New 199 TBU (under 500 miles) uneven braking getting worse!

[Arv]

This is not left to right brake pull or grab but it feels like uneven braking as the wheel turns. Like its grabbing more at a certain spot on the rotor. I suspect uneven bedding. I don’t get this when I brake medium to hard, I only feel this with light or very light brake pressure.

I make it a habit to check brake temps regularly after a brake job to make sure nothing is sticking or some other brake issue and temps are pretty much identical on both sides.

I “think” I know what a warped rotor feels since I’ve lived with it for over a decade, your steering wheel actually wobbles left and right as you feel the brake shudder/pulsation on your brake foot. I get neither but you can feel the slight jerking motion of the car as the momentum changes as the brake grabs then lets go a bit then grabs and lets go again as you slow/crawl to a stop. Can this be an early sign of warping?

This is the 1st time that I used Akebono ProACT pads or a brand that does not require bedding. Rotors are OEM, Powerstop reman calipers. I also did the rears with OEM pads and turned OEM drums the 1st time(about 1mm shaved off). Bled 3 times! I also used the same pads on a RX300 with no issues.

Could this be a result of bad wheel balancing? I had 265/65/17 Revo3 with less than 1000 miles that I just replaced last week with Open Country AT3s because they could not balance it right (60-70-ish mph shake), the OC AT3s are working a lot better with less road noise.

I did feel this problem almost from the get go (initially when you were really really slow and crawling to a stop) but its getting worse so I think the poor balancing couldn’t have warped the rotors that fast.

Can I just do an actual bedding procedure? OR do I clean and sand the rotors lightly and bed? I hope I don’t have to get the rotors turned. Sand the pads too? What grit(s) of sandpaper to use, crisscross pattern or circular when sanding the rotors?

Anyone experienced something similar?

Thx!

 

[shadow247]

Check for runout. Warped rotors don't exhibit this, but a single bent spot would.

 

[Arv]

Check for runout. Warped rotors don't exhibit this, but a single bent spot would.

I don't have the gauge/dial tool for this, might have to take it in to a shop or buy one for about $50+ online. thanks for the tip! Know of a lesser $$ alternative?

 

[LittleCaesar]

How well did you lube the pins, pad backing and ears?

The craziest culprit I have had for bad braking some years ago was a serious over torquing by a friend of his stabilizer links as well as his top bolt on his shocks. Got the right torque and his grabby braking as well as his ghost pulling went away for good. Also personally have experienced weird braking issues due to bad ball joints, as well as control arm bushings.

Don’t know of another member who has been on here since 2003.....

 

[Arv]

How well did you lube the pins, pad backing and ears?

The craziest culprit I have had for bad braking some years ago was a serious over torquing by a friend of his stabilizer links as well as his top bolt on his shocks. Got the right torque and his grabby braking as well as his ghost pulling went away for good. Also personally have experienced weird braking issues due to bad ball joints, as well as control arm bushings.

Don’t know of another member who has been on here since 2003.....

I used the black CRC Synth grease liberally or a lot! So we can probably exclude parts binding but I can check for that too.

As for torque-ing, I have two 1/2" torque wrenches (I used one to check the other, better than nothing ) so I think I got them right when I did the brakes and the Tundra Billy 5100 and 99 talls last Fall.

As for the rest of the suspension, had it aligned after the work so everything should be good. You know those lifetime alignment shops, they point out every issue because they think they can make money off replacing them.

Really? I had my 2k Sport since it was brand new. I probably went on here in 2003 because of my aftermarket wheel balancing issues that I've had ever since!

edit: It only has 130K miles, just did a tune up, rear axle seal and bearings, tranny 14 quart fluid exchange, and x-case and frt and rr diff d&f to synthetic. Plus the new brakes and suspension and some poly bushings, so it feels like driving a new rig except for this braking issue :-(

 

[Bad Luck]

This is not left to right brake pull or grab but it feels like uneven braking as the wheel turns. Like its grabbing more at a certain spot on the rotor. I suspect uneven bedding. I don’t get this when I brake medium to hard, I only feel this with light or very light brake pressure.

Anyone experienced something similar?

Thx!

I had a similar feeling due to rear axle seal leak. Try pulling the parking brake handle while holding the button down while driving around 40 mph and around 60 mph, or whatever speed you've been noticing it the most. If you get the grabby feeling or a slight vibration then the problem is the rear brakes.

In my case the rear axle seal leak was causing one part of the drum to get some gear oil on it and that spot wouldn't grip like the rest of the drum causing a slipping/gripping situation.

 

[Arv]

I had a similar feeling due to rear axle seal leak. Try pulling the parking brake handle while holding the button down while driving around 40 mph and around 60 mph, or whatever speed you've been noticing it the most. If you get the grabby feeling or a slight vibration then the problem is the rear brakes.

In my case the rear axle seal leak was causing one part of the drum to get some gear oil on it and that spot wouldn't grip like the rest of the drum causing a slipping/gripping situation.

Just did the rear axle seal and rear brakes too. I cleaned with Acetone then brake cleaner. So it "shouldn't" have an oil spot. I even checked if the ABS tone ring was still dry last week using a WIFI borescope. Pretty cool device that I've used to check engine cylinders through the spark plug hole.

I will try pulling the e-brake just to confirm that its not the rear. thanks!

BUT this might be somewhat the case in front, if some of the brake grease got on a spot on the rotor!

 

[LittleCaesar]

As [MENTION=319302]Bad Luck[/MENTION] says, definitely check your rears. They may be out of adjustment. How did the brake fluid look when you bled the calipers?

I take it that with the old calipers and pads you didn’t feel this problem.

A pic or two in the future would be cool....

 

[Arv]

As [MENTION=319302]Bad Luck[/MENTION] says, definitely check your rears. They may be out of adjustment. How did the brake fluid look when you bled the calipers?

I take it that with the old calipers and pads you didn’t feel this problem.

A pic or two in the future would be cool....

We took the time to adjust the rears and even bled 3x to get all the micro bubbles out and get that nice bite early with just light foot pressure. It was still pretty deep/low even after 2 bleeds. At first I thought one side was over adjusting because of a temp diff between L and R rear temps but I realized the temp varied around the drum so it was ok. I can pull the e brake easily around 7 clicks within specs.

Here's a quick pic I took before changing into the OC AT3s, rig is dirty I really like the Whitson rack,my wheels (these are the revo3s), and the black piping vs. stock body color makes a huge difference! Tacoma whip antenna looks great too.

 

[Falonious]

Arv,
Sweet rig my friend. Looks real nice.
Can't really comment on the braking issue as you've done everything I would have so far. Just wanted to compliment you on taking such good care of her. :hail:

I'm sure you will get it sorted out.

 

[Arv]

I had a similar feeling due to rear axle seal leak. Try pulling the parking brake handle while holding the button down while driving around 40 mph and around 60 mph, or whatever speed you've been noticing it the most. If you get the grabby feeling or a slight vibration then the problem is the rear brakes.

In my case the rear axle seal leak was causing one part of the drum to get some gear oil on it and that spot wouldn't grip like the rest of the drum causing a slipping/gripping situation.

So based on what you said, I pulled on the handbrake at about 5-10mph or when about to crawl to a stop several times and I did feel the problem on the handbrake handle and it even felt that the handle was going up and down a little bit. Then I finally had the time to remove the rear drums. It looks like the new OEM shoes have a bump in the middle (or convex) top to bottom lengthwise so its only making contact with the drum surface in the middle.

You can see this clearly on the pictures. It looks like the middle of the front shoes are starting to mate with the drum but the top and bottom looks like its got a long way to go.

So I think the rear brakes need to go through a rigorous bedding procedure.

The question is, do I need to remove the brand new OEM shoes and sand them down with a foam block with 100-150 grit sand paper or bed them as is after cleaning with brake cleaner?

Or I think I might be able to sand them w/o a foam block in place.

Thanks!

 

[Arv]

Also from the black residue/brake dust. I don't think we cleaned the drums well enough and there was still some oil left on the drums.

 

[Bad Luck]

Also from the black residue/brake dust. I don't think we cleaned the drums well enough and there was still some oil left on the drums.

If there was any oil on them I would pull the rear wheel speed sensors and spin the axle around to see if there is any oil on the abs tone ring or if you can see any in the axle tube cavity. Any oil in there is an indication the you have a failed rear axle seal.

If you do that on both sides and don't find any oil then I would have your rear drums turned again. Even with only part of the rear shoes contacting the drum that shouldn't cause a vibration/catch and slip feeling unless the drums have oil residue spots or are still out of round.

 

[Arv]

If there was any oil on them I would pull the rear wheel speed sensors and spin the axle around to see if there is any oil on the abs tone ring or if you can see any in the axle tube cavity. Any oil in there is an indication the you have a failed rear axle seal.

If you do that on both sides and don't find any oil then I would have your rear drums turned again. Even with only part of the rear shoes contacting the drum that shouldn't cause a vibration/catch and slip feeling unless the drums have oil residue spots or are still out of round.

Rear seals and bearings are new, I also use a borescope to check thru the ABS port so I don't have to pull the wheels off! Great tool!

I want to give the tech at Les Sw the benefit of the doubt specially with those self centering hubs for the lathe but you never know they might have rushed the job or it didn't center. I guess even if the shoes were convex it should still be the same area in contact with the drum. Plus the shoes are "soft" compared to the metal drum so it should easily shape to the drum. I've never had drums turned before, I either get a new one or slap them back on so I've never had experience with this.

However, I never really bed my brakes, since the ProACTs pads didn't need it, I forgot about the rear shoes! How many people actually bed their rear brakes????

Well since I already have the drums off, I can ask them to mount it on the lathe and we can immediately tell if its scraping unevenly.

thanks!

 

[Arv]

Update: brought back my drums and they turned one again, the other was going to be below spec so they couldn't turn it. I'm almost 100% they messed up the job as the drums only had 130k miles on them. Plus obviously if they thought one drum needed turning again because it was out of round then they didn't do it the first time. Had to argue my point to get my money back! Now I'm looking at new aftermarket drums. Any suggestions?