Truck jumps while braking

When I stop at a red light or stop sign I depress the brake peddle and the truck sort of jumps a bit. Any ideas what to check.My truck is and 05 prerunner.

 

While you are braking? You could be describing axle wrap, but that's usually felt as you take off from a stop more.

 

And do you feel pulsating on the brake pedal? Maybe a better explanation of what you mean by jumps a bit.

 

Not a pulsation , its hard to describe but when you let off the peddle you feel a little thump in the back end.And what is axle wrap and is it serious.

 

I keep reading about "axle wrap" and would also like to know what it is.

 

Axle wrap is partly the result of our weaker springs, which Tacomas are notorious for having unfortunately but, I copy and pasted this from another site to save myself all the typing... :


Axle wrap is a condition that affects vehicles equipped with leaf-type springs under extreme acceleration and, occasionally, deceleration. When the driver of a leaf spring-equipped vehicle applies excessive throttle, the rear axle housing attempts to rotate around the axles as the tires grip the road's surface. The rotation of the axle housing is defined as axle wrap. Under high-traction conditions, the leaf springs will bend as the axle housing rotates around the axle; this bending or wrapping of the springs lends to the term, axle wrap.

 

Or it could just be the ac condensor kicking on.

Eitther way not a big deal.

 

I don't believe that is at all what the OP is describing. But agree, axle wrap is not a big deal.

 

I notice it on mine more, when the A/C is on, but it has never bothered me.

 

Axle wrap. When you brake the axle housing tries to rotate and twists the leaf springs a bit. This energy is stored and the spring. When you let off the brake peddle this energy is released causing the thump.

Check the leaf spring u bolts and make sure they are torqued upwards of 75 ft lbs or so. If they are your springs may be just getting weak. Nothing to really worry about. I felt it in my 2012 AC, but after I upped the torque on the axle u bolts it went away. I think it is more pronounced on the double cab models.

 

It's most likely axle wrap. No biggie. Mildly annoying for sure. Usually takes a few bucks to fix it. New leafs would be your best bet.

 

to everyone saying 'axle wrap' I doubt it...though this might be true in some cases...

as long as there is no problem with the propellor, because there is a TSB for 2wd
T-SB-0250-12: '05-'12 Tacoma: 2WD Rear Propeller Shaft (Driveshaft) Clunk/Thunk Noise


a few facts about Toyota automatic transmission I have seen on my 4runner
and tacoma. Note the 4runner has IRS, no leafs and no axle wrap is possible.

When coming to a stop, and stopping and holding the brake, the internal transmission brakes and clutches pause for a moment before changing to 1st, and this causes an occasional bump-from-behind feeling. My 4runner has done this once in a while, my new Tacoma does this once in a while. It think is normal for Toyota and the way the tranny ecu is set up. since the feeling is identical and the suspension is different...this is why I suggest it is not axle wrap, and normal. ymmv

 

Yup, I experience the same thing. Was never sure what is was till now.

 

I've heard that low transmission fluid can cause these symptoms...

 

Happens to me too in my new 2014 DCSB. First time it happened I thought the car behind me gave me a light tap.

 

Could be the brake shoes sticking

 

I agree that some have had this issue, and also some have had the issue with the a/c compressor kicking on and jumping forward.

But what the OP is describing sounds exactly like axle wrap. He didn't say he's at any point he is "jumping forward".

 

Thanks for the answer Deevon. I wondered why AAL or new springs were often offered as a solution to this problem.