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Discussion Starter #1
Does anyone know if I can swap out the drum brakes on my 2005 Caravan for the disc brakes on a 2004 Grand Caravan? I've been looking around and I see a lot of posts about swapping and the majority of responses are "don't do it, drum brakes are great on the rear...". In my experience they are not. I had my drums serviced professionally less than two years ago and now they are done again. My wife has the 2004 Grand Caravan and no issues with the rear disc brakes. I am not concerned about stopping power or effectiveness of the parking brake. I do not drive aggressively or park on a hill. Her car is beyond repair (motor and other stuff) and I'd like to scavenge the disc brakes if they will fit. If it matters, the 2005 has 3.3L and the 2004 3.8L. Thanks.
 

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Welcome to Allpar. By "done", do you mean that the shoes have already worn out?
Look for dragging shoes caused by parking brake, wheel cylinder or hardware issues.
Drum brakes should be fairly trouble-free. A lot of work and used parts are involved in change-over.
The rear shoes in my wife's 2002 Caravan lasted 100K miles. There was a TSB for rear brake water-ingestion and subsequent noise.
 

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Discussion Starter #3
IC, done as in constant noise when driving and grinding when braking. My front rotors are warped and grooved so they are getting replaced too. Figured while I am fixing the front and I have a potential donor for the back I'd see if they were compatible. Thanks.
 

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KOG
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It can be done, but you'll be swapping the master cylinder and the ABS module. Might be more to tackle than you want by the time you sort out the wiring.
 
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Is the grinding noise because of excessive rust build up? Does the noise subside after the first few stops of the day?
This is kind of what the TSB addressed.
The high-metallic content of the OEM rear shoes actually got a layer of rust on them from sitting overnight in damp conditions. Going with semi-organic or ceramic shoe linings can help prevent this AM brake noise.
 

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Discussion Starter #6
No the grinding noise persists. I also hear it in reverse. As the brakes were done, I'm not sure what kind of pads are on there. But it wasn't all the time, just slowly building up recently, so I assume it is because they are worn and likely cutting into the drums now. They're just such a pain to service, whereas I can do a set of pads in 15 minutes.

KOG, I hadn't though about all the ABS and wiring stuff. you might be right. The idea came because way back when I was a wee little lad I had a 69 Mustang and apparently could swap out all four drums with I believe newer model Lincoln disc set or something like that. Easier back then, to be sure.
 

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I would begin with a visual inspection.
Rusty drums can grind like 'metal-to-metal' and the shoes themselves may still have plenty of lining left on them.
If the rear wheel cylinders are sticky, then the rear shoes won't be 'self-cleaning' themselves against the drum every time you stop. This will also make the front brakes work harder to stop the vehicle and you will wear front pads and warp rotors faster than you should, because the rears aren't doing their fair share of the braking.
 

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Agree with a visual inspection. The thing is, you mentioned the front rotors were wasted also, so there is a driving, braking and weather condition issue, not brake drums on the rear issue, as in overhard braking, deep puddles, really helps to slow sooner and use the brake a little lighter. KOG is right about the amount of work and the other components issue for disc on the back is also an issue, (I can't say for sure whether or not a PCM or BCM computer would require a flash to counter the different type brakes, but I wouldn't discount that), and disc do wear a little faster on the rears for some reason (at least they do on my PT Cruiser compared to the drum rears on my PT Cruiser). A lot more work than it is worth, and yes, ceramic is the way to go for disc or drum brakes these days, along with, since you are replacing the rotors, don't get the cheapest ones you can purchase, take it up one level of expense for higher quality.
 

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The Neon SCCA racers were swapping their rear disc brakes for rear drum brakes because there was no difference in performance and the rear drums were lighter than the rear discs. But, having driven both, I do prefer 4 wheel disc to front disc/rear drum, simply because there is better pedal feel, lower maintenance and the rear disc don't require adjusting all the time to keep perfectly performing brakes.

The often adjustments is subjective, for proficient working rear drum brakes you just have to read the Owners manual about how to activate the self-adjusters and do the simple procedure every once in a while, if its even necessary. If you want sports car like responsive brake performance, then you would need to do it more often, which for rear discs you never have to do it.

Probably your best approach would be to get the OEM parts catalogue for both year mini-vans and compare the part numbers between the with the options, obviously where the part numbers differ is the equipment you have to swap over.

In most cases (cause I don't the specifics for an '04 and '05 mini-van) since you have a donor car, you have to swap over everything from the knuckle on the axle over. If its rear independents suspension, you often have to swap over the entire knuckle.

It is possible they have a whole different axle for rear drums and rear discs, the parts catalogue will tell you that. Many cars with rear independent suspension have an entirely different knuckle for each brake type.

Then you get into the hydraulics and ABS.

Hydraulics, the pressures rear drums require are different than rear discs, so at the very least you need to swap proportioning valves. Because of the different required pressures, which change the overall required pressure, they may have different Master Cylinders and perhaps even different brake boosters. Since rear drums require a lot less pressure per stopping power, keeping the original Master Cylinder and Power Booster (if they are different) might result in needing much higher pedal pressure per stopping power than typical cars.

You also have to hope the lines are the same between drum and disc, its possible they are NOT and you have to swap over lines as well, which more than 10 year old lines are likely to break trying to disassemble them.

Then you get into the ABS system, and perhaps a few other systems tied into the ABS, like traction control, Stability control, roll mitigation, etc.... Its likely they use the different sensors for rear and drums and discs, but they plug into the same socket and work the same with the system. But you never know, perhaps there is a whole other ABS system for the different brake configurations, the parts catalogue can tell you that. The sensors are likely electrically the same, but physically different since they have to mount and read the tone teeth differently.

And finally, even if the part numbers for the ABS and electronic modules are the same, the swap may require some sort of electronic reconfiguring of the ABS and associated systems to make it understand it has rear discs now and NOT rear drums that might require different profiles/algorithms/programs/parameters. This would require the dealer's electronics tools and them doing some interaction with FCA Hq to modify the database at FCA Hq with the vehicles build specifications, so the electronic tool can get past the idiot proofing to allow the tech to reconfigure the electronics to work with the modification. And judging from what I've seen from a lot of Dealership service departments, that is going to be a huge hassle, you'll have to shop dealerships to find one with a quality service department that actually listen to the customer, communicate between the service writers and technicians, think outside the box and go the extra mile for the customer.

I've seen many service departments (of all brands) that are simple money mills, get the vehicle in and out the door and get the check for the inflated charges. They don't care if they did the job right or NOT. I simply installing a official Mopar Accessory hands free phone Bluetooth kit myself, that required the dealer to enable the module, I go to the dealership and after waiting in the waiting room for an hour and a half, the tech came in to find me cause he had no idea what I wanted done to the vehicle, nor how to do it. I had to re-explain everything I clearly explained to the service writer, then go get the service writer to get the instruction that came with the Accessory that I gave the service writer, and then give them to the tech that explained exactly what he needed to do and the exact sales code he needed to input into the system to update the FCA database on the vehicle configuration. I look at the Service Writer and asked, what exactly is your job again?
 

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KOG
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You're not dealing with independent suspension here and the axle is the same. But it might be better to swap the entire axle to avoid needing to realign the spindles. There are no proportioning valves to consider with the discs because the ABS takes care of that. You'd have to remove the existing proportioning valve on the left rear spring. Every hard brake line (steel) will have to be replaced and a couple of them will require removing the fuel tank. The right front line requires either removing the engine or replacing the fitting on the input end. It would be cheaper to buy a different car. Or to swap the engine and transmission into the 04.

I haven't done this on the year model you've got, but I have removed ABS from three 91-92 models (they simple will not stop with the early model Bendix stuff, later ones work fine.) I also prefer disc brakes on the rear, but this swap is way beyond making any economic sense.
 
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I haven't done this on the year model you've got, but I have removed ABS from three 91-92 models (they simple will not stop with the early model Bendix stuff, later ones work fine.) I also prefer disc brakes on the rear, but this swap is way beyond making any economic sense.
I think the posts before ours was trying to say the same thing, for 1/10th the money, time and effort he could just overhaul the rear drum brakes and get them working in tip top shape and that should give him most of the results he's after.
 

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Oh, I "think" in some states, splicing brake lines is illegal, you will NOT pass a safety inspection. Other states not so, or at least they don't look for it during the safety inspection.

I often wondered about the couples model year mini-vans that one brake line can NOT be removed and replaced with the engine in the vehicle? If that line ever needed to be replaced, and you were in a state that does NOT allow the splicing of brake lines, how do you repair it?

Can plain hard line stock tube be thread through the locations behind the engine, and bent and to shape as it threaded through, then put the fittings on the ends, and double flare the end with a flare tool? I can't believe anyone has pulled an engine just to replace a brake line.
 

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My experience with drum brakes is often the self adjusters seize up and then you get more and more clearance between the brake linings and drum with the resulting low pedal and mushy feel. Every few years it makes sense to remove the drums and make sure the adjusters are not seized up. If the self adjusting function is not working as well as you'd like it is usually possible to adjust them manually.
Even though disc brakes are easier to work on, I would not change out rear drum brakes on an older vehicle, I'd just keep up on the maintenance. Get the special tools for removing the brake springs (wear eye protection here!) and the retainer 'buttons' because those tools make it much easier than using a vice grips to remove springs as we did back in the old days.

On my boat trailer I have stuck with surge activated drum brakes even though everyone thinks disc brakes are far better. While they are on vehicles, on a surge system you will have less drag with drum brakes because of the very strong return springs. Disc brakes are more prone to drag and overheating, esp if a little bit of salt crystals gets lodged around the piston seal....I figured out how to make my drum brake wheel cylinders water proof and they don't seize. I use OMC/Evinrude triple guard grease to lube the manual adjuster threads and this works great.
 
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New Shoes and turning the drums, or new Drums (its often just a few dollars more than having them turned) and a hardware kits (all the small parts in the drum) are pretty cheap also, would go a long way to make the rear drums like new again. At 10 years or more of age, your mini-van probably could use the hardware kits, at the very least the self-adjusters often break and almost always seize up at that age, like LouJC was saying.

Since the ex drove the mini-van and couldn't possibly fathom how self adjusters worked, once a month I would take the mini-van and back it up and go forward hitting the brake moderately hard to activate the self-adjusters and adjust the brakes, to keep the pedal height high and the pedal feeling firm.
 
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