Hi -

New FTE member. I'm looking at a 1967 F750 for sale locally. This was allegedly a complete "restoration" by the original owner... except is has a different front axle, engine, trans, etc. Nothing wrong with that at all, IMO, and it seems like a really great truck! But I'd like to learn a bit more about what was there originally. I'm sure originally it was a gas truck and now it is a 3208 5-spd. But other questions such as it's an air-brake truck now, is that original? The rear 2-spd is an electric shift, does that seem original or swapped in? If the rear seems OE, what are expected axle ratios, etc.

VIN tag info:
F75FUA16660
174
J
F750
D81
H
7HD
225000
199
3800
212708

Thanks for any assistance!!!

 

Welcome to FTE! The following will be from the Master Parts Catalog for model years '64 to '72, A lot of it you already know, but doing it this way explains all the info for any viewer.


F75 = F750

F = 391 4V FT gas V8

U = Louisville Assembly Plant

A16660 = 1967 series number

174 = 174 inch wheelbase

J = Red

F750 = F750 22,500lbs GVWR

D81 = This is cab type and seat. My source is unclear for your year. If you have a Custom Cab, it will be clear from the chrome bits and door panels. Ditto a fancy seat.

H = Clark model 305V 5 speed direct transmission

7HD = 7H -- rear axle, I'll get back to you EDIT: & here it is courtesy of an old post from Numberdummy: 7H = Eaton model 17800 or 17801 Two Speed Rear Axle / 6.50/8.87 / 18,500 lbs. Rear Axle Capacity.
D -- Ford-Rockwell (Timken) front axle, 7,000lbs capacity

22500 = 22,500lbs GVWR

199 3800 = 199 net HP @ 3800 RPM, the power numbers for a 391 4V

212708 = 21 Atlanta District Code
2708 Domestic Special Order. Hard to say what all that was, as you have engine, transmission and axle codes, as well as a color code. So something other than those items.

 

It had a 2 speed as OEM, but those ratios are not diesel friendly. Is it good for more than 50MPH?

As to air brakes as OEM, Ford shows air brakes in the model designation and in axle codes. Your model F750 and your axle codes don't mention brakes. A model F756 shows air brakes for '64 to '67, I don't anything about special orders, so if air brakes were part of the special order, I can't tell you.

 

One thing to consider--what kind of wheels and tires are on the truck?

 

Nope - the owner states as much, that she’ll top out about 50-55. I figured that the ratios were still gasser ratios.

 

The OE bud style in the rear and more modern hub-centric 22.5s in the front. Tall tires, but still no speed due to the gearing.

As an aside, the air brakes are real sluggish to respond, both engaging and disengaging. I’ve driven air brakes a good bit before - wasn’t sure if that’s characteristic of the older design or if they need some maintenance.

 

Might be older wedge type brakes?

 

Awesome - thanks for this!!

I ended up purchasing the truck and am very excited about continuing the build. As stated earlier, the seller mentioned it'll top out about 50-55 mph. Well, on the way home I pulled out the GPS speed app - 50 by the speedo = 45 mph actual road speed!! So, yeah I'll definitely be researching options for trying to either re-gear the existing axle or swap in something that is more readily re-geared.

Ultimately I'll want to get it highway capable (65-70); so modern power train swap, gearing, and improvements in braking (i.e. more modern??). There is also a bit of steering wander and I haven't looked into that at all yet - unsure if these boxes have slack adjustment or if there is play in a rod end or similar.

I think the biggest issue will be brakes; looking for axles (front and rear) that can be swapped with more suitable brakes. I'm OK with air, but ideally, I'd love to go to a more modern hydraulic disc (F650-range) setup. I love the idea of a 2-spd rear and rough searching (before it was confirmed here the rear should be the Eaton 17800) that some rears have gear options in a 3.70/5.04-ish range which could be ideal.

But finding a 2-spd rear with that gearing and capable of hydro discs... I'm hoping that's not a unicorn of a rear axle to find or build. Based on what I can find for the rear would be the highwater mark for matching a front axle and brake setup.

So my searching is just beginning - if anyone has any insight, I'm all ears!!!

It's terrible weather out, but I'll post a pic soon.

 

(my previous reply disappeared... I hope this doesn't double-post)

Thanks for this!

I ended up purchasing the truck - I'll post a pic when the weather is so awful!

My main goal will be to get this truck highway capable - 65-70mph cruise speed. GPS confirmed that it actual tops out about 45 mph, currently.

I have done some light research (before learning this axle ID) and have seen gearing possible to as high as 3.70, which would be awesome. However, my other main concern is braking - I'd like to upgrade the brakes to a more modern system. I'm OK with air, but ideally I'd like to go towards a hydraulic disc like on F650s and I'd really love to keep the 2 speed functionality.

So I'm researching what will be possible to either modify what I have or swap in something that will be more easily built - I'm hoping that a 2 speed with highway gearing and hydro discs isn't an absolute unicorn to put together!

Then, the rear axle (braking system) will determine how I upgrade or swap the front axle.

I'm already learning that Rockwell RS172xx series looks like it may be a bit more modern axle series, just unsure how popular they were with discs. Otherwise, it looks like I can source R&P and even No-Spin diff parts if I needed to build one.

If anyone has gone down this road, I'm all ears!!

 

Swapping this thing over to juice brakes will be a real labor of love... I’d start by calling around to shops that deal in heavy truck transmissions, as they either build truck rear ends, or can point you in the right direction for someone who does. You’ll burn that 3208 right up if you run it too fast for too long; they were great in equipment applications, trucks not so much. You may have an easier time swapping a fixed ratio rear end in, and a different transmission to get you to highway speeds.

 

Why would you ditch the air brakes? At least parts are available and it works. Don't even consider doing the garbage Lucas Girling disc brakes that the newer trucks had up until 2000. Those are just prone to rotor failure. For your speed goals it would be cheaper and easier to swap the body onto a newer frame.

 

I did - they quickly talked me out of trying to find the unicorn rear 2-speed with the right highway gears. Hen's teeth was referenced...

I think with the axle changes this will sort itself out. Essentially, swapping in hydraulic disc axles with the right gears that I want is the lion's share of the effort. Then it's a matter of mounting the matching master and hydro-boost unit, run new lines, etc. That doesn't sound awful - I've done it before on a similarly sized truck.


"Works" is marginal. They are terribly sluggish to respond, especially when releasing, which makes predictability an issue - something you don't want at highway speeds. So even if it works as intended 50+ years ago, I'd have to imagine that newer technology is better. If I'm going through the effort of changing axles to get more appropriate gearing, then I'd definitely upgrade to modern brakes. At that point, I'd be happy with modern air brakes, but why? Hydro discs (out of an International, F650, etc.) will have all the capacity that I'll ever need. Plus it it much more predictable and less specialized if anyone else ever needs to drive the truck.

I'm not sure how - take-out axles (with the gearing, brakes, and air suspension that I'm looking for) appear to be had for a couple grand total. That's way less than a rolling chassis and effort involved in a cab swap and related fabrication. Not considering this chassis has been completely gone through in a cab-off resto, the bed is hydro dump hoist, etc. - I realize some of that may be new info, but I still don't see the 'expense' in swapping axles compared to acquiring a complete roller.