Brakes brakes brakes

[JeOsbolt]

04.5 2500 4 new rotors, new master cylinder from ray bestow, new booster, new front rubber lines, fluid flush.
Brakes dragging I’ve replace the above even new calipers and problems went away for a couple months, they are back again pulled up at home used temp gun and checked all 4 rotors 200degrees after light brake use.
Seems that my front passenger starts to drag first and the truck will pull to the right and intermittently wonder left and kinda follow the road, going over rough spots on the interstate @ 70mph feels extra sensitive on front passenger. when I start the truck every morning to go to work the rpm’s drop a few hundred and come right back to 750rpms and first few initial turns of the steering wheel I can hear the power steering whine. I’m at a loss.
this issue is about to cost me a engine. It’s loading the engine up so bad me egts easily hit 1200+ going up a slight hill at 60mph with no trailer, nothing in the bed, empty.
I’ve noticed recently my egts at idle have crept up to 500 from the normal 370ish. In drive at idle holding the brake it’s 600. As soon as start uphill highway speeds it feels like the turbo has locked up and just lugs down I have to pretty much mash the pedal 2 or 3 times to get it wound back up to get to the top of hill. ‍
30% over flux sac injectors, 67/67 drop in turbo, Fummins tuning with hp tuners, gdp spin on fuel filter kit, new 10mm cp3, new mprop, valves adjusted, new fuel filters , clean air filter, new throttle pos sensor, new map sensor, new crank sensor, etc

 

[Darkbloodmon]

Are all the friction and contact points on the calipers sliding as they should? If so I'd revisit the bleeding procedure. The hydro may also be pressurising the system without brake pedal input. I forget the term for the cylinder mounted to it, but to my knowledge they're colored and represent different specifications based off their color, For instance a hydro from a Duramax can swap over but they may not be using the same system specifications. All this to say; verify you have the right hydro for your application and that its functioning correctly from memory some hydro's physically cross over from different vehicle applications.

Its hard to pinpoint when theres alot of parts being replaced on the same system. I keep a log book of my truck for everything and I avoid doing mass replacements just so I can go back to my notes and previous observations prior to the work I did to compare and isolate issues.

 

[Yo Hoot]

Might be track bar. When it's loose truck lurches sideways when hard braking.

 

[petersonj]

04.5 2500 4 new rotors, new master cylinder from ray bestow, new booster, new front rubber lines, fluid flush.
Brakes dragging

Did you perform the repairs, or did a shop perform the repairs?

I would suspect an incorrect push rod length (too long) between the brake booster and the master cylinder. If the master cylinder is engaged (even by only 1/8") when the brake booster and the master cylinder are fastened together, the compensating ports in the master cylinder will be covered. This condition will not allow for brake fluid to return to the master cylinder. There must be some free play in the push rod after the components are assembled.

The symptoms won't necessarily show up right away because the temperature of the brake fluid needs to rise. When the brake fluid temperature does rise, the brake fluid expands, but the fluid cannot return to the reservoir, consequently the caliper pistons start to apply the brakes. The temperature rise of the brake fluid can be caused by ambient temperature increasing or a few applications of the brakes, or both. The symptoms can go away when the brake fluid cools.

I think that you could check for this situation by loosening the master cylinder to brake booster fasteners. Watch for the master cylinder trying to push itself away from the booster without your assistance. If this occurs, then the push rod is too long.

When I replaced both the brake booster and master cylinder (both new) on my truck last summer, the provided push rod was 5 mm too long. I had to shorten it to the proper length.

- John

 

[Ozymandias]

Also a just slightly restricted return line from the hydroboost can give the same symptoms.
Mine did it by just adding a filter to the return.

 

[Topzide]

Just adding, when new calipers were installed, were the slide pins lubricated? This little thing can cause the calipers to be dragging. This is why I clean and lube them every year with my annual maintenances'. Have found them to not be sliding well, even in just a year. Have had several calipers have slide pins seized, to where I had to replace the caliper. Different vehicles though, once on the 3500, right after I got it. Hence the annual checking of components!

 

[sag2]

Put a washer or two between the booster and the master cylinder. If it clears up the pushrod is too long.

 

[JeOsbolt]

Did you perform the repairs, or did a shop perform the repairs?

I would suspect an incorrect push rod length (too long) between the brake booster and the master cylinder. If the master cylinder is engaged (even by only 1/8") when the brake booster and the master cylinder are fastened together, the compensating ports in the master cylinder will be covered. This condition will not allow for brake fluid to return to the master cylinder. There must be some free play in the push rod after the components are assembled.

The symptoms won't necessarily show up right away because the temperature of the brake fluid needs to rise. When the brake fluid temperature does rise, the brake fluid expands, but the fluid cannot return to the reservoir, consequently the caliper pistons start to apply the brakes. The temperature rise of the brake fluid can be caused by ambient temperature increasing or a few applications of the brakes, or both. The symptoms can go away when the brake fluid cools.

I think that you could check for this situation by loosening the master cylinder to brake booster fasteners. Watch for the master cylinder trying to push itself away from the booster without your assistance. If this occurs, then the push rod is too long.

When I replaced both the brake booster and master cylinder (both new) on my truck last summer, the provided push rod was 5 mm too long. I had to shorten it to the proper length.

- John

I do all my own repairs, pedal rod has about 1/4 inch up and of travel I prob should double check it

 

[JeOsbolt]

Did you perform the repairs, or did a shop perform the repairs?

I would suspect an incorrect push rod length (too long) between the brake booster and the master cylinder. If the master cylinder is engaged (even by only 1/8") when the brake booster and the master cylinder are fastened together, the compensating ports in the master cylinder will be covered. This condition will not allow for brake fluid to return to the master cylinder. There must be some free play in the push rod after the components are assembled.

The symptoms won't necessarily show up right away because the temperature of the brake fluid needs to rise. When the brake fluid temperature does rise, the brake fluid expands, but the fluid cannot return to the reservoir, consequently the caliper pistons start to apply the brakes. The temperature rise of the brake fluid can be caused by ambient temperature increasing or a few applications of the brakes, or both. The symptoms can go away when the brake fluid cools.

I think that you could check for this situation by loosening the master cylinder to brake booster fasteners. Watch for the master cylinder trying to push itself away from the booster without your assistance. If this occurs, then the push rod is too long.

When I replaced both the brake booster and master cylinder (both new) on my truck last summer, the provided push rod was 5 mm too long. I had to shorten it to the proper length.

- John

Also sometimes it sits over night and cools and the issue is still there in the am. Not every time but it has happened and it was doing the same thing with original booster and master cylinder

 

[JeOsbolt]

Just adding, when new calipers were installed, were the slide pins lubricated? This little thing can cause the calipers to be dragging. This is why I clean and lube them every year with my annual maintenances'. Have found them to not be sliding well, even in just a year. Have had several calipers have slide pins seized, to where I had to replace the caliper. Different vehicles though, once on the 3500, right after I got it. Hence the annual checking of components!

Yes they were greased but I haven’t done it in awhile I put the new calipers on not quite a year ago and I’ve only put maybe 2500 miles on it truck has been in my shop for other repairs such as transfer case, new oil cooler, and sent my injectors off to be checked ended up with contaminated fuel from cp3 eating itself so I had to drop tank and do the whole fuel system cleanup

 

[JeOsbolt]

Also a just slightly restricted return line from the hydroboost can give the same symptoms.
Mine did it by just adding a filter to the return.

I haven’t thought of that although I did flush lines out when I put the new power steering pump on

 

[JeOsbolt]

Might be track bar. When it's loose truck lurches sideways when hard braking.

I’ve suspected that but it I’ll when I’m not touching the brakes and I’m on the accelerator

 

[JeOsbolt]

Are all the friction and contact points on the calipers sliding as they should? If so I'd revisit the bleeding procedure. The hydro may also be pressurising the system without brake pedal input. I forget the term for the cylinder mounted to it, but to my knowledge they're colored and represent different specifications based off their color, For instance a hydro from a Duramax can swap over but they may not be using the same system specifications. All this to say; verify you have the right hydro for your application and that its functioning correctly from memory some hydro's physically cross over from different vehicle applications.

Its hard to pinpoint when theres alot of parts being replaced on the same system. I keep a log book of my truck for everything and I avoid doing mass replacements just so I can go back to my notes and previous observations prior to the work I did to compare and isolate issues.

Accumulator is the term and yes it matched the original one I removed I still have the old master cylinder and hydraboost to use for reference, I did notice some brownish gunk in the master cylinder Tao I replaced it as well bf flushed the lines with brake clean for several hours then flushed again with cheap brake fluid the bled the system with some quality fluid