Twin I Beam Evolution

[Francy Boy]

Hey, anyone know how the Twin I Beam suspension changed over the years? I'm under the impression that they remained the same for the most part (with some minor changes in kingpin sizes maybe?) at least until '79. Is that true? Was the design altered from 1980 forward?

Thanks for the help.

[Ranchero50]

Yep, bumps and dents are interchangeable as long as you stayed F100 or F250 / F350. '80 and up did there own thing with the wider frame.

[Francy Boy]

Thanks for the info. I'm looking to put front disc brakes on a '66. I was hoping I could pull some parts off of a newer truck (easier to find), and install them onto mine. Looks like '79 will likely be the last year model I can steal from, huh?

[radioactivelarry]

Thanks for the info. I'm looking to put front disc brakes on a '66. I was hoping I could pull some parts off of a newer truck (easier to find), and install them onto mine. Looks like '79 will likely be the last year model I can steal from, huh?

Here is a site to check out about disc brakes for F-100's Their kit uses brackets that use newer year components and a lot easier to install. You don't have to remove the suspension, just upgrade the rotors using your front hubs (just remove the drums) and it uses GM calipers with the right parts.
Fits F-100 from 65 - 67. https://scarebird.com/index.php?route=p ... uct_id=155

This kit fits 68 - 72 trucks. https://scarebird.com/index.php?route=p ... uct_id=149
They also have kits for a bunch of cars also.
Good luck.....

[Francy Boy]

That's sweet. Thanks.

[NM5K]

Pretty much the same as I recall.. But my 74 is a F100, and the 68 is a F250. But the design is still
the same, except that Ford went to the nylon bushings on the dents.. That's one difference I can think of.
The 74 I have, it's already had those changed once, and it needs them again. But I haven't been driving it,
so hadn't worried about it.
When I overhauled the F250 front end, I used bronze bushings and had a place ream them out for a good fit.
I expect a good bit longer life from them vs the nylon.. As long as I keep em greased anyway.. Which reminds
me, I need to do that. Need to change my oil too..

Both mine have the same engine block too.. A 240 in the 74, and the 300 in the 68.. So under the hood
isn't much difference either.