Strange jump from when I stop at a stop sign

Most of the time when I stop at any stop sign I get a strange jump after I press the brake pedal. I had my truck for about a month. I talked to my mechanic and he said that it could be that the shocks need replacement but that's without checking it. It does have 113xxx miles and it looks like the shocks seemed to be The stock ones. What do you guys think?

 

It's the air conditioner.

 

How?

 

Looks like you edited your OP, which sounds similar but like a different problem than the "surge" at a stoplight that is so commonly reported here.

 

Is it bouncing as you press the pedal? Or as you come to a stop?

 

Mine does it too...first time it happened I thought I got "Boy Georged" (you know -- slammed in the rear) but then I realized that it happens from time-to-time. I'm not sure what it is but you get used to it...

 

I have read its everything from axle wrap to hard shifting into 1st gear. My truck used to do it until I went with a SUA setup. That makes me think it was axle wrap. OP do you notice it more when you come to abrupt stop? Like the harder you stop the more you feel it thump?

 

As I come to the stop

 

Yea. I do. That's when I feel it the most.

 

i thought it was the slip yoke on our driveshafts?

 

I still have a slip yoke and it doesnt do it anymore. The only thing I changed was leaf springs to an SUA setup. The other thing you can do is when you come to a hard stop keep the pedal depressed really hard, you wont feel the thump until you release the pedal. Thats because your rear brakes are holding the axle wrapped and when you release it thumps. This is also why it doesnt do it on soft stops, your rear brakes dont hold hard enough to hold the axle

 

Thanx guys. Now I have a better idea of what to do.

 

I guess I've never noticed mine then

 

Weird, you should make a thread about it

 

You really think so???

 

i had a weird stop once. truck also didn't take off from being parked very well on occassion. come to find out I think my local tire shop (trying not to point fingers) when I asked them to check my drum brake shoes the kids knocked some of my drum brake springs loose or something. they put in a new spring kit and i was good to go