2006 DC - Brake and vibration issues

First road trip this weekend with new-to-me 2006 DC RWD. Pretty good trip, but must tackle issues noted:

• Parking brake does nothing, no engagement, can idle down street with pedal fully depressed
• Slight shudder/pulse noticeable at cruising speed all the time
• Significant shudder on braking, especially downhills - cab vibrates
• Weak pedal, poor brake performance, initial engagement lower than it should be - noticeable in traffic too
• Hideous creak/squeak over slow speed bumps - control arm bushings, lower and maybe upper, maybe other bushings

Been cruising threads (paging Aerindel!) and could be up against a number of problem areas - Brake issues front/rear, alignment issues, bearing/bushing/steering issues. Where to start? Got my hands dirty tonight and looked at parking brake. Two obvious issues:

1. The Automatic Adjusting Lever for parking brake/rear shoes is missing from both sides! Somebody just left these off!
2. The Parking Brake Lever on driver's side doesn't return after actuation

Drums and shoes well within life limits - there is dust, but low wear like maybe they're doing nothing. No obvious rear axle bearing play when shake wheel/drum. Carfax history shows pro service for this truck, front brakes done approx. 25K back. No history for rears. I manually adjusted the shoes until drums just fit with interference, but obviously need parts in back plus additional diagnostics.

Plan was to isolate shudder to front or rear. What's next step - get all new kits and adjusters for rears? What causes the Parking Brake Lever to return/spring back in the rears? Is it just the shoe adjuster and return spring?

 

I’d get new OEM shoes & hardware. Have the drums turned (I replaced mine- oem) check the parking brake cables for corrosion, lube them where necessary. Adjusting the rear shoes correctly will help the pedal free-play. You will likely have more free-play then other vehicles, but the brakes will work fine.

On the front, probably new rotors (I used Brembo) and new pads (Toyota Ceramic) Check the front wheel bearings.

Bleed the brakes (I prefer a vacuum style bleeder) use a good quality brake fluid (I use Valvoline Synthetic Dot 3 & 4)

 

This is how I found driver's side - adjusting lever is missing. But parking brake lever didn't spring back either. See free play in the cable? Springs back fine on the other side. Is it just the adjuster and shoe return spring that should make the parking brake lever return? So full rebuild of rear drums seems reasonable to be sure all well. Then move on to braking performance and shudder diagnosis?

 

The nut at the end of the cable should be tight to the parking brake lever.
As I recall it took a bit of work to connect. It’s a short cable, check the other end, it’s probably not connected.

 

Here's some pics of mine.

 

Thanks very much. Cable does seem connected, and parking brake cable actuates when you move the bellcrank manually, or just actuate lever with fingers - it just doesn't return.

Are you missing automatic parking brake adjusters too in those pictures? Was expecting parking brake to actuate the star adjuster?!

 

It’s on the backside of the star wheel. You can see it in the 1st pic underneath the brake cylinder dust cover.

 

Welcome.

I see that you must of read one of my other posts on the tundra rear brakes.

First off, yes, I would start with a full brake kit, they are not very expensive and that way you know you will have all the parts and they will be in good condition.

As for not springing back on one side, check the short levers on the back of each brake backing plate (The parking brake bell crank in your diagram), those can get rusted in place and not move. The same goes for the 'splitter' lever mounting on your axle that the main brake cable connects to before it splits off to each brake. That can also get rusted in place, if it can't move, only one side will work.

The two springs on your bell crank should be what holds tension on the parking brake, although obviously it is very loose they will bottom out before they pull the cable tight.

You may need front brakes as well but until you get your rear brakes in order nothing else is going to work right either and with your adjusters missing we know for sure you have at least one problem there.

As I mentioned in another thread, your front and rear brakes share a hydraulic circuit so rear brakes out of adjustment will result in more pedal travel and reduced braking all around.

And the proper way to get that adjustment is with a properly functioning parking brake which is what makes the auto adjuster actually work.

These are the parts I referenced that can rust and stick and keep the cable from returning:

 

https://m.youtube.com/watch?v=6wjT8Iz43zk

 

Interesting, must be a difference with the later models, on my 2000 the adjuster goes over the front of the star.

 

I replaced the way I found it. Maybe I should check it.

 

2006, the star adjuster is on the back

http://www.oem-cycle.com/2006Tundrarearbrakereplacement.shtml

 

On my 2000 it should looks like this:, I can't speak for later models. It may be perfectly correct for your year.

 

Good info....anyway...present or not, it won't self adjust without the parking brake working so thats where the OP needs to start. Unless that is also different on the 2006.

 

Aha! Yes - good info. Thanks SoCalPaul. Manual page shows adjuster arm on front of parking lever, arm moving up to engage star adjuster - Toyota moved it to back of other side, arm moving down. Was expecting to see it right in front - wonder if there's a manual page outlining this.

Anyways - first step is get these rears clean and with new hardware, then will diagnose shudders, etc.

 

I had a issue with my brakes kinda like the one you mention and it ended up being one of the front calipers sticking. A easy way to check is after a drive take the temps of the rotor with a IR temp gun and see if there is a large difference in temps between the drivers side and passenger side.

 

Very good - just completed test drive and will get the IR gun out and check that.

Re-did the rear drums last night with Toyota shoes and aftermarket spring kit, tightened up the parking brake actuation. Drums seemed almost new and clean. Also replaced a wheel cylinder that leaked as I was refitting shoes. Found air in both rears while bleeding and pedal feel MUCH better now. And with parking brake test, shudder is NOT in the rears. However:

- Parking brake is still weak - won't completely stop truck at idle, for instance. Will tighten adjusters further and see if can improve. What should I expect?
- Overall braking performance at speed is poor. Still feels like rears not doing enough.
- Shudder in front, very noticeable from 50+ mph stops. Wheel initial move is always to left, then vibrate back/forth.

So will start looking at other issues up front. Control arm bushings are ready for replacement. Could fool around with LSPV adjustment, but not excited to try.

ETA: IR temp test with a few heavy braking events - Front 250F L / 300F R. Significant but not huge difference. Will look at caliper. Rear drums both approx. 180F (seems kinda cool).

 

I've had a few stuck calipers in my time, and the difference was usually dramatic, 120º in one....500º in the other after a short drive.

But its something to check, it certainly happens and causes problems.

Even though your brakes are a little different than mine I believe they auto adjusters work in the same way? have you checked that the parking brake moved the adjuster? I know that in some models they are adjusted when you brake while driving backwards.

My parking brake did almost nothing after I initially replaced the drums and hardware. I thought shoes where adjusted properly at that time but after I thoroughly went through and tightened all the parts of the parking brake I was able to get half a dozen more clicks out of the adjusters by pulling on the parking brake cable and that made a BIG difference.

The thing to remember about the parking brakes is that the whole system amounts to a lever which moves about 12" on the pedal end, and about 1mm on the other but with much much more force. But if that shoe is 1mm away from the drum all of that force gets used up before it can come to bear so that last tiny faction of an inch of spacing is what makes or breaks the brake system.

And while you can eventually get the shoes adjusted by trial and error its rather hard compared to fixing the parking brake system so the auto adjuster works.

The parking brake should be more than enough to hold the truck still at idle. I think on mine I have to get the RPM up to 2000 or so with the brake on before the truck will start to move.

 

Follow-up for future reference - some DIY and some shop work sorted these issues. Truck great now - on to next issues. I did brake stuff, but shop for bushes, balljoints, and alignment.

• Braking - new Toyota brakes all around and parking brake so adjusters work in rears - MUCH better now, no mushy pedal, confident and predictable stops
• Big shudder on braking and downhills - Steering rack bushings were allowing rack to shift. New bushings and alignment
• Hideous squeak over slow speed bumps - new lower control arm bushings, originals torn. Also upper ball joints replaced with Toyota. Drivers side was loose. Current front Unity struts make a little noise, but acceptable for now.
• Slight steering shudder at cruising speed all the time - improved now, but still can be felt on highway. Likely due to cheap tires. Will balance or replace in future.

For next problem - infamous 1st Gen driver's seat broken/rocking. Looks like a pain to fix. Let me know of threads or links with a solid solution.

 

I've honestly never heard of this problem. What part of the seat broke?

 

That's a great video. Thanks for posting.

The one thing I'd add to it though: while you have everything off, remove the parking brake bell crank (just two bolts) clean it up, grease it, and re-install. I recommend a good waterproof marine grease. Up north, those things rust up so quickly, it's just good preventive maintenance. If you do it while performing the brake job, it's so easy to do it properly. If you have to do it after the fact, it's much harder, and you really can't do a thorough job unless you remove the bell crank from the backing plate -- which requires basically duplicating all the labor of a complete brake job.

 

The right side of the driver's seat rocks under load, can move back under acceleration then 'click' back forward. Or just move as you get in or adjust weight. Very annoying and possibly a seat integrity safety issue. Apparently occurs with both manual (like mine) or automatic seats. Doesn't occur for me when you jack the seat up, only when in lower third of height adjustment.

Found various threads on other sites - 'tundra loose drivers seat' or 'tundra seat rock fixed'. Others chiming in with same issue. The shop actually used a endoscope inside the seat frame to analyze - like a frame design issue cracking or bending relative to the jack screw assembly. Toyota seat frame replacement (like $900) has been tried, but often reoccurs anyways. One poster "fixed" by pre-loading the right rear mounting point with a couple washers.

 

Yeah I have this issue, too. I think it's a DC (and maybe Sequoia) issue only.