1994 Dodge Caravan Drivers Side Brake Locks Up

Thank you for providing lots of good details. First eliminate the possibility of contaminated brake fluid. Inspect the rubber seals under the reservoir caps. If they are blown up and mushy, there is petroleum product in the fluid. That's a nasty repair.

Next, open the bleeder screw of the stuck caliper. You'll see a little spurt of fluid and the wheel will turn freely. You should also notice the brake pedal is higher and harder than normal. Grab a large channel lock pliers and look at the metal bracket crimped around the center of the rubber brake hose. Rust buildup inside that crimp has constricted the hose. Fluid can be forced past the crimp by the high pedal pressure, but it can't release back to the reservoir. Use the pliers to open the crimp just a little. If the hose is frayed anyplace, it should be replaced, but if it's in good shape, just fix the bracket.

caradiodoc

[quote:1964d0f4cf="Notzorro"]Brakes problem
1994 Dodge Caravan 6 cyl Front Wheel Drive Automatic 145000 miles

Driving for a short time, applying brakes normally.
The front brake locks and stays locked up.
I replaced the caliper and rotor.
Problem returned almost right away.
Only the driver side brake does this.
Sure does eat up the pads fast.
Rear drums are in excellent shape Shoes, drums, hardware etc.
No antilock brakes on this van.
Was on the road and there was enough heat generated to melt part of the plastic hub cap.

Suggestions?[/quote:1964d0f4cf]

Did you happen to notice if the brakes pull to the passenger's side when you first apply them (i.e., before things start locking up)?

Sounds like a dirty/clogged brake line on the driver's side, most likely in the flexible hose. This is especially likely if the driver's side brake releases after the vehicle has been sitting idle for a while (e.g., overnight).

I know it sounds weird, but I actually had this happen to me with the rear flex hose on my 1970 Dodge Coronet 440. The nature of the clog made it act like a one-way valve so it wouldn't let the rear brakes release after I applied them.

No, it's not weird. Well, ok, but I'll tell you what's more weird:

I have an '89 Grand Voyager that's just sitting for the day, (that will never come), that my '88 Grand Caravan dies. Drove the '89 after it had been sitting for a year, and right away it had a real high, hard pedal, and the dragging brakes. Had my students pour over it for hours without my intervention. Gives them a real sense of accomplishment, (I didn't know what the problem was). They noticed right away that the right caliper released when they opened the bleeder screw. Eventually, that's how we found the rusted bracket I mentioned in my previous post. Peeled the crimp open just a little; no more problem.

We read about hoses becoming a check valve all the time, but never actually see one. In 16 years as a mechanic, nine at a really nice family-owned Chrysler dealership, specializing in suspension & alignment, and brakes, I never found a constricted hose once. Here's the weird part. Two weeks after finding my hose, a welding teacher came in telling me about one of her students having a brake problem he couldn't figure out. It was a Neon with the same style bracket and had the same problem. Two rusted brackets in two weeks. Two rusted brackets in 25 years! Now that's the first thing I suspect, especially living up here in Wisconsin, the road salt capital of the world!

One note though. This problem will not necessarily cause a pull. Logic would dictate otherwise if your experience is with older rear wheel drive cars, but the scrub radius, (an alignment angle) is modified on front wheel drive cars to cause a wheel to steer toward the center of the car when braking. That is done to prevent a severe brake pull when one half of the split-diagonal hydraulic system springs a leak. I would never admit that I've been driving my '88 almost every day for the last three months with an internally-leaking master cylinder. Only the right front and left rear brakes are working, and there is no hint of a pull. Not even a telltale twitch in the steering wheel. It even stops fairly well. The only symptom is the low pedal and the warning light telling me how stupid I am to keep driving.

caradiodoc

Based on my experience, I would have looked at the flex hose right away, and probably would have just replaced it. When I was working on that '70 Coronet, the right-front flex hose actually burst while we were bleeding the system. I ended up replacing all of the flex hoses on principle. They're the weakest point in the system and if any of them show signs of distress, I feel safer replacing all of them (ideally, with braided stainless-steel-jacketed hoses).

Not only that, the idiot who put the thing on didn't install it correctly. He had clipped the the hose into the bracket *before* tightening the fitting on the wheel cylinder so the hose was actually twisted into a full loop between the bracket and the cylinder -- no wonder the thing let go!

I might never have caught on to the rusted bracket constricting the hose. I'm in Florida, so rust is not a problem. My '98 is amazingly free of rust underneath.

The only rust problem I've had was with the water line to the rear heater core, where the rubber line connects to the (expensive!) stainless-steel line coming from the engine. I discovered it when I had stopped at a tire shop to check prices about a month after I had bought the vehicle (for $1,800, from a dealer, no less!). I'm talking to the clerk, turn around to point out my vehicle in the parking lot, and there it sat with water and steam pouring out from underneath the middle of the vehicle.

Fortunately, I was able to effect a repair by cutting off the rusted end with a tubing cutter and fitting a slightly longer piece of hose.

Now, I need to find a replacement for the spare tire retention mechanism. Discovered that my left rear was low this morning because it had picked up a screw last night, near the edge of the tire where a "plug" repair would be ill-advised. The shop offered to put the spare on for me, but the stupid cable jammed on its spool up inside so that now it won't move either way no matter how much (or in which direction) you crank the nylon nut in the floor. They had to cut a hunk off of one side of the nylon tee off to get the spare out.

It never rains, it pours!

Funny you should mention the rear heater hose. I assume you're talking about a minivan. We had a huge problem up here in cold weather. The o-ring inside the plastic quick connect fitting would shrink up and leak. Would have a green puddle by the right rear tire. The only repair approved by Chrysler for warranty repairs was to use a pair of new superceded hoses that each had TWO rubber o-rings that would shrink and leak. For vehicles out of warranty, we just threw them away and ran bulk rubber heater hose with regular clamps. That made a permanent repair.

I had a '70 Coronet once. Took the oil pan off, unbolted the busted connecting rod, put a mirror on the ground, and watched it run on seven cylinders! Body was perfect. Sorry now I hauled it to the junk yard. :(


So, notzorro. Now that we're totally off the subject, have you made progress?

caradiodoc

[quote:f67a4e703a="caradiodoc"]Funny you should mention the rear heater hose. I assume you're talking about a minivan. We had a huge problem up here in cold weather. The o-ring inside the plastic quick connect fitting would shrink up and leak. Would have a green puddle by the right rear tire. The only repair approved by Chrysler for warranty repairs was to use a pair of new superceded hoses that each had TWO rubber o-rings that would shrink and leak. For vehicles out of warranty, we just threw them away and ran bulk rubber heater hose with regular clamps. That made a permanent repair.[/quote:f67a4e703a]

Yeah, I hear you. I love the vehicle, but boy, Chrysler sure made some really dumb decisions in some elements of its design. When I fixed the heater hose, I also replaced all of those el-cheapo spring clamps with proper screw clamps.

Now, I need to replace the radiator because it has a hariline crack about an inch long at the top of the passenger's side tank. Fortunately, it only opens up enough to "weep" a little bit, and only then when it gets hot enough for the fan to turn on. As long as I keep moving, it doesn't get hot enough to leak at all.

[quote:f67a4e703a="caradiodoc"]I had a '70 Coronet once. Took the oil pan off, unbolted the busted connecting rod, put a mirror on the ground, and watched it run on seven cylinders! Body was perfect. Sorry now I hauled it to the junk yard. :([/quote:f67a4e703a]

Oh, I really miss my Coronet. Only paid $500 for it, and the damn thing ran like a top, even after I nearly destroyed the valve train by flushing the crankcase. I should have flushed it 2 or 3 times instead of just once. Of course, it waited until I was out in the middle of nowhere before it sucked up enough of the loosened sludge to completely clog the oil filter and oil pickup. Don't those 318 motors sound just *lovely* when there's no oil supply to the lifters?? :-)

Eventually, the county towed it away because at the time, I couldn't afford to keep a tag on it and had no place to store it.