About to burn this truck. Someone help me please!

Hey crew.

Long time lurker here. I bought A 2009 Tacoma in 2019, I got the truck, and Toyota replaced the frame, the leafs, and the shocks shortly after due to a recall. Since then I've put 230k miles on it. I replaced all the front end components about a year ago, around 200k miles. I also replaced the shocks, and went to bilstein 5100s. I had a driveline shop here in Knoxville make me a new driveshaft with a dropped carrier bearing for my lift. Im Running 35s, with a big custom off road bumper I made, some side steps, a full exhaust, aftermarket wheels, and the truck is spotless. I replaced all the brakes, Brake drums, shoes, front calipers, pads, rotors, etc.

Two issues currently. A few weeks ago I heard a grinding from the rear end of the truck. Right side. Sounded very very wheel bearing ish. took it to toyota, and they said it needed 3 wheel bearings.

So, I ordered them, jacked it up, started changing them all. I had new axle shaft bearings pressed onto the axle shafts, and ordered new hub assemblies as well. Went ahead and threw new cv axles and pads on the front and then bled everything.

Now my current two issues.

Whatever that damn grinding is, I cannot find it. It is loud as hell. The rear end is completely fine, even Toyota said so. Ive replaced anything that could grind, so Im at a loss for words here.

Second problem, No matter what I do, or how many times I bleed the brakes, after I drive 300ft down the road, I have no brakes.

I've babied this truck, and its always been good to me, but now im starting to get frustrated. I just put $1500 worth of parts on it and its still making the noise. I've never ran into this problem. Also, no, the drums are not warped, they are new, and with the wheels off and snugged with lug nuts, they rotate freely, and quietly.

Thanks ahead of time!

 

Does the grinding sound happen with the rear wheels off the ground in drive?

As for the brakes, if you got air into the ABS module, you'll need a scan tool to bleed the brakes.
Did the master cylinder ever go dry while you were installing the rear axle?
The brake line has to be disconnected to pull the axle. How much fluid did you loose then?

 

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sub'd

 

Also, what do you mean by "have no brakes"? Please explain a bit more so we can help.
For the grinding, when you drained the rear diff fluid, did it have any glitter in it?
Have you verified that your front dust shields, behind the rotors, are not rubbing? Grinding sounds can be deceptive relative to location.

 

Never touched the module, Master cylinder never dropped even a little. I plugged the ends of the lines immediately upon pulling them.

Grinding sound happens always.

 

I have confirmed it wasn't the front dust shields. That's what I originally thought it was, but its coming from the rear right of the truck. And by no brakes, i mean I literally have no brakes. But when I bleed them, no air is coming out of the system at all, master cylinder is topped off. I've gone around the entire truck a few times and I'm getting no more air. Obviously there was air to start, but no more air is trapped in the system, that i can tell.

 

I know this might sound strange but, have you checked your exhaust and exhaust heat shields?

 

This does not sound strange.

The last of "fixes" and or upgrades are that my exhaust tips need replaced. I've looked from every conceivable angle and idk what they could be hitting on to make a grinding sound. There are no shields under my truck. Guy that had it before me offroaded quite heavily in its first 25k miles of life I believe, and he had removed them, or someone else did and sold them for scrap. My exhaust tips are rusted through, but that is literally the very last on my to do list. But it isnt that, that I know of.

 

Brake issue - I would recommend checking to make sure that all brake line fittings are tight/not leaking in areas you touched them, if all that's good have a dealer or indie shop do a complete abs brake flush using a scan tool.
Grinding noise - does the noise only happen when the vehicle is driving, when about when going in reverse, can you jack up each wheel and easily spin it by hand, does the noise start or stop at particular speeds, does it change turning left or right?
The more info you can provide the better recommendations can be provided.

 

Starts at 15mph, nothing stops it after that. Not hitting the brakes, turning, reversing it happens at 15mph too, nothing stops it.

 

Wheel cylinder?

 

Mayhap the exhaust is resonating some loose crap in there.

Master cylinder might be bust on brakes

 

You've put it in neutral and reverse the engine slowly to make sure its not engine related? Does the brake pedal pulse? Just thinking maybe the ABS is unhappy and those pumps can make strange noises. Any warning lights on? Does the noise pitch change with speed or is the noise frequency constant regardless of speed?
Edit - Don't hit the brakes, just very very lightly apply them, I have a weird vibration noise that I chased for about 2 hours before figuring out one of the brake pad anti rattle clips was loose causing a rattle, it went away when I very lightly applied brakes was my (eventual) clue.
If its a bearing, wheel or driveshaft, the frequency should change somewhat depending on vehicle speed.

 

Definitely get a shop that can cycle the abs pump to exchange brake fluid.

As far as the grinding, could the custom driveshaft, carrier bearing, or U joint be in play? How is your pinion angle? Could the pinion bearing be worn? Could the ring carrier bearings be worn? Does the pitch of the grinding change with wheel speed or engine speed? You may just have to carefully look at everything that rotates.

Edited for a huge number of autocorrect mistakes

 

Nope, wheel cylinder is fine.

 

Idk, Would it sound grindy?

 

It gets louder after 15mph, but doesnt start until then, and nothing else changes it.

Zero warning lights anywhere in the truck. Idk whats going on with the brakes, i've never had any trouble bleeding brakes before, and they worked fine before this.

 

Checked all these things today. The new driveline has less than 20k miles on it, its all as tight as the skin on a grape.

 

So when you have the no brake issue, is the pedal going to the floor, or is there pressure, but no feeling of braking relative to the truck slowing down?

 

Bleed your brakes again....