2.9 > 2.3 Duratec Swap into a Bronco II 4x4

[Resident_Ranger]

Hey everyone, I'm looking for some thoughts on this. I have a cousin that had his Bronco II 2.9 over heat and crack the heads. Trying to find replacement has been not easy, so we are just running through ideas.

The Bronco II has the 7" running gear so swapping anything bigger becomes a total overhaul of the drivetrain. So the idea of swapping a 2.3 Duratec came up. It has similar-ish power numbers to the 2.9. What is the viability of this. I know we would have to mess with his transmission a bit to get the transfer case hooked up. But overall it seems like less messing around.

 

[pjtoledo]

sounds like a great project.
for wiring & computer get a donor 2005 year. that year only does not have PATS.
there are no 2.3 Duratec 4x4 transmissions. you can swap 3.0 tranny guts & tail housing to make one.

the Duratec does have stuff hanging on the back of the engine, may be firewall clearance issues.
avoid 2001-2003 because of the intake manifold flapper issues.

 

[bobbywalter]

yeah....the duratech is a potential monster.....you can shove 10 pounds down its throat and it will just take it.


in a ttb chassis its not so good though. with some lift or an sas its not an issue....but its much more fit-table in terms of easy then an ecoboost 4 whizzer.

i started the process some time back. for testing and fitment checks for ecoboosts...just no interest in it ...people just dont know i guess.

as mentioned you have to make a 4x4 trans for it.. i have used the 3.0 to do that.

 

[lil_Blue_Ford]

A 4.0 OHV is an easy swap for the B2. 89/90 are the really easy years to swap with a 90-92 Ranger donor or an early Explorer 91-94 since everything kinda matches up. The older B2s require a little more electrical work, but still relatively easy.

As for the rest of the drivetrain holding up, well…

The D-28 front that was in all but the 90 B2 doesn’t hold up well to the 2.9, and I’ve tried to make it live behind a 2.9 but I ended up swapping to a D-35 long before going 4.0 in my 89. Fun fact, if you’re swapping in a 4.0, the donor has the right axle and it pretty much just bolts in.

The 7.5” rear is more durable than a lot of people seem to think. I ran around with a 4.0 and 35” tires for quite some time and did not nice things to that rear axle until it finally got tired of my antics. Unfortunately the only way to put an 8.8” in is to cut off the spring perches from a Ranger axle and weld them back because the B2 has the leaf springs set about a half inch wider than the Ranger on each side. Still not a bad upgrade.

Somehow my FM-146 transmission just takes it. When it dies, I’ll probably throw a M5OD at it if I don’t have another FM-146 sitting around.

The BW-1350 has no complaints.