I broke an axle and caliper so I picked up a new rear end. Disc brakes with single piston caliper. I swapped the rear end in and used the calipers from that, along with new rotors and pads. The pistons pushed in easily and everything went together great. The brakes are awesome, way better then they have ever been. I swapped to 4.10s as well.

I noticed it was harder to get moving from a stop the other day. The rear brakes were smoking so im figuring they are dragging and I cant figure out why. I do have an ABS light on after all of this, but no idea where thats from. All connections in front are tight, bled all 4 brakes etc. I never unhooked the brake lines from the truck, just removed the rear end and put new calipers on so loss of fluid was minimal.

Any ideas on what to check/try? Could both calipers be bad from the rear end I swapped in? They were super clean, no rust or dirt in them, and pistons moved easily back in. New brake hardware. Tried bleeding the ABS module on a dirt road and that did not turn off the ABS light.

 

Those single piston rear calipers are known to go bad. Try taking a caliper back off and pushing the piston in, it likely won't move as easy.

My buddys truck with only 73k miles on his needed new calipers.

 

Thats what im thinking. It sat at the junkyard for 2 years, so anything could have happened to them. God damn "New" calipers I bought for the truck last year have smaller bracket holes and holes on the caliper, so I had to use the OEM bracket and caliper, couldnt mix my caliper with the OEM bracket. Go figure. Ill track some down. was going to crack the bleeder and let some fluid out just to see if I could free them up at all and see if they would grab again.

 

If they sat in the yard with the pistons extended out, the pistons could have acquired some corrosion or contaminant that are inhibiting them from popping back out after being pushed in for the new pads. You can try popping them out and cleaning them to see if they move freely. However, I tried to rebuild the single piston brakes that stuck on my 2000 but could not get the piston back in as the caliper bore was warped. The calipers had been ground for wheel fitment though.

Also, are you using the original stock rubber flex lines? With age, they have been know to deteriorate and not allow fluid flow back out of the caliper.

 

you went from drum to disc in rear?

you will need a new proportional valve for rear disc....

 

My truck came with disc in the rear. I only swaped rear ends due to breaking the stock one.

The entire brake system, from front to rear is brand new. New lines, pads, calipers, rotors, hoses etc. I replaced all of that about a year ago.

The calipers had like new pads in them, so they wernt extended very far. I was able to push them back in easily.

Im starting to think its something with my ABS. My abs light is on and it was not before i broke the rear end and caliper (slid into a curb). I touched my front rotors today and they were as hot as the rears. I pulled the ABS fuse but that made no difference. Not really sure where to go.

 

Well still havent really figured it out. Found out that i was getting the ABS code from the right front sensor, so I swapped that out and still getting a code. going to have to check the rest of the wiring.

I jacked the truck up and put it in gear, the rear spun with no throttle, forward and reverse. Brakes worked fine and wheels started spinning right away when I let off. Not sure why it still feels like they are grabbing.

 

If either one of your front wheel hubs has excess bearing play, then that will trigger an ABS sensor failure. If that is the case, replacing just the sensor won't fix the issue. You'll just need to replace the entire wheel hub assembly. The new hubs usually come with sensors though.

Having taller/shorter than stock tires can also trigger the ABS. Does the light come on immediately or does it only happen after you've reached highway speeds?

Mike

 

Well i figured out the brakes. I had reused the calipers from the new rear end i picked up. Threw 2 new calipers on and all is well. Truck is a whole new animal with the 4.10s and no dragging brakes, even though its a small change.

For the ABS, I redid the whole truck a year ago. I swapped Moog hubs onto it then. The sensors that you can buy, are too long for the Moog hubs. I pulled the new sensor off tonight, the tip was broken off and the hub is full of the copper winding that is inside the sensor. The sensor is 1/8" longer than the sensor the Moogs come with. So I have a new hub on the way. Sucks but not much I can do. Hopefully that fixes it.

Im wondering if the fact that I have 4.10s in the rear now and im tuned for 3.73s has something to do with it? I didnt have an ABS light before I broke the axle. I have a retune on the way as well.

 

That's way your ABS light is on for sure then, get it tuned for 4.10's and right tire size it should go off.. as long as no other issues... If I swap to my drag radials a 28' tire from my daily tires 29.5' and keep the fronts which is 28' inch without adjusting the tune for it, it throws the ABS light.. It's constantly monitoring and comparing wheel speeds so its just freaking out because the trans rev/mile is out of whack in the tune.