Shaking when braking over 40mph

Tiny
IASALAS24
  • MEMBER
  • 2011 TOYOTA 4RUNNER
  • 29,500 MILES
When driving over 40 mph and braking the 4runner grinds from the rear. Its terrifying to me and especially more so when my wife is driving. This cannot be safe can you show me how to do brakes on the back please? Thanks
Monday, May 6th, 2013 AT 12:25 PM

10 Replies

Tiny
DANNY L
  • MECHANIC
  • 5,648 POSTS
Here is a video to help you step by step with instructions in the diagrams below to show you how on your car.

https://youtu.be/r82BLijWuNQ

Here is a YouTube video from our site on how to compress the rear caliper piston when performing a rear brake job:

https://youtu.be/j8YwfSKEzZo

I've attached picture steps below on how to replace the brake pads on your truck. Hope this helps and thanks for using 2CarPros.
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Wednesday, March 31st, 2021 AT 10:50 PM
Tiny
CHEECHBABY
  • MEMBER
  • 1 POST
  • 1998 TOYOTA 4RUNNER
  • 6 CYL
  • 4WD
  • AUTOMATIC
  • 178,000 MILES
What does it mean when there is oil leaking into your rear brakes?
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Monday, April 12th, 2021 AT 9:43 AM (Merged)
Tiny
OBXAUTOMEDIC
  • MECHANIC
  • 3,711 POSTS
You will need to change the Brake Shoes and Axle Seal of course. You can get some Brake Cleaner to clean all other parts in the Drum.

However, you will need to remove the axle from the housing in order to replace the seal....


https://www.2carpros.com/forum/automotive_pictures/188069_98_4runnerrearaxle_1.jpg



What other questions do you have?
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Monday, April 12th, 2021 AT 9:43 AM (Merged)
Tiny
KBEST
  • MEMBER
  • 1 POST
  • 1997 TOYOTA 4RUNNER
  • 6 CYL
  • 2WD
  • AUTOMATIC
  • 176,000 MILES
I just got my rear brakes (shoes) replaced and new drums on my '97 Toyota 4Runner. They weren't squealing or going all the way to the floor, but hadn't been replaced in the past 8 years. Shouldn't I be able to tell a difference in how the braking feels with the new parts?
Thanks!
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Monday, April 12th, 2021 AT 9:45 AM (Merged)
Tiny
PROTECH1980
  • MEMBER
  • 901 POSTS
Are you having a braking problem now? If the brakes where properly adjusted before and were just replaced because of age, the new brakes (being properly adjusted) wont feel much different.
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Monday, April 12th, 2021 AT 9:45 AM (Merged)
Tiny
CARADIODOC
  • MECHANIC
  • 33,871 POSTS
Absolutely not. In effect what you're saying is the brakes should have been worse with the old shoes, and who would want that? Manufacturers spend a lot of research time and money developing brakes that are balanced front-to-rear for a specific vehicle's weight distribution. Part of the variables has to do with the coefficient of friction between the linings and rotors and drums. It is very important that replacement linings from any manufacturer maintains that same coefficient of friction. Companies that advertise better stopping power are misleading you. No one wants rear brakes that stop better than the front ones. That means they'll lock up easier, and skidding tires don't have traction or stopping ability.

What you MIGHT find is most brakes require less pedal effort after about a 100 mile break-in period. New linings and new or machined rotors and drums have microscopic irregularities that will wear away over time until the friction surfaces match perfectly. That's when their performance will be the best. Until then, understand that the new brakes will not perform at their best. It is fairly common that this means you will have to push the brake pedal harder to stop. Many shops warn you with tags hanging from the mirror to go easy for a few days. Pushing harder on the pedal to get the vehicle to stop will overheat the linings and lead to one type of brake fade where the pedal feels fine but the car just keeps on going. That means out of desperation, you push even harder and the problem gets worse until you have no brakes at all. If that happens, the only but proper fix is to let the brakes cool down for an hour or two, then drive like normal. The friction will come back when the linings cool down, and by that time the problem will likely never show up again.
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Monday, April 12th, 2021 AT 9:45 AM (Merged)
Tiny
PROTECH1980
  • MEMBER
  • 901 POSTS
Hey Caradiodoc, Happy Wednesday, thanks for the detailed info.
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Monday, April 12th, 2021 AT 9:45 AM (Merged)
Tiny
MATTHEW SIMMONS
  • MEMBER
  • 1 POST
  • 1997 TOYOTA 4RUNNER
  • 3.4L
  • V6
  • 4WD
  • AUTOMATIC
  • 278,100 MILES
I watch your video about how to change the rear brakes and wanted to know what tool you used to remove the the lock springs to hold the shoes on? Also, why you need to bleed the brakes after the job is done if you did not undue the brake lines?
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Monday, April 12th, 2021 AT 9:45 AM (Merged)
Tiny
CARADIODOC
  • MECHANIC
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You do not have to bleed the system if nothing was opened that would allow air to get in. A normal part of replacing shoes is to inspect the wheel cylinders behind their dust boots for signs of leakage. If that is found, the wheel cylinder must be replaced, then just that wheel has to be bled.

In the 1980's, it was common practice to rebuild calipers and wheel cylinders on every brake job. That is less common today, but when it is necessary, professionally-rebuilt calipers and new wheel cylinders are so inexpensive, the kits to rebuild them cost almost as much, plus you have to add in the labor and special tools. Rebuilding these parts is best left as a last resort when that is your only option. Unfortunately there is fewer and fewer people who know how to do that.

There are precautions to observe when working with brake fluid. The first is to be extremely careful that not a singe drop of petroleum product gets mixed in with it. That will contaminate the entire system and cause rubber parts to swell. The only proper repair for that is to remove every part that contains a rubber part that contacts the fluid, flush and dry the steel lines, then install new rubber parts. That includes rubber flex hoses, calipers, wheel cylinders, master cylinder and its rubber bladder seal under the cap, combination valve, and when used, the rear height-sensing proportioning valve. That repair can cost more than what the vehicle is worth, and it is a lot worse if it has an anti-lock brake control valve assembly. Petroleum products include engine oil, transmission fluid, power steering fluid, gear lube, axle grease, and penetrating oil. Brake system specialists even wash their hands with soap and water to avoid getting fingerprint grease on rubber parts and on friction surfaces and linings.

The second concern is to never push the brake pedal over half way to the floor. I never trust a helper with pedal-bleeding, especially if that is an inexperienced, new mechanic. I only do gravity-bleeding. This is to crack the cap on the reservoir so vacuum will not build up that inhibits fluid flow, open all the necessary bleeder screws, then just wait for one to start flowing. If none do that after five minutes, push the brake pedal by hand an inch or two to get the flow started. That is only necessary if the reservoir was allowed to run empty and the entire system is out of fluid. When fluid flows from one bleeder screw, close it and wait for the next one to start flowing. When all the bleeder screws are closed, "irritate" the brake pedal by hand a little. That will wash any stuck bubbles into the calipers and wheel cylinders. Open each bleeder screw once more to burp those last few bubbles out.

The reason for not pushing the pedal over half way is crud and corrosion build up in the bores of the master cylinder where the pistons don't normally travel. Pushing the pedal over half way runs the rubber lip seals over that crud and can rip them. That results in a slowly-sinking brake pedal, and that may take two or three days to show up. When we get a car in with a popped flex hose, a lot of shops automatically include a rebuilt master cylinder in the estimate, assuming the surprised driver pushed the pedal to the floor. This damage is commonly caused by do-it-yourselfers and inexperienced mechanics when they pedal-bleed the system.

As for the tools, since you listed "beginning mechanic", it is time to start investing in quality tools. Just like with doctors and carpenters, when you make your living with hand tools, the more you buy that you will use, the more productive you will be. If you are paid on flat-rate, this is the fastest way to earn more dollars per day. If you are in one of the few shops that only pay by the hour, higher productivity will be rewarded with promotions and pay raises. Start by looking at the online catalogs for Mac, Matco, Cornwell, and Snapon Tools. All of these will have lifetime warranties. Professional mechanics will not put up with cheap quality tools, and since these guys show up at each shop one a week, they will not be selling junk. You can also stop in on these trucks, but if you are not working at a shop yet, the mechanics at any shop can tell you when they stop at their shop. It will usually only be for an hour, and at some places the mechanics are on their lunch breaks, and at some their time in the trucks cuts into their earning time, so the salesman will have to take care of them first. You might have to wait until the end of the hour, then the salesman will be happy to answer any questions and show you what is popular.

Also, consider stopping in at a Toyota dealership and asking one of the brakes specialists what he uses most often. The most common tool looks like a screwdriver handle with a round cylinder on the end to push and turn the caps on the "nails" holding the shoes to the backing plate. You can do the same job a little less elegantly with a regular slip-joint pliers. There are a variety of spring tools that will include a grooved shaft to wind spring hooks off their anchors and to lever them back on.

Look at S14AP and S13P in the MAC online catalog. S13P has the grove on the right end for prying return springs onto the anchor pin and the left end goes over the anchor pin, then is rotated to wind the spring off. It has been a long time since I bought tools, and I was surprised at the prices. Given that there is not much that can go wrong with these, Harbor Freight Tools will have less-expensive versions. When I started in the early 1980's, these two tools came in a kit of brake tools from Harbor Freight Tools for $12.95. I still use them today. A coworker bought the same kit in the same plastic tray in the same box, with the Snapon name on it, for $109.95!
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Monday, April 12th, 2021 AT 9:45 AM (Merged)
Tiny
CARADIODOC
  • MECHANIC
  • 33,871 POSTS
Item number 188 from Harbor Freight Tools is the set I bought a long time ago. Price is still real good.
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Monday, April 12th, 2021 AT 9:45 AM (Merged)

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