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Tech Support

I have been selling disc brake conversion kits for Mopar vehicles for over 20 years now since the early days before a real internet came about. Out of the hundreds of kits, nearly a thousand so far, I have had a handful of people who were less than pleasant to deal with.


When I first started Rustyhope I set up a phone number for people to call for information, tech support, and ordering. When I started getting calls at all hours of the day and night, seven days a week I decided to set up the web page and offer email tech support only. The main reason was that while most people called at reasonable hours and had reasonable requests some people were simply jerks. The guy who couldn’t or wouldn’t read the directions would call after a few beers and give me an hours worth of grief simply because he was too lazy to read the directions.

This recent exchange shows why I prefer email for tech support.

My comments in Blue, customer’s comments are in Red.

Chris, I’ve just gotten home and have read through all ten of your emails plus the initial four you sent me before ordering your kit. I will try to sort out your questions and help you complete your project.

1. 2:16 pm- Say, I’m just starting this disc brake conversion and I got all my holes drilled and am on step #3. When I put the spacers onto the spindle, the are pretty loose. I don’t know what you mean by “peening” anything, sorry for my ignorance, but I’m wondering how to get them to tighten up, first of all, and second of all, are they supposed to go all the way up onto that flange and up next to the plate part, or do they sit down and away from the flat part? Not very clear Partner. Thanks


It is not uncommon for the spacer to be a little loose on the spindle, I planned it that way. I found over the years that if I made them fit very close to the diameter of the spindle people had problems with them being too tight. This is harder to overcome than being a little loose. I did not want people grinding away on their spindles or the inside of the spacer either. So, I make the spacers a little oversized for 1.25” which is the normal size of the spindle diameter. Peening is striking the spindle with a center punch, repeatedly, preferably in a regular pattern around it’s diameter. This raises small bits of metal that fill the gap between the spindle and the inner surface of the spacer. The spacer is held in place by the pressure of the bearing on its outer face which is a result of the spindle nut being properly tightened. The small amount of play in the spacer is acceptable once the bearings are tightened up against it.


2. 2:56 pm- Well, while waiting to hear back on the bearing spacers, I went ahead and mounted up the brackets and everything bolted up well, except now the arced steering control arm on the drivers side hits the front shock linkage bracket that is on the top of the axle where the spring mounts. Looks like I need to heat it up and bend it a little more maybe? Will that be ok to do to the steel? Lemme know, thanks.

I replied to this one earlier from my I-phone, but yes you can heat and bend the steering arm. However, if you adjust the tie rod ends to account for the thickness of the 3/8” thickness of the caliper bracket the interference may be eliminated. I would not bend anything before carefully adjusting the toe-in and looking to see if everything else is in correct position.


3. 5:51 pm- Steering Arm photo. See my response to #2 above.


4. 6:03 pm- What about the bearing spacers? See my response to #1 above.


5. 6:34- Ok, well, the bearing spacer and the bearing are plumb loose on the spindle. They wabble all around. There’s a good 1/16″ plus of play in it. The spacer appears to fit nothing, not even the new rotors. And I got every part on the list that you gave me and there are no dust covers for the inner bearings at all. What’s supposed to keep dirt & gunk outta that bearing? I’m guessing I can go to a machinist here in town and have him spin me out some new bearing spacers, unless you have a better idea. I’m fairly disappointed in this outfit so far, to be honest. Plus, I didn’t think this was gonna be a week long project.


See my response to #1 above, and #10 below. The spacer does not “fit” the rotor, it sits between the inner bearing and the raised shoulder on the spindle. I replied earlier to the “dust cover” issue from my I-phone, there are part numbers included in the instructions for “grease seals” and according to your email #8 below you figured out you forgot them on the parts counter at NAPA. You certainly can have new spacers made if you want to do that, but unless your spindles are damaged, or undersized the ones included in the kit will work. I am not all surprised that you are disappointed at this point, but I have no control over your ability or skill level. Your email #1 above indicates you just started on the conversion today, this afternoon, but #5 says you’ve been at it a week, which one is correct? I do not have control over how long you take to do a project. I can do this in under three hours, but I’ve done a lot of them, and I am a very capable mechanic.

6. 6:45 pm- Spindle with mounted bracket photo. Text: The inner bearing is way loose on the spindle, and the outer bearing won’t even go on the darn thing past the threads.

Assuming you have the correct inner bearing your spindle may be undersized. If your outer bearing will not fit onto the spindle it may be incorrect as the bearing specified has an id of .750 which is standard for most Chrysler products up through about 1959.


7. 6:46 pm- and I’m sitting here twiddling my thumbs waiting to hear back from ya

I received this email while responding to #6 above and eating dinner with my family and did reply that I would get in touch as soon as I finished work, (and dinner). I am sorry I could not reach you quickly enough.


8. 6:55 pm- I checked on the seals & the napa guy foegot to out them in the box, they’re sitting on the counter over there. I’ll measure the spindle.


See #5 above.


9. 6:55 pm- It’s a 36 plymouth 2 door sedan

I asked you to confirm what year and make your vehicle was because I get a lot of emails from people who assume I know everything about their project. Knowing the year/make helps me to understand what your problems might be and how to solve them.


10. 7:08 pm- Spindle is exactly 1.193 inches on the fat end and exactly .751 on the skinny end


This appears to be the answer to your problems. Your spindle is either worn undersize, or your car has a spindle that is too small to use my kit. When you contacted me I referred you to my web page which has pictures of the two spindles my kits will fit. It also has information that tells you the kits, both for cars and trucks are designed to fit spindles with a 1.25 or 1.375 spindle OD where the inner bearing fits, and a .750 OD where the outer bearing fits.

11. 8:18 pm- OK, I went and spent an hour or so over at napa and found a different inner bearing with the correct ID and similar enough of an OD to make work, the only thing is that it’s just a tad bit thicker than the one you told me to get the first time around and when I put it all up there on the spindle, with the spacer you supplied, there’s not enough threads left on the spindle for the washer and castle nut. This spacer is the common denominator in a lot of the troubles so far, I’m wondering if you have a different one, or can build me a different one? How far should the rotor be from the bracket you built when everything’s up there?


The kit is designed to work with the parts listed in the instructions. There is nothing wrong with the spacer, it works with the bearings and rotor listed in the instructions. The fact that it doesn’t work with the bearing you found doesn’t mean there is anything wrong with it. You cannot arbitrarily change a part and expect everything else to fit and work properly. Your problem appears to be the diameter of your spindle, not the thickness of the spacer. I do not recommend you changing parts in the kit.


I understand that you are frustrated with the process so far, but other than your spindle diameter being too small there is no problem with the kit fitting or working as designed. Your best bet would be to find a way to shim up your spindle diameter to 1.250 with a bushing. The same bushing could be used to shim the spindle up where the spacer fits. You could also change to spindles with the larger diameter, but that could be costly and time consuming. I can make spacers for you that would fit your spindle diameter and maintain the proper spacing for the rotor and caliper. You would still have to resolve the fit of the bearing and other than a bushing I have no suggestion. You simply cannot randomly change parts and expect to have a safe working brake system, it is really important that you do not do that.

The problem you have is your spindle, not my kit. However, if you want you can ship your spindles, spacers, and bearings to me. I am confident I can make them work together as intended and will do that for you at no cost other than your shipping to me. My shipping address is 6405 Old Kissimmee rd, Davenport, FL 33896. I stand behind my kits and my workmanship. I’ve done this for over 40 years now and will do whatever I can to help someone with their project, but I will not take abuse over someone else’s mistake or misunderstanding of the process. If you want my help, let me know.

12.10:54- I appreciate you taking the time to finally respond to all my questions, and I understand you don’t recommend or stand behind it, but I changed out the inner bearing altogether with a different one and am not using your spacers at all. I have mocked everything up with your setup and by the time the spacers are in there and the inner and outter bearings are all in place, there’s not enough threads left on the spindle to grab with the nut, let alone try and put the cotter pin through it. If it take the spacer out, go with MY inner bearings and dust seal, but stick with the outer bearing in your parts list, and mock everything up, voila! Just enough threads left to put the castle nut on it and a cotter pin! It appears to be perfect. By the time everythings snugged up and on there, I need to have right at 11/16″ of clearance between the rotor and the bracket, in order for the caliper to be in the right spot, and with my setup, it’s 11/16″ on the money. I’m disappointed in a lot of things here, but understand variances in spindle sizes and so on are beyond your control. How many of these kits have you sold so far? I have a hard time believing nobody’s had similar problems, regardless of their mechanical skill level. I’m no ASE certified dude, but I’m not a cafe cowboy either, I can figure stuff out typically without many problems and a car built in 1936 is definitely not overly engineered in the first place.

If you read the instructions for the kit, and look at the pictures you will see that the castle nut is indeed on the very outer end of the threaded portion of the spindle. I planned it that way. The spacing of the bearings and the thickness of the rotor use up all of the available space between the inner face of the spindle and the outer tip of the spindle. This is the way the kit was designed to work with the Mopar spindle. I have sold hundreds of these kits over a twenty year period. How many cars or trucks have you converted to disc brakes in the last twenty years? I am sorry you are disappointed, but you failed to read the information on my web page that would have alerted you to the problem that you are now having. Your spindle diameter is too small. You cannot randomly change the inner bearing and have the kit work as designed.

13.11:44 pm- Scratch my last email. When I snugged everything up, my 11/16″ shrunk down to 9/16″ and the rotor started rubbin on the bottom of the spindle plate and the rotor sits too close to the bracket to allow for the inner brake pad. So I tore it all apart AGAIN, and put it together your way. It all goes together nicely, but that daggone inner bearing is too loose on the spindle. It wiggles on there even after everything’s snugged up. Other than shimming the bearing and spacer, you don’t know any solutions? This is a joke. I’ve now FUBAR’d my whole front end and can’t even put it back together with the original drums. I’m pissed, and I’m quittin’ for the day. It’ll bug me all night long and I’m afraid I still won’t have a solution figured out by tomorrow and have other work to do in the morning, so I guess I’ll try and sit and look at it some more tomorrow afternoon.


I have offered you at least two workable solutions based on my experience. If you do not take my advice you cannot benefit from my experience. I cannot help you if you want to modify the kit or install it incorrectly.

Hundreds of people have done this conversion correctly and their cars and trucks work properly and stop safely.


14.8-27-10- 8:01 am Well, I ain’t sending you my spindles yet, so it looks like my only other option is going to be to shim the inner bearing so it’s snug on the spindle……correct? Is copper ok to make a bushing with? I’m thinking I can take some 1″ copper tubing and cut a length of about 1/2″ and then cut the piece so it can expand to the exact size when going over the spindle. If the thickness of the wall of the copper pipe is too thick and the bearing is too tight, I should be able to sand it down a little and get the inner bearing to be snug on the spindle. Then I believe all my problems will be alleviated, as everything else works good I believe.


And if ya think about it, anybody else besides me putting this thing on my car would have the EXACT same problem, right??!!? Maybe quit pointing your finger at me, the only way I could’ve known your bearing would be to big was to take my front end apart and measure the diameter of the spindle. That’s stupid. You’ve sold 400 of these kits and nobody else has had a spindle as small as mine? Come on. I guess it’s your story, tell it how ya want to! My ’36 is an 11,000 mile barn-find, and besides some dry grease on things, the spindle itself is almost 100% UN-worn. No grooves or mars or galling is on the spindle whatsoever, you can still see the lines made by the lathe when it was spun. Your instructions are fairly clear, not great, but descent, and you forgot to mention that I’d have to take the steering arm OFF of each spindle again, in order to get the bottom bolt caliper bolt in the hole!! I’m about $600 into this conversion so far, still don’t have disc brakes, and I think I could get a whole new front axle already with disc brakes for about twice that. If I thought I could get all my money back from this stupid conversion, I’d definitely just go and buy a GOOD setup and be done with it!


It’s clear to me that you did not read my web page as I asked you to do and confirm the size of your spindles. Checking your spindle size before committing to a major brake conversion is not stupid, it’s prudent (look it up). Your 1.193” spindle is the first one I have ever seen in that diameter and I offered to fix it for you, but apparently you managed to cobble something together you are satisfied with, your choice. I’d say the kit worked pretty well in spite of your lack of planning and ability.


15. 7:34pm- I finally got the rotors and calipers mounted up correctly by shimming the spacer and inner bearing with some 1/32″ starter shims. Works fine. Now I’m trying to put on the brake lines not so well. The ones you said to get take a 3/16″ fitting, and the ones on my car are 1/4″. Napa doesn’t have a bushing that we could find to work, so I’ll have to get some brake lines made or something. Bottom line, your kit sucks, and your service sucks almost as bad, and I won’t have a lick of trouble telling people about it. I would recommend you not quit your day job just yet. Thanks for the headaches and good riddance.


Mopar cars and trucks have a number of different sized brake lines over the years depending on the vehicle year, make, and model. The brake hoses were chosen to fit the rotor with the assumption being that whatever size brake line the vehicle had would be adapted to the brake hose. The easiest way to do this is with a brass block. I believe the one you need for your car is Napa part # 7828 at $3.64 each at my local store.

Bottom line, I know nothing about you except what I can guess from the 20 or so emails you’ve sent me over the past two days. I’ve answered every question and email you sent me and offered to solve your problems for no charge. I’ve accepted abuse and insults from you when they were not necessary or helpful to solving your problems. So go ahead and say your piece to anyone who will listen anywhere you can get an audience. Anyone who reads through this exchange will see pretty quickly what the problem was. People know me and my work and that I stand behind it, so I’m not worried. Who you are comes through pretty clearly in your emails to me and ignorance is always ugly. After everything is said and done the problem was you didn’t read the instructions, you didn’t follow them, and you didn’t accept the help I offered you. I hope that every time you drive your car and it stops safely, in spite of you, you will think of me. Best of luck to you.


Rusty Hope tech support is available by email at


Please include the year/make/model info for your vehicle when you contact RustyHope with any questions and when you place your order.


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