Hyper sensitive brakes on 04.5 Ram 2500 quad cab long bed

[VFabricius]

I went to test the truck brakes on gravel and as I stopped at 1st intersection. I lightly tap the brakes and the front right wheel, locked and skidded, leaving about a 32 inch skid mark but none of the other wheels locked up. What confused me is that with that right front locking up caused a major shudder, which seemed like the other three wheels were locking up. I jacked up the right front wheel and found the pads which I installed new last July ‘22 we’re fine and when I started to loosen up the caliper, the whole caliper pivoted up and I noticed the bottom bolt was missing from the caliper bracket as shown in the picture. This is not the 2-12mm bolts that hold the caliper to the bracket but it’s the two 18 mm bolts that hold the bracket to the knuckle (if I’ve got the correct terminology).

 

[VFabricius]

You’ll notice I loosened the 2-12mm caliper bolts to pivot the caliper out to check pad thickness. They looked new. What happened was when I applied brakes, the caliper pivoted off the top bolt and it ground into the soft aluminum of the wheel causing the violent shudder throughout the suspension making me think all brakes were locking. Luckily this happened a mile from home and was able to brake downshifting or use emergency brake. We experienced the same problem dropping a top bolt on the driver’s side last year but it was a top bolt and caliper didn’t pivot from the bottom like this one. My mechanic son said never had to Locktite other caliper brackets before but we will these. Thanks everyone for your input trying to solve this problem.

 

[Rowdy Dalton]

Well, it looks like you have your answer, to your problem. I'm just surprised you didn't hear the scraping of the caliper against the wheel.

 

[Ozymandias]

When you are there, exchange the sliding pin assembly too. Yours are gone a long time ago.
They need to be sealed and lubed, you get them at every parts store for 5$ each side, bolt, slide, boot 2x.

 

[Ozymandias]

No loctite needed at these bolts but the proper torque from the FSM - torque is much higher then you'd think.

 

[petersonj]

when I started to loosen up the caliper, the whole caliper pivoted up and I noticed the bottom bolt was missing from the caliper bracket as shown in the picture.

We experienced the same problem dropping a top bolt on the driver’s side last year but it was a top bolt and caliper didn’t pivot from the bottom like this one.

There is a red flag here. Caliper mounting bolts do not come loose and fall out. Adding Loctite to a fastener is usually a bandaid. This has happened to you twice. I recommend rechecking torque on all fasteners for any brake work you have done on this truck.

Mounting surfaces need to be clean and flat. The fastener and the threads of the part being fastened must be clean. The fastener may or may not need to be lubed (check FSM). Correct torque is a must. With the correct torque, the fastener will stretch to an engineered length and this stretch is what will maintain its clamping force, even with vibration and thermal expansion / contraction present. Proper stretch is what makes the fastener stay tight, not Loctite.

- John

 

[Signal73]

Wow, thanks for the follow up.

 

[BarryG]

That happened to me quite a few years ago in my 01. Out in the middle of bfe. Went to hit the brakes and this awful grinding noise started. Got out to see what was up. Didn’t notice anything at first but then noticed the caliper hanging low in the wheel. Top caliper bolt fell out within the last 5 or 6 miles since my previous stop. Tried looking for the bolt on the road. It is amazing how many bolts are on the side of the road. This was like 415 pm closest town with any type of store was 30 miles away. Pulled into it 5 minutes before it closed. Dang if Napa didn’t have one he said you are lucky have sold 3 this week and had one left. Went out to parking lot took off tire put in bolt drove it another 50k without issue.

 

[Rowdy Dalton]

That happened to me quite a few years ago in my 01. Out in the middle of bfe. Went to hit the brakes and this awful grinding noise started. Got out to see what was up. Didn’t notice anything at first but then noticed the caliper hanging low in the wheel. Top caliper bolt fell out within the last 5 or 6 miles since my previous stop. Tried looking for the bolt on the road. It is amazing how many bolts are on the side of the road. This was like 415 pm closest town with any type of store was 30 miles away. Pulled into it 5 minutes before it closed. Dang if Napa didn’t have one he said you are lucky have sold 3 this week and had one left. Went out to parking lot took off tire put in bolt drove it another 50k without issue.

Did the NAPA happen to say that they just found that one on the side.of the road??

 

[sag2]

All sliding caliper bolts and caliper to knuckle bolts have thread locker from the factory. We use blue loctite on every brake and suspension fastener at the college and every fastener is torqued to OEM specifications. We do 3-4 brake jobs a day and it is amazing of all the different fastener sizes and torque specifications on the cars.

 

[VFabricius]

I was 1/2 mile from home when I experienced the brake lock issue and I typically try to anticipate a stop light and slow to a stop without breaking and was barely rolling at 10 mph so truck stopped in less than 3’ so I never really heard any scrapping, it was a lockup/shudder is all I heard. Went less than 20 mph for last half mile. I’ve already picked up new 12mm caliper slide bolts and rubber covers along with 18 mm bolt. Just need to get FSM recommendation for torque setting. Not gonna be easy to torque as I’m on jacks with limited swing of torque wrench but will get it right. Thanks again. I’m thinking I’ll check and relube and replace rubber slide bolt covers every 2 years now that I’ve seen what happened to the new ones I had on there from new rotors and pads installation

 

[MGreer]

250 ft/lbs for heavy duty trucks, 130 ft/lbs for light duty trucks (1500's)