How do I get the most out of my stock brakes?

I know I'm probably rehashing an old subject but search kind of let me down.

I've got a 99 Cherokee with brakes that I feel are even worse than stock. Very little stopping power and a pretty profound pull to the left. Granted, my Jeep is no longer stock - 4" lift and 32's.

My plan is to resurface my front rotors (no slotted or cross drilled), bleed the brakes, and get new pads. I figure pads are the only aspect of this that will provide any improvement. So I want to know what kind of pads you are running and if they offered any type of improvement.

EBC? Auto parts store cheapys?

Or are there any other upgrade I could make to improve braking?

Thanks!

probably ought to replace the calipers if they are at all suspect... the pistons can get corroded and seize or drag

replace all fluids will improve braking response

lubricate the caliper bolts and bushings with Permatex 24110 grease will eliminate the "grab" feeling

check to make sure the rear drums are engaging... my rear wheels would spin freely until I fixed the adjusters

Oddly enough, my stock brakes on my '98 only lasted about 42k miles before the wear indicator started screeching on the rotors. The rotors were still good back then, so I just replaced the pads, which I bought at a Car Quest auto parts store...

Fast foward to today with 32's and with 146k miles, and I'm still on the same pads and rotors with lots of material still left. The rears got swapped out when I installed a D44 at about 120k miles, but the pads on my 8.25 had seen better days by then.

Stopping power and pedal action is still as is was at 42k when I replaced them. I'll probably go with the same brand pads next time, since these have lasted so long. I'm truly amazed with them....

1. Make sure the rear brakes are adjusted, the auto adjusters freeze up and there goes a big chunk of your braking power.

2. Pulling to the right could be an indication that the left caliper isn't doing its job.

3. ehall has given you good advice. Brake fluid is hygroscopic--it draws air from the surrounding atmosphere. Water reduces the effectiveness of the brake fluid--a lot! Should be flushed out with new fluid every two years.

4. Is your brake booster working? Engine off, pump the pedal three or four times and then hold pressure. Start the engine--the pedal should drop about 1" and then hold firm.

Thanks for the input! So your're talking about the adjuster inside of the rear brake drum correct? IF they are frozen do they need to be replaced, hit with WD40 or???

I am now thinking that the rears might not be working because there was one time out on the trail that I had the brakes pushed the floor and one of my rear tires was still spinning. Probably should have realized that then. :doh:

I will also check the booster. And is there any obvious way to tell if one of my calipers is bad? And would you suggest replacing with an OEM caliper or just like an auto parts store brand?

The adjusters don't usually get frozen, instead the mechanism gets sloppy and stops working. Basically the rear shoes are supposed to be dialed into position with the parking brake, and then the adjuster mech keeps the shoes in position by periodically spreading them apart a little bit (to accommodate for friction wear). The top of the shoes are fixed, and the bottom is spread apart with a ratcheting screw. The ratchet screw mechanism is kind of convoluted and can develop a bunch of problems--basically it uses a spring-loaded cable attached to an armature that bumps the gearing on the adjuster screw; the spring can get weak, the cable can get stretched or dislocated, the armature can get worn or loose, the gearing on the screw can get worn, or the screw can stuck, among others. Also, the way the adjuster is setup it only engages when the you come to a stop in reverse so if you don't do some reverse stops during the day it won't engage.

Simple test is lift up each rear wheel and give it a spin, if you don't hear the brakes dragging then the adjusters aren't dialed in. What you need to do is make sure that the shoes have meat, that the main springs are all strong and working. Clean and lubricate the adjuster screw, and make sure the lever engages and that the cable is not caught up (you can get replacement adjuster kits for $10 or thereabouts, and worth the peace of mind to have fresh parts). On one of my brakes I had to use a washer under the adjuster armature to keep it in position else it would flop out sideways and not engage. Once they are working correctly, manually rotate the screw until you get just a tiny bit of drag. Do the other side the same way, then set the parking brake so that the shoes are correctly set into position, then readjust the adjuster. With everything set correctly you should be able to feel the rear engaging.

I have not had much good luck with the auto adjusters in my 90 and 92. The 98 is too new to me to know. ehall took the time to explain in detail and +1 on that.

I may be flamed for this, but what's new! I put the rear axle on jack stands and put it in gear so the rear tires rotate. I then pull up on the ebrake one click at a time until I hear drag or one of the wheels stops. I then know that the two sides are not adjusted the same. Depending on how far up the ebrake lever goes before the sound or wheel stops, I will make adjustments to one side, then the other to match. I then know that they are close to being adjusted the same.

You need to apply the pedal brake several times between adjustments for the shoes to "set". Do this with the wheels rotating as the shoes may not set the same as like driving.

And if you do replace all the hardware, make sure it works as above- mine will periodically quit adjusting, and my braking will slowly degrade (about time to get in there and do it again, actually). My last new hardware kit was just as sloppy as my old parts, and it took some tweaking to make things work... for a while at least.

And quite a few people say just scrap the drums and go to discs, which is a good, although slightly more involved/expensive, alternative.

Good detail. I have tried backing up and stopping pretty abruptly but I'm not sure that has every made any kind of improvement for me.

How about the pull to the left and potentially having a bad caliper? Can you guys enlighten me as to how to tell if a caliper is bad? And would your recommendation be to go w/ an OEM piece or aftermarket parts store caliper?

I had an instance where, all of a sudden, on an Interstate at speed, I needed to slow down in a hurry, and the Jeep pulled hard left. Turns out the right caliper had just started to drag, heated up, and basically failed. I let it cool, drove home without incident on side roads, and found the rotor was blued from heat. The calipers (rebuilt), pads and rotors were about six months old, and now all needed to be replaced again. Possibly some air had expanded, causing the caliper to not release enough, causing the dragging pads. All of these brake parts are reasonably priced, and if you're unsure of the age or condition, replace 'em all, have a good baseline to work from. The rear drums can be made to work OK, it just takes patience. Start with all new/good stuff. Don't forget the lines. They will crud-up on the inside, just like they rust on the outside. The rears on my '92 were always marginal, until the hard line started leaking. Once I replaced it, WOW-I got brakes!. I've had the hoses going to the calipers and rear axle go bad, they like to clog, too.

I hate to recommend throwing cubic yards of cash at a problem,, but sometimes you either get lucky and figure it out, or open your wallet, and start dumping!

Well, I'm kinda fussy on some parts, others I don't give a hoot.

Brakes, I give a hoot--very steep hill bottoming out into a busy four way intersection + motorcycle + me + brake failure. I would go with quality only rebuilds or brand name new on calipers and wheel cylinders. It is pretty hard to screw up brake shoes or pads, I'm not a speed racer, so my XJ gets pad and shoes from just about anywhere.

Also, changing the flexible brake lines is a good idea and can restore quite a bit of braking power if they are so old they expand under pressure.

New rotors are cheap enough. I just picked up a pair of the Napa "Premium"s for 30$/piece. With your issue who knows how worn/warped your current rotors are.

uber xj said:

My plan is to resurface my front rotors (no slotted or cross drilled), bleed the brakes, and get new pads. I figure pads are the only aspect of this that will provide any improvement. So I want to know what kind of pads you are running and if they offered any type of improvement.

EBC? Auto parts store cheapys?

Click to expand...

Seems the hot ticket for front XJ/TJ/MJ/ZJ D30 brakes (on many of the other forums anyways) is the EBC Yelowstuff pads with Centric (non slotted/non dimpled/non drilled) premium rotors. I think this consensus was pretty much perpetuated by Van due to a post he made regarding all the various pads and rotors he's tried while fine tuning his Jeep Disk Kit.

My original plan on my '99 was to resurface the rotors but there just wasn't enough left to work with. I ended up buying a pair of the Centric rotors and a set of the EBC Yellowstuff pads. They just arrived yesterday and I should have time to put them on later this week. The Yellowstuff pads are supposed to offer increased stopping power for oversized tires, while still providing good stopping power when they're cold. Pretty much a perfect combination for off-road use. We'll see when I get them mounted up if they were worth the extra expense...

If you have to buy new rotors, make sure you get the right ones as mid year '99 was the split when they went from composite to cast rotors. I was able to find the composites for $30 without a problem, but the cast rotors were more in the $50 price range.

One of my planned mods is to replace the standard rear drum with the police special parts. You go from a 9"x2" with a flat drum setup to a 10"x1.75" and a finned drum to get rid of the heat. Parts can be found in the JY for cheap. Given the cost of used drums and resurfacing said drum, I'll go with a new drum as it is only a few bucks more.

Or you could just get a Dana 44 out of an XJ which comes with finned 10x2.5 inch drums and get a better axle while you're at it. They're relatively cheap at the JY as well and I'd imagine they're easier to find than an XJ with the Police Package. The thing that's never made sense to me about the 10x1.75 inch drums is that they actually have less surface area than the 9 inch brakes. I guess the fins may help, but it seems like additional braking surface would help even more.