Stock body/engine harness and speedo

[papy]

Wondering if the 71 and 76 harnesses and speedometer gauge/clusters are the same for these year model broncos?
Thanks

 

[DirtDonk]

the clusters are virtually the same, while the wiring is different in lots of small details.
But both will interchange at most levels.

Just to be sure, your '71 has the wiring coming through a grommet on each side of the engine compartment, rather than two rectangular plugs in the firewall behind the engine?

The clusters swap over and the main difference is that the fuel gauge will say "unleaded fuel only" or words to that effect.
It's VERY possible that the back of the speedometer head where the cable enters have different interfaces. The early ones used a threaded collar and the later ones at some point used a plastic clip-on thingy.
They may, or may not work together. Not sure, but I bet someone has tried before.

The '76 wiring harness will have several additional wiring circuits, but the overall routing is the same as long as you have the routing I mentioned before. The changeover came at some point between '70 and '71, with most (if not all) '71's getting the new style.
The fuse panels are identical, but there will be a few more ignition wires, smog related wires, and maybe a bit more. Most of the changes were vacuum tube related, but some were electrical.

Wiring colors match. Wire routing is virtually identical, and body connectors are mostly the same.
The majority of engine connectors (ignition, charging, etc) changed in '73 to the newer style.

Basically it should all work. With a little bit of work...

Paul

 

[Steve83]

I don't have a '71 diagram, but this page shows '72:

(click this text)


'76 is on this & the NEXT 3 pages:

(click this text)

 

[DirtDonk]

Cool, thanks Steve.
Of all the later years, 71 and 72 probably have the closest to the same layout. 72 had a couple of extra things including the ambient switch system, but otherwise the layout was probably 95% the same.

 

[papy]

Thank you both for responding. I have a 72 body and found a 76 harness and speedo localLy here in Ab.

Also wondering if a speedo From a earlier 60's f100 will work with the bronco harness?

 

[Steve83]

You should put your location in your profile so it appears under your avatar & username.