No one can say with any certainty... you'll have to draw your own conclusion based on the best available information and your own direct observation and inspection. We can only assist in so far with informational resources and our own personal experience/knowledge.

 

Thanks for the reply. While at the yard, I took a few pictures and it appears that I captured the 73-79 radius arm (right side suspension)

 

In this photo from Fordification, it says the notched radius arms from the Dentsides were for the '73-'79 models or, "some" '73-'79 models.



The notch in the forward end of the radius arm is for the locating pin on the Dentside sway bar endlink C-bracket to engage with (pins shown on C-brackets in photo immediately below). The forward-mounted factory sway bar didn't become available on the Dentside F100s through F350s until 1975 ('75-'79).







Sway bar endlink C-bracket on my truck. (you can also see part of the D5TA casting on the '77 F100 I-beam on my truck).






I haven't (knowingly) seen a '73/'74 radius arm to observe if this is true or not but, by reason of deduction, it would seem plausible that if the forward-mounted sway bar didn't come out until 1975 that there wouldn't be any notches at the forward ends of the radius arms on the '73/'74 models.

I notice in your photos the notches can be seen on the front end of the radius arms. If my theory is correct, you would have the disc assemblies from the later model '75-'79 F100/F150.

 

Fantastic information on this thread. I am going to see if I come across a 73 or 74 truck (seems like the most straight forward) unless someone here has tried the swap that I was considering and was able to accomplish it without any problem or major modification.

Anyone that may have a need for the disc assemblies that I picked up, let me know.

 

Where are you in CA? I've got a set of spare '78 beams compatible with those disc assemblies.

 

Yep. So Cal.

Do you have radius arms as well? What do you need to have for the parts and are they in need of new bushings?

 

I just came across a 78 f350 with 8 lug rims at one of the local salvage yards by me. Are the I-beams and radius arms from the F350 compatible with the disc brake assemblies that I pulled?

 

Darn. I'm in the SF Bay Area. You should be able to find a set in SoCal... it's autoheavenn down there.

Needs pivot bushings just as a matter of routine.. No radius arms... I used 'em on my 70.

 

Sorry for the double post. I located a 78 F350 and was wondering if the I-Beams will work from that vehicle on the 75-79 disc assy?

 

No. '75-'79 F250/F350 would have a 1.05" kingpin diameter.'75-'79 F100/F150 kingpin is .859".

The beams will have to be from a '75-'79 F100/F150 to be compatible with the discs you have.

 

Where in So. Ca. are you?
If I see any later beams at the yard I'll give you a heads up.

 

Not far from Los Angeles

 

I am posting 2 photographs of the proportioning valve off of the donor truck. I cleaned it a bit and it appears that the engineering number on the valve is C8TA-2857-M. Was this proportioning valve original to the truck or was a "C8" number used in the 75 through 79 trucks? In other words, I am wondering if the the valve was not replaced by the owner of the donor truck when he swapped out the brakes? Maybe that is why the truck had substantial front end damage.

Does anyone have the part number/engineering number of prop valve that is correct for 75-79 trucks?

 

Not a proportioning valve. It is a pressure differential valve. It was used on ALL '67-'72 F100-F350 with all-wheel drums or, with optional discs front/drums rear on '68-'72 F250/F350 --only difference being the brake warning switch: '67 had one wire, '68-up had two wires and, a factory disc/drum F250/F350 would have had a separate metering valve plumbed into the front brake circuit.

An all-wheel drum brake Bumpside would not use metering or proportioning. It would just have the pressure differential valve that you have pictured.

The pressure differential valve pictured was stock to the '69. The person that swapped the Dentside front discs onto the '69 donor truck did not change out the brake valve.

If you're going to use a factory valve, you need to pull one from an actual Dentside truck or, locate an NOS Dentside brake valve for discs/drums.

 

I learn something every day. The C8 number clued me in that the part was probably not right for the job. Does anyone have a part number for proportioning valve?

I would imagine that the donor truck (69') brakes were not working optimally when it crashed, sending the truck to the salvage yard. What is the effect, if any, if you don't add a proportioning valve--rear brakes locking up or possibly a number of other braking failure issues?

Or, can I get away without changing the pressure differential valve without any concerns.