I will be swapping in a 78/79 High Pinion Dana 60 into my 75 crew cab that currently has a low pinion D60 in it. I'm probably way over thinking this so I have a few points of clarity that I'd like help with. Questions in bold:

The truck that this will be going into is a 1975 F-250, 7700 GVW, crew cab, 4x4 with manual steering, currently 4 wheel drum brakes, a 390 FE motor and C6 automatic transmission. I currently have a Skyjacker 4" lift with 35" tires and am using the stock pitman arm, draglink and steering arm on the low pinion D60. Other than it being manual steering, my truck drives very well in its current configuration with no bumpsteer. The old adage "if it ain't broke, don't try to fix it" is going thru my head... I worry that this axle upgrade could introduce some new steering problem, but a little fear shouldn't stop me from jumping in.

Here's the current steering setup:


Do I need a different pitman arm, drag link or steering arm for the high pinion D60? (I believe the answer is no to all 3)

The steering arm on the high pinion dana 60 is broken. Can I pull the steering arm off the low pinion D60 and put it on the high pinion?



I'm a bit confused on what is required to change in the brake system.

Here is the brake pressure differential valve I have on the truck today with all drum brakes.



Since the front brakes are going from drum to disc I acquired a proportioning valve off a 78 F-150 that has front disc and rear drum brakes. It's really dirty:



Based on reading some posts from ultraranger... (reference link)


I know I'll need to possibly redo some of my hard brake lines and replace my front soft brake hoses.

Option 1: Do I completely eliminate the brake pressure differential valve and replace it with the 78-F150 proportioning valve?

Option 2 Should I look for a 6900# or greater GVW brass Weatherhead brake proportioning valve off a F250/350? (I found a truck nearby I can pull one off of)

Option 3: Do I keep the brake pressure differential valve and add an aftermarket proportioning valve such as this one plumbed into the rear line?

Option 4: Do I keep the brake pressure differential valve and add a pressure differential brake valve such as this one into the front disc brake circuit?

Option 5: Buy this valve from JBG. (Not the cheapest route but gets me a new, correct piece)

If I did option 3 or 4 would I need the 78-F150 or higher GVW proportioning valve for the front disc brakes to bleed properly?
(this is obviously a mute point if I go with option 1 or 2)

I plan on upgrading to hydroboost brakes in the future. How might this factor influence the option I take above?

To improve ground clearance I know I should flip my ubolts. I will purchase new plates to hold to leaf spring from WFO Concepts or ruffstuffspecialties.

WFO Full kit ($84.99) includes one 4"x10"x5/8" u-bolt & three 3.125"x8"x5/8" u-bolts w/all nuts and washers. Mfg site says "You will need to notch your axle housing on the lower rib, in order to keep the large u-bolt from sliding... This kit requires some grinding on the lower lip of the housing to allow the large u-bolt to fit."

Does anyone have a suggestion for the ubolt flip besides one of these kits or making my own plates?''

Thanks!

 

The first question would be what are you trying to accomplish by swapping in the newer axle, meaning is it justified? I would think better braking, easier to find parts etc. The older style axles get a bad wrap overall imo. Better braking is a solid plus but there are other pros/cons. Pros being the older closed knuckle design is easy to maintain/rebuild. Cons for the old one are low-pinion, harder to find parts, and possibly less strength. My point being, is I would really weigh the advantages or disadvantages and intended purpose before making the commitment.

As far as the pitman arm working, you may need to look at that more. I am not 100% certain the later model steers the same(at the same points/heights). If they do, and the taper on the tie rods are the same(meaning all of it is the same) you are fine. Otherwise changes may need to be made.

On the u-bolt idea- I don't think I would spend that money.
On the brake valve- The valve needs to match the brake system. The original will not work properly/safely if you switch to disc from drum. I can not answer on which valve to use specifically but the original will not go with disc if it is the one for all drum.

Not a lot of help but I am sure others will chime in and possibly flame me on the old axle opinon

 

U bolt flip is easy to do but not really necessary unless you like big rocks or need to reduce drag while flying through a mud pit. LOL. I did it on my 72 CC and it does look cool but that's about it.

Loose the factory prop valve and do a adjustable wildwood....super easy other than a few line mods. Easy to get adjusted.

I have the original D60 steering arm if you need one, however someone here needs to remind me/PO wether he needs to ream the hole or not. I know I did it on the 72 but that has crossover. I cant remember if I reamed the 73 or not. I don't think I did.

WFO parts are nice pieces in my experience.

 

Why not just finish off the whole swap right now and put power brakes and power steering in the truck ? I don't know about the disc brakes with no power, might not work too good ?

 

I should have specified in my original post that I do have power brakes today so there's no concern about that area.

For steering I do have a 78/79 4x4 steering box that will go in after this axle swap.
I also have a hydroboost unit off an 1987-1997 F450 Superduty.

I'm keeping the axle swap and hydroboost / power steering swaps separate to minimize the number of big changes happening at one time and to allow for testing of the various stages of braking improvements.

 

I'll take you up on acquiring the D60 steering arm. PM sent.

Concerning the ubolt flip I see a lot more big rocks than I do mud since I'm in so cal where we typically don't have a lot of rain, this winter being one of those exceptions with all the rain/snow we're getting.

For the wilwood I'd just need a single in/out in the rear brake line right?

 

If you're wanting to run the correct OEM brake valve for a disc/drum setup, you need the brass-bodied Weatherhead valve that's rated for trucks with a GVW of 6900# or greater.

The cast iron Kelsey-Hayes valve is for front disc brake trucks with a GVW of under 6900#.

When bleeding out the front brakes, the pin on the K-H valve is pulled outwards. On the Weatherhead valve, the pin is pushed inwards.

 

In October last year I completely removed the Combination Valve from my F350's braking system, and made up new brake lines accordingly.

Without any other changes done, it felt like I'd just done a brake upgrade !

I must admit that I wasn't totally surprised as the brakes had never felt like they 'bite', even with every other brake component replaced with new parts over time.

So, based on that, I would say yes to eliminating the valve, and yes to fitting a proportioning valve to the rear circuit. (Single line in and out is correct.)

A quality part, such as Wilwood already mentioned, would be my first choice.

But !

Although I think the brake pressure differential warning light setup is crap, I would suggest having a warning light.

I stole ultraranger's modern MC idea whereby it has an aluminium body, transparent reservoir, and provision for a warning light connection.

The fluid level warning light works a charm, and in my opinion, is far superior to the OE warning setup.

If you like the idea, ask ultraranger if he happens to know what modern MC would fit your setup. (Or fits the F450 hydroboost if need be.)

 

i did the wilwood when i did my 75 swap with a 78 kpd60 and works good, make sure you adjust it, i had mine to much rear braking set up at first and (i have d70u rear) when winter came i hit the brakes and did a 180 because of it. turned that puppy way down after that.

 

Based on your experiences it sounds like I should go with an option 5 variation.

Skip1970 do you have pictures and/or a description of where you plumbed in your rear circuit proportioning valve? I heard some put the valve up by the master cylinder, some down low near the front frame rail and others towards the rear axle.

FMJ. I found your thread on the CV replacement with a few pictures. Did you eliminate the (new) CV that you pictured with a "17/08/2016 12:03" date and time stamp in October of last year? If yes, how's your setup look now? I think you're now running 4 wheel disc brakes?

 

mines on the frame rail above behind front tire area so i can adjust it putting my arm in there.

 

I'd forgotten about that thread.

The modern MC I was hinting at is pictured therein.

Yes, the new CV was put in the bin.

When I changed it, it was the only thing I changed, and it was exactly the same lack of performance as the OE one. (I assume it was OE.)

My CV was originally on the left hand side, but seeing as my truck is a right hand drive, I moved the connections to the right side :



The front brake connecting block is this one :

https://www.summitracing.com/int/par...2erl/overview/

A ''Professional'' fitted my Wilwood proportioning (PV) valve 11 years ago to fix the rear lockup issue I was having.

Hah ! It didn't work, and I've never used it. The lockup issue was mechanical, not hydraulic, which I eventually worked out.



The modern Wilwood PV doesn't require adapters (brass parts in above picture) :

https://www.summitracing.com/int/par...0922/overview/

I'm going to leave the PV where it is, and it's easy enough to adjust, but if my MC lines faced the right side instead of the left side, I'd fit this :

https://www.summitracing.com/int/par...3190/overview/

This is cheaper, although without a bracket :

https://www.summitracing.com/int/par...3906/overview/

Yes, I've got 4 disc brakes, but I haven't connected the rear two yet. Tomorrow !!

All lines are 3/16'', and all tube nuts, except for the MC, are 3/8'' - 24 pitch.

I bought this tool so that I could custom the lines how and when I want (like tomorrow ) :

https://www.summitracing.com/int/par...0314/overview/

Yup it's expensive, but I wanted a proper tool, and I can always sell it.

Here's a cheaper alternative for example, but I wouldn't use it :

https://www.summitracing.com/int/sea...%20Tool%20Kits

I used braided hoses from the MC down to the hard lines coz I don't like the look of coiled hard lines.

These brake lines are cheap and real easy to fit :

BHCS: Brake Hoses & Brake Pipes Intro

 

FMJ. Thanks for such an awesome response with pictures and links to part numbers!

I had a couple of tabs open in my browser on the Summitracing site from some researching I was doing yesterday on what I may purchase. I closed all those out because your post and pictures help me to narrow down that I can use these two items:

Front lines - single in, to dual out routing block - https://www.summitracing.com/parts/e...2erl/overview/
It looks like I can orient that any way I want to so I may be able to get away with no changes to my front hard lines.

Rear lines - single in single out proportioning valve - https://www.summitracing.com/parts/w...0922/overview/


I have a Mastercool hydraulic flaring set (p/n 71475) that I'll be able to utilize for any new flaring I need to do.

 

Haha, I like that last picture !

You've just reminded me.

My CV was mounted to the cross member (left side) via a spacing bracket held in by 2 bolts, so I'll assume your setup is the same.

With regard to the front line block, which has a mounting hole in it, you might be able to use the same mounting bracket.

Also, the tube nuts which currently fit to your CV, are probably not 3/8-24, so you might end up making new front hard lines after all.

And another 'also', same applies to the rear line fitting.

Shaping the lines and flaring them wasn't difficult, but it did take a bit of time.

Here's what I used to hold the hard lines against the frame :

https://www.summitracing.com/int/parts/aaf-all18300
(The one holding the rear line in the previous picture is too big, and will get changed tomorrow now that I have the correct size.)

https://www.summitracing.com/int/sea...ibanner=SREPD5
(I can't find the exact part number I used.)

I just took the picture below to try and give an overall perspective, umm, but the picture is a bit crap, but I'm posting it anyway.