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Drum\ to Disc Brake retrofit on 1970's Ford truck?

I’ve never been happy with the braking performance of my 1970’s Ford 4x4 truck. Drums all around. No PB booster either. Not good enough for a fairly heavy truck in my opinion. There is a power brake booster kit available in the aftermarket, but when I looked at the catalog, there is also a drum to disc retrofit kit available too. That seems like it is a better solution, to put disc brakes on front and say goodbye to the drums. Has anyone had experience retrofitting from front drum brakes to front disc brakes using an aftermarket retrofit kit? What do you think?

If the drum brakes are operating properly they are more than adequate for normal operation. What problems are you having?

Drum to disc is a common conversion for resto-rods, sure it’d be good for your truck too. Discs are better than drums, especially when everybody else has discs.

I’ve converted drum-to-power disc brakes on many older vehicles. However, this is only done if a big powerplant is installed in the said older vehicle. Because if you want to go fast! You have to stop fast!

If you just drive the truck as a sane person, the drum brakes will work just fine.


I think your real problem is having a heavy truck without power brakes. If you convert to discs without a power booster I don;t think you will be happy.
Hot Rod magazine has shown many drum to disc conversions. The cheapest way is usually to get the spindles, wheels, master cylinder, booster, proportioning valve. hoses and fixtures from thr first similar model that used front discs.

Add the power brake booster first, and see how much it affects your braking. Disc brakes aren’t more powerful than drum brakes.

Disc have the advantage of not fading due to heat. Are you towing, or do you carry a lot of heavy loads in a hilly area? If not, then this advantage of disc brakes is mute.

The other advantage of disc is they are not affected as much if they get wet. Do you drive though a lot of deep puddles? Most PU’s have enough ground clearance so drum brakes don’t get very wet and aren’t affected to much by moisture.

The problem I’m trying to solve is that quite a bit of force is required on the pedal, and the amount of force needed makes it harder to modulate and control the braking. Even as I’m approaching a stop sign a slow speed, it is more difficult than I’d like to come up dead stopped at the line, I sometimes end up a little short or a little past unless I make a quick correction of pedal force right at the end of the stop, and especially this happens if at a red light where I’m going faster, and the light turns red and I have to stop quickly. This, combined with a little drifting – right/left pulling which adds to the control problem. Ok, from the comments above, it looks like the best thing to do – at least the first thing to do-- is insert the power booster. Thanks to all for good advice.

Heavy weight is the same as high speed as far as brakes are concerned, so I would be looking up disc conversions. Assuming you’re keeping the truck-any thought to trading for a newer one?

By the time you are done with this you will have spent more money than the truck is worth…It’s not as easy as it sounds to do it right…

Does this truck have over-sized tires on it? They’ll certainly affect how the brakes perform.

Sounds like a lot of work and expense to me for the benefit gained; especially on a 4WD model.

My vote would be to go with a power brake booster and call it good.

The parts for the power booster cost about $350. For the disc conversion, about $750. Yes, I expect a disc conversion is a lot of work too. The power booster is specificially for this make/model/year and designed to fit without any body mods. So I expect it is a relativey easy install. The power booster appears to be the way to go. If that still doesn’t meet my needs, then I can do the disc retrofit if I’m so inclined. Even it is costs $1250 for all the parts, and a lot of labor, I’d rather keep the old gal than send her to the crusher. It’s a sentimental thing. Plus I avoid new truck payments.

I learned to drive in a 1969 Dodge Dart with all drum brakes and no power assist. When I complained to my father about the brakes, he demonstrated that they were good enough to lock the wheels, which showed they were safe enough, you just had to push harder than you would with power brakes. Are you not able to lock the brakes on your truck? If you can, you can achieve maximum braking without locking the brakes, it just takes practice.

If installing the power brake booster makes you feel safer, do it, but I agree with ok4450 that this should be enough.

Another way to compensate is to drive slower, which shouldn’t be difficult on a 30 year old truck. Seriously, if you are out-driving your braking capacity, the problem might not be the brakes.

Sorry, not buying it. My drum cars stopped much more poorly than the discs that came later. When everyone’s using drums that’s not as important as now, when everybody else has good brakes. Being able to lock up the brakes (and lose control) is not an indicator of good brakes.

Sure, try a booster, see how it works

I’m not suggesting locking the brakes is the best way to stop. I’m saying that if you can lock the brakes, you can also get your best stopping distance by applying them to the point just before they lock. It just takes some practice. The fact that they are capable of locking indicates they are more than adequate to stop the car.

If drum brakes are so inherently bad, we need to redesign every commercial truck on the road, because they all use them.

The problem with drums on many cars is not the first stop, it’s that they quickly can fade. Can you make ones big enough to work? Sure, but that’s not what ended up on most cars. That’s why you can’t buy them today, disc brakes are much more effective for the price. And I’m guessing that’s one reason commercial trucks stuck with drums, spend enough, make them big enough, they’ll work.

One of the drawbacks for drum brakes was the self-servo effect that could inadvertently lock up a brake. Properly maintained drum systems were more than adequate but disc brakes obviously were a needed upgrade for high speed operation and driving through high water. If the expense is not an issue and the parts to make the retro-fit correctly are available it will be an improvement. But for me, I would just drive slower and enjoy the scenery.

Whitey, I have a Class B air brake license.
I repair those commercial trucks and I drive them, also
And they have had ABS for some time now, in addition to those drum brakes.
So that tells me that drum brakes by themselves are no longer the top of the heap.