the transfer case back a little and change the driveshafts. And no matter what you will need to cut a hole in the floor for the shifter.

If you are looking at automatics, I remember some good tech stuff at http://www.fordsix.com/tech. But I think the I6 would be better suited to a manual transmission in a Bronco.

 

[Dealercut66]

Good info, I hadnt made the connection that ppl put V8's in Broncos and left the small 3 speed from behind the I6. However, the only reason I would put in a tranny swap behind the I6 would be to not cut the tunnel and keep it as uncut as possible. If I went with the NV3550, I would stick a V8 in at the same time.

 

[Broncobowsher]

OK, if you don't want to cut the tunnel at all. Your only option would be an automatic. No other trans option lets you keep the column shift. You would still probably need a body lift as the transfer case would be shoved back and probably hit the tunnel behind the hump.

A 5 on the tree would be so interesting to see someone build.