Braking issues...

[Mel0]

Sorry if this is long winded but I figure the more info the better the answers. I recently purchased a 98 SR5 with 260,000 on it. One owner and all maintained at the dealer until 230,000 and then his daughter drove it for the next questionable 30,000. He was kind enough to disclose that the rear axle seals went out and needed replaced. So, I pulled off one of the rear drums and to my surprise, the shoes, drum and all hardware look brand spankin new, but, yes there is quite a bit of gear oil all over. My first question is, are the brake shoes still good after being saturated in oil? Can I clean them as best as I can with brake cleaner? This leads into the next braking issue. I have a moderate vibration between 60-70 in the steering wheel and feel a very noticeable shimmy/shake during hard braking. Is it a good bet to assume that the rear drums haven't been doing much stopping because of the oil making them so slick and in turn over worked the front rotors possibly warping them? I did rotate the tires and it improved the vibration at 60-70 but still have the shakes while braking. Also, the right lower ball joint boot is cracked out and I plan on replacing both but wasn't sure if there was any connection to the vibration. The plan is to replace the breather plug, axle seals, clean drums and shoes, replace front rotors and pads and finally the ball joints in that order. And on top of that I have the "thump" after hard stops and releasing the brake pedal... meaning the driveshaft needs grease? Other than all that it runs and drives like a top! Any help is much appreciated .

 

[OrangeTexan]

Take a look at this thread:

http://www.toyota-4runner.org/3rd-g...e-information-replacement-thread-3rd-gen.html

The rear shoes will need to be replaced. It is also likely that the thump is from the oil soaked shoes sticking to the drum after hard stops.

 

[LittleCaesar]

You have everything covered well.

I'd recommend both new OEM shoes as well as OEM lower ball joints. Also, when replacing the LBJs, get 4 new bolts for each side.

 

[Mel0]

Would the whole brake drum assembly need to be disassembled to replace the seal anyhow?

 

[Drcoffee]

Would the whole brake drum assembly need to be disassembled to replace the seal anyhow?

Oh ya. But its not as hard as it sounds.

 

[OrangeTexan]

Actually no. If all you wanted to do was replace the seal you'd only have to disconnect the brake line from the cylinder. No need to take the entire brake assembly apart. But like has been mentioned before - just replacing the seal only addresses the leak and not the oily shoe problem nor the washed out bearing.

 

[Mel0]

What do you mean by washed out bearing? If there is no noticeable play in the bearing will it be ok to leave it be?

 

[OrangeTexan]

When the axle seal is compromised there is only one thing keeping your brake shoes from getting the diff oil on them, and that is the sealed axle bearing. Once the brake shoes are ruined by the oil, we know that the oil has pushed its way past the seals on the bearing taking the bearing grease with it. So now the bearing grease is "washed out" and the only thing left lubricating the bearing is the diff oil. The bearing is not designed for this so its reliability is now an unknown and that is why we recommend replacing it. If this were not a concern then this whole process wouldn't require a press, and all that would be needed is new brakes and the axle seal. Too bad that's not the case!

 

[maddmatt]

Got the same "thump". It's the driveshaft needing grease.

 

[Mel0]

UPDATE:
So a few weeks ago I finally got around to replacing my leaking axle seals and the new ones seem to be holding up fine after about 1500 miles. The old ones were the original seal ending in 1 and were clearly shot. Definitely have some play in my bearings but it's not in my budget at the moment so I'll wait until it becomes a must-do. I waited to replace the drum shoes until I knew the seals were doing their job. The drum shoes were easier than I thought to replace. I didn't use any special tools either, just some channel locks, a couple long flat screwdrivers and few curse words did the job. Hardest part was getting the large spring at the top on and off... The shoes I used were Raybestos brand p/n 589PG which had the pin thingy already pressed into the shoes. I remember BFAD's axle write-up mentioned this being an issue with the AZ set he tried with no avail. The raybestos shoes were $30 or so and I think the toyota ones were more than $70. Replacing the oil drenched shoes got rid of most of the "thump" I was experiencing but still get it after a hard stop...next is replacing the single ujoint at the rear which was a very small amount of play in it and hopefully it will be all but gone. However, the pedal now feels a little soft, slowly travels about 2/3 to the floor. I used the old 20oz bottle with the hose submerged into the fluid method that I've seen done quite a lot. I did not let the main reservoir get too low and topped it off between the max and min lines. I'm thinking I'll re-bleed the brakes again but is there a better way to do it than with the bottle method???