Looking for input on doing a front disc brake conversion for a 73 scout ii with dana 30.

Discussion in 'General IH Tech' started by Mr. Schell, Aug 31, 2020.


  1. Mr. Schell

    Mr. Schell Farmall Cub

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    Anyone happy with the kit they bought?
    Do I need to change the master cylinder or brake booster?
    Any other helpful tips or things I need to consider?
    Plan on keeping the drums in the back.
    Thanks, Dale
     
  2. Jeff Jamison

    Jeff Jamison Lives in an IH Dealership

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    Yes you will need a different mastercylinder and proportioning valve.The best thing to do is find a newer scout and pull all of the parts off of it.
     
  3. winchested

    winchested Y-Block King

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    Good excuse for a chevy brake ford hub/ spindle conversion!
     
  4. mallen

    mallen Y-Block King

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    1st question, do the brakes work properly now. Not "are they sort of bad but what do you expect for a 50 year old vehicle" ,but do they work well. They should. If they do not, then something is wrong. They worked just fine when the truck was new. If you upgrade them when the system does not work properly, you risk ending up like all those other poor souls who upgraded the brakes because they were not working right and ended up with it working the same or even worse. At that point your really screwed because now, not only is something broken,but there are very likely to be OTHER things wrong that you caused in your upgrade and you have no way to distinguish between the two caused. Your allways much better off getting things to work 100% right, and only then changing things around. Then when it does not work right,which 99 times out of 100 it won't, you know that this was caused by what you did and you can concentrate on that.
     
  5. Mr. Schell

    Mr. Schell Farmall Cub

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    The current drum brakes actually stop well in my opinion. I just purchased the vehicle in March, so I have not taken them apart to see the condition yet. It has just been suggested by others that front disc is kind of a must have/saftey issue in todays traffic.
     
  6. mallen

    mallen Y-Block King

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    If your brakes work well ,why are disc brakes suddenly an "omg safety" issue. They work just fine and brake fade is not an issue unless your dragging a huge trailer down a massive incline. Even then, it's only an issue if you don't understand your driving something with disc brakes. 4 wheel disc brakes were used into the 90s. I would suggest, that the only reason you NEED disc brakes is if you WANT disc brakes. If it's just about stopping the truck, they are fine.

    Honestly, all the "definitive" sites saying "OMG drum brakes are putting your families safety at risk just to save 1000 dollars upgrading to disc" (yeah, one literally said that) are sites that are selling disc brake upgrades. One of their arguments was some B's about springs getting weaker with age. Which is true enough, but that's why you put a spring kit in with your new shoes. If your worried about safety, put in some new brand name shoes, new springs and new cylinders, replace the rubber lines and the master cylinder and if the hard lines are rusty and old replace those too. It should be around 200 bucks. Measure the inner diameter of the drums to make sure they are in spec. Unless they are scored I don't like to turn them. Old drums can be hard to find so I don't cut metal off them unless I have too. If you get them in tip top shape and maintain them properly they will stop your car for another 50 years.
     
    Last edited: Sep 1, 2020
  7. 72soa

    72soa High Wheeler

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    I am in the camp that drum brakes are not really suitable for todays driving. Back in the day when everyone had drum brakes not one stopped well. So is was kind of an equalizer. Today there is so much traffic and so many morons on the road discs - at least front - make a ton of sense. I have done various conversions using scout II discs or a combination of scout II rotors/hubs and chevy backing plates and calipers. I have done conversions on dana 27 closed knuckle units as well. Scrounging for parts and sweat equity will make the conversion manageable from a cost standpoint. Well worth it.
     
  8. stroker3

    stroker3 Lives in an IH Dealership

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    Agreed there's more traffic and many more morons out there today but there were morons back then too. I never had an issue stopping with drums brakes all around . So I agree with Mallen about swapping out the drums simply based on the assumption that you need to have front disc in today's world. If that's the worry, ABS and airbags should be installed as well. Beyond the understanding of what deep puddles and water along with long down grades and heat can do, I'm afraid that's nothing more than a moron inidicator in itself. Simply pay attention and don't tailgate. Know what you're driving and drive accordingly. My SD has a warning that's it's not a sports car and shouldn't be driven like one. Same sense should be used with a 40 year old car. If someone want's disc's, that's just fine. Calling them dangerous or not good enough in today's world is BS. They can be locked up , or better yet, pumped when needed to stop just fine on slippery roads. In the end, they're only as dangerous as the one behind the wheel. The problem with 'today's' world is everyone thinks driving is just something you do while multi-tasking and we're begining to expect, and even demand, that the car has to do everything for us. A forty year old vehicle simply can't be that.
     
    Last edited: Sep 1, 2020
  9. mallen

    mallen Y-Block King

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    By that logic, if your not driving a Caddilac with sticky tires and abs,your needlessly risking your life.

    The thing is,disc brakes are NOT going to appreciably change your stopping distance under most circumstances. Its simple physics. Consider the following thought experiment. You have two identical trucks,except one has disc brakes and one has drum. Each vehicle will lock it's brakes if you stomp the pedal hard enough. At the point just shy of locking, the brakes produce maximum braking force. Beyond that point it slides instead if rolls.
    Since the same force is applied to each vehicle, they decelerate at the same rate and stop in the same distance. It's not magic.

    New or old, if those brakes are not stopping the vehicle, something's wrong. Fix it. Now, disc brakes ARE better than drum brakes. But not for stopping distance under ordinary circumstances. By ordinary I mean, driving around town, not on massive grades towing massive loads or fording flooded streets or putting it on a race track. And all of those can be done safely, with the exception of a racetrack, by understanding that your brakes have certain weaknesses and being careful. (For the racetrack you need giant disc brakes with high performance pads, but you also need a totally different vehicle than a a scout)

    This meme that gets perpetuated that disc brake vehicles never stopped right is simply incorrect. They did. I had a old 68 volvo that used to stop on a dime. The suspension was terrible and if you took an offramp too fast it had a tendency to go into a flat spin and try to murder you with no warning. (One second it felt fine, then a bit faster and you were flying across the road perpendicular to traffic, facing backwards watching the other cars swerve to avoid hitting you. At least it had three point seatbelts.) Even that was avoidable by not being an idiot. If the car tried to murder you when you push it near that edge around a corner, you just make sure you never ever get near that point. But I never had any complaints about the brakes.

    I'll repeat this again, if your vehicle does not stop right, something's broken. Fix it.

    FYI, other modifications that won't do much, or anything at all, for your stopping distance are power brakes, fancy brake pedals, expensive brake fluids and upgraded brake pads. They all have their places. They may decrease maintenance or increase longevity or work under extreme conditions. So you might want them. In the case of power brakes, it makes it easier to push the pedal and might even hold off surgery on that disintegrating knee joint that you badly damaged 40 years ago playing high school football. But they don't do much to change the force applied to the vehicle just shy of the wheel locking up. And that's what determines your stopping distance.

    There is one thing that WILL change that. Your tires. If you want to reduce your stopping distance, choose a good street tire. Not those tires designed for a muddy pit. They are great for that, but not as good as one that's made for pavement. And definitely not those 25 year old, bald tires that are so oxidized that the rubber is hard and is cracking and coming out in chunks.

    So if your worried about safety, buy a new set of street tires. They will do more for your stopping distance than all the expensive disc brake upgrades on the market.
     
    Last edited: Sep 1, 2020
  10. Darrel

    Darrel Dreams of Cub Cadets

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    What size tires, Dale?
     
  11. Mr. Schell

    Mr. Schell Farmall Cub

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    I was thinking 31s as I am trying to decide between a 2.5 and a 4 inch lift.
     
  12. jeff campbell

    jeff campbell Lives in an IH Dealership

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    Slow down, scouts aren't like todays cars or trucks. They're relics.drum brakes work good if adjusted correctly.
     
  13. Darrel

    Darrel Dreams of Cub Cadets

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    You should be fine then with the drums for light to moderate use. Driving hard, lots of mountains, heavy loads would be a different story. Personally I would always upgrade, but the parts do add up. Wilwood makes a good adjustable valve.
     
  14. mallen

    mallen Y-Block King

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    I bet the loss of handling from a lift , although minimal if done right vastly outweighs any potential safety benefit from disc brakes. In fact, considering the speeds you will be driving ANY scout at, much less one with a 4" lift, brake fade won't be an issue. If your driving it up and down hills at 80mph , braking hard into curves and down steep grades, the brakes are not what's going to kill you. If you drive it reasonably, the brakes won't even be taxed. Driving hard is just not something you are going to be able to do in a scout. And heavy loads, if they are within the rated vehicle weight limits, will be just fine. The engineers selected the components in your vehicle to handle that. They had hills back in those days too. If you overload, it's not a great idea but if you do it, you should be creeping along in the slow lane. If you over load it and hit the mountains at 70mph up and down those grades,with a half ton in the vehicle and another 4 tons of trailer behind you, then your just stupid, and no amount of upgrades can overcome a stupid enough driver.
     
  15. 72soa

    72soa High Wheeler

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    One good off road romp through some standing water/mud will raise havoc with drum brakes. Drum brakes will stop a vehicle but discs are better. Discs are easier to maintain and otherwise work on. I have driven plenty of drum brake scouts - daily drivers. I was young and did not know better. I never hurt myself or killed a bus load of nuns or anything like that. They did stop and I was never scared. Two daily driver scouts were converted to discs. I still have one of the scouts. It made a huge difference. I am an advocate of disc brakes on a scout. All of the modern vehicles have discs. Most have 4 wheel discs. Something there. The conversion on a scout is not that hard or really expensive. Just a little time consuming. Yes you have to pay attention while driving no matter what brakes. But the discs will give you an edge in a moment of inattention. I know we have all had those once or twice. I don't know what the traffic is like where ever you all live but where I live it is hell. A scout on the interstate can be difficult. Yes I still drive mine on the interstate but I do not do it all of the time. Much prefer modern vehicles on those types of roadways.
     
    Ron A and Darrel like this.
  16. Ron A

    Ron A High Wheeler

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    I disagree, here is Sherman Balch, driving his Scout "hard" at the race track. No brakes and using his good friend Rodney Hall to help slow him down.
    Silverbird.jpg
     
  17. Ron A

    Ron A High Wheeler

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    Only other thing not mentioned is the current condition of your Dana 30. If it is in need of much work, you might consider looking for a complete 44 from a donor Scout II and swap the whole thing. Just watch the gear ratios. Been a while but I remember getting new front drums from IH under warranty. The new ones had cooling fins. They stopped just fine until they got wet.
     
  18. mallen

    mallen Y-Block King

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    Well, I'll give you that one.
     
  19. stroker3

    stroker3 Lives in an IH Dealership

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    Not saying disc are not 'better' overall but the claims that drum brakes are not safe today is BS. The entire scout is unsafe under the same way of thinking and comparisons. The drums do reqiure some knowledge about water and heat but disc can heat up and fade as well. One of the first things you should be taught is riding the brake for a 100' feet or so after hitting a deep puddle with drums all around. FWIW disc can have their share of issues as well. Ford had/ still have some issues with calipers freezing up unexpectedly and overheating, repeatedly,. and that causes some braking issues as well. I've had ice build up on them too after a night of plowing. It has become very costly as far as brakes, calipers and rotors go. My GM had issues as well with the front disc grabbing more while the rear drums hardly worked making it very dangerous from day one in any sort of slippery conditions. Front disc would lock up and you'd have no control as the rears pushed you along. Tossing it in neutral with a prayer was the only thing you could do. Lost count of how many times we had very close calls sliding through a stop sign and how many times it was brought back to the dealer. Only brand new vehicle I ever bought and the main reason why I'll never buy another GM product. Not so much the problem, but the fact that several dealers had no clue on how to fix it. All in all and as much as I like disc brakes on the newer vehicles, mainly for the ease of replacement, they're not always perfect either. Most importantly, drum brakes are not any more dangerous in today's world than most things in a 40 year old vehicle.
     
    Last edited: Sep 2, 2020

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