Brakes on Truck?

[double bogey]

If i remember correctly the wobble is due to a warped rotor. The warping my be why they need to replace. Follow Longstrides advice above.

[Lutenbacher]

What type of truck is it?

[whitecrow]

Lots of stuff factors in on brake life...driving habits, weight of truck, how much towing, does your wife drive it, etc.
Just for comparison's sake, I drive a 2014 Ram 1500 with 120k+ still on the original pads/rotors. Tow boats/racecar trailers lots of weekends.
If you're eating up rotors/pads every 30k you need better parts, better mechanic, or have an issue with calipers or something.

[WS_AG]

How hard do you drive?

[RifleBowPistol]

24,000 miles on the front of a truck is a bit early for a brake job, but 24,000 miles on the rear of any vehicle, more so a truck is way early for a brake job.

Now you say you have a wobble you think is coming from the rear, I assume you mean, when braking you have some form of shaking going on, or brake shudder? A brake shudder problem on the other hand can happen at just about any point after a brake job is done. The quality of the brake rotors and pads do play some into how long it will go before you might get a shudder. But there are some vehicles, such as Ford Superdutys that can acquire a brake shudder inside of 5,000 miles of a brake job, commonly. I know I used to work at dealerships and I own a Superduty.
But with only 24,000 miles since the last brake job on the vehicle, if they replaced the rear rotors, even if you have a rear brake shudder, you should not need new rear rotors, in that low of mileage. They should have plenty of material to turn them.

Most vehicles, will wear the front brakes out two or three times before the rear wear out. There is typically 70% of the braking done by the front brakes. I usually see the fronts get three brake jobs to one rear brake job. But with trucks it can be more like two fronts to one rear brake job. With rotor warpage, like I said, it can happen quickly.

I know driving through water, when the brake rotors are hot, can warp them, I have been told that improper torque on the wheels can cause the rotors to warp. Why some vehicles have so much more rotor warpage than others, I don't know. I would sure love to know why my Superduty warps rotors so quickly. I have never come close to wearing out a set of pads on my truck, front or rear, the rotors warp long before the pads have any wear on them. So my truck gets a brake job typically when the pads still have 80% to 90% of the pad left.

I would look on your receipt from when they did the last brake job and see if they replaced the rear rotors or had them turned. If they were turned, possibly they are too thin to turn again, being warped now. If they installed new rotors, they should be able to be turned, by turning them, they may wind up near minimum thickness or noticeably thinner than new rotors, meaning less metal and likely to warp even quicker. Even though they still above minimum thickness. I know years ago, in the dealer, we found turning rotors on Superdutys was a waste of time, they would come back in even quicker after we turned the rotors.

Other reasons the rotors could be warped, would be the calipers sticking, which could be a caliper problem, caliper pin problem, caliper bracket problem or brake hose, that has collapsed inside. Or someone riding the brake pedal often. Pulling heavy trailers with no trailer brakes, but that is illegal now days.

Typically 24,000 miles, the brake pads should not be worn out on either the front or rear, unless something is wrong.