4WD braking issues

Hi new here,
I have a 2010 Tundra Limited double cab with 180k miles, well serviced that I just bought. It recently snowed so I started to use 4H which works great until I start braking down hill(only using in icy subdivisions), it shutters with vibration in the brake pedal and wont allow me to apply full break pressure. I have no issuse when in 2WD anywhere just curious if this has happened to anyone else or what I might look into for a fix?

 

Welcome from Ohio.

 

Welcome to the party!!

No help on issue here. Dont get a whole lot of ice or snow in TX

 

Hiya and welcome from SoCalif!!!

 

Sounds like abs kicking in. Maybe your abs module needs to be bled. Don’t know why it only does it in 4wd though. If you go to a good mechanic they can cycle the abs while bleeding your brakes.

Or go to a gravel road and slam on your brakes (safely) a few times to get it circulating.

 

Its a known issue that ABS over reacts on very slippery surfaces. Your only options are to increase traction (snow tires and/or studs) or pull the ABS fuse and use brakes without ABS

 

OK I have to ask. Are all your tires matching?

 

Welcome from Northeast Connecticut

 

Welcome from SE PA!

 

Welcome from Sin City

 

Wow thanks gor the fast replies I will try it with traction control off and see how that goes, it did feellike something took over a bit. I originally drove a 97 wrangler that now sits in the garage, this things a spaceship conpared to wrangler. The only tracion control I was ever used to was the boulders beneath me. If traction control doesn't help I'll have the brakes and abs taken care of. I'll let you know how it goes.

 

Welcome from Obx

 

Just so you know.
Hit it once and it engages simulated LSD.

Press and hold for three seconds and it engages LSD and turns off traction control as well.

Once you’ve done that press and hold for an additional three seconds and it turns back off simulated LSD and turns off stability and traction control. This step is as nanny free as you can get without pulling a fuse.

 

Welcome from Texas

 

It's not the traction control, it's the ABS. Turning off traction control won't change it.

ABS works by pulsing the brake pressure to avoid a tire locking up when on a slippery surface. Think about ABS on a trailer, where the tires aren't being driven--it works without any interference between the wheels, and each wheel can be individually modulated.

When you're in 2WD, the front tires aren't driven and can be individually modulated, and the rear tires, while driven, are connected by an open differential so they can also be modulated relatively independently.

When you are in 4WD, however, you are creating a mechanical interlock between the front and rear tires. What you're experiencing is the ABS trying to modulate a given tire or axle to avoid slipping, but that braking force is also being transmitted to the other axle via the drivetrain. If a rear tire is on a slippery surface and the front tires are on a surface with traction, when you hit the brakes the ABS may sense the rear tire locking up, and try to pulse the brakes to avoid lockup...which is transmitted through the rear axle, rear driveshaft, transfer case, front driveshaft and front differential/axles to the front wheels, which are then pulsing on a hard surface. The transfer case is just transmitting the pulsation to both axles, mechanically.

ABS works theoretically best when each wheel can be independently modulated. 2WD is as close as our trucks come to that. 4WD just causes the function to be a bit different. While it seems odd, if you want the ABS to function, the best way to descend a steep/slippery hill is in 2WD...otherwise, the 4WD can cause all 4 tires to lock up--especially if you use engine braking.

 

Are you some type of Engineer/brake specialist? Great explanation

 

Ok so I've been out and about trying 4wd and 2wd it does the vibrations in both but only on slick surfaces, it feels like gears are rolling when I brake I'm guessing thats the abs kicking in or not working correctly? It doesnt allow me to press the pedal down all the way when it happens is that due to bad abs?

 

Nothing wrong with your ABS.
When it’s slick and you brake abs takes over and doesn’t let you fully apply on your brakes so they don’t lock up.
It prevents skidding and allows you to maintain steering control
Antilock brake system.

 

Alright gents and any ladies that are on here! I just bought a 2017 Tundra SR5 with 28,743 miles. I drove about 32 miles to my home. Before I got home I stopped at a gas station and when I applied the brakes a clank sound happened. Then the brakes sounded like they were grinding on the rotors. I called the dealership that I bought it from and explained this. I'm taking it back tomorrow to have them look at it and fix it. I just wanted the opinions from you all and not sure if this is the right thread.

 

Welcome dark0ampoule! New here too but had a similar issue with my wrangler and the brake solenoids were going out just a thought.

 

Ok, the tech got in and asked me to explain what was going on. I told him. We didn't even make out of the parking lot, literally he backed up heard noise and then drove forward and applied the brakes. The truck sounded even worse than last night. He said oh yeah, I'm gonna let you out here and pull it straight into the service area.

 

Update: The lead guy in the service department said that they resurfaced the rotors, put new pads on the front and greased the rods or shims. (Pretty sure he said rods) He stated that they were causing the pads to stick. Everything else has checked out with the vehicle. Onlytimewill tell, but damn I sure do like this truck. Also, I did get an extended warranty through my bank.

 

Not the same issue as this .. OP is just experiencing ABS.