Good Sam Club Open Roads Forum: Tow Vehicles: Front brakes
Open Roads Forum Already a member? Login here.   If not, Register Today!  |  Help

Newest  |  Active  |  Popular  |  RVing FAQ Forum Rules  |  Forum Posting Help and Support  |  Contact  

Search:   Advanced Search

Search only in Tow Vehicles

Open Roads Forum  >  Tow Vehicles

 > Front brakes

Reply to Topic  |  Subscribe  |  Print Topic  |  Post New Topic  | 
Page of 4  
Prev  |  Next
BurbMan

Indianapolis, IN

Senior Member

Joined: 09/20/2001

View Profile



Good Sam RV Club Member


Posted: 02/02/22 10:09am Link  |  Quote  |  Print  |  Notify Moderator

fj12ryder wrote:

Just curious, how does the proportioning valve know whether the truck is loaded or unloaded. Your explanation makes quite a bit of sense, just wondering about the proportioning valve.


Most trucks use one or more ride height sensors that measure the distance from the body to the frame (or axles) and provide that input to the BCM/PCM/ABS computers.

My 2001 2500 Suburban had 4, one at each corner, and that data drove ABS modulation, shock damping, and also throttle response. The 8.1 was drive-by-wire, and it never seemed any slower when it was loaded up, the reason was that the computer knew the truck was loaded and would give the motor more fuel even though I wasn't stepping on the pedal any harder.

BenK

SF BayArea

Senior Member

Joined: 04/18/2002

View Profile



Posted: 02/02/22 10:54am Link  |  Quote  |  Print  |  Notify Moderator

My thoughts...

Fronts not warm...blockage, air in the front lines, MC piston seal, proportioning valve, and hanging caliper are the main things to look for

Easiest and cheapest is to bleed both front lines

Then check if the caliper is hanging. These are single piston with an anvil on the other side of the rotor. That means they must 'center' themselves during any stop and after some friction material has worn off. The caliper slide pin assembly needs to be replaced and properly greased. With the correct grease (high temp, disc brake grease)

My DIY for greasing the slide pin tube (the side pin slides inside this tube), between the O-Rings is to put it together and NOT finish the 2nd O-ring and while the interior is still open, poke in my grease gun for a couple strokes of grease. Then finish with both O-Rings engaged.
[image]
[image]Click For Full-Size Image.

Some times, most times also put in some synthetic motor oil (Mobil 1) that has my own mixture of powdered Molybdium Disulfide with this modified oiler
[image]
[image]Click For Full-Size Image.

[image]
[image]Click For Full-Size Image.

Bleeding. Normally use the giant "C" clamp method. Lost the Internet posting link when Photobucket switched from freebie to for $$$ and will have to make up another, but have posted it here often. Or use gravity bleed. Be sure to include opening the ABS body valves to bleed them too...this will require a scan tool that can open & hold them open while bleeding

Proportioning splits the braking PSI/GPH between front and rear. It could be sticking and if replaces, must bleed all brake lines.

A very remote possibility is that your front caliper has a pebble/stone/etc wedged in there preventing movement. Have come across one a loooong time ago

Good luck and please report back on how it went


-Ben Picture of my rig
1996 GMC SLT Suburban 3/4 ton K3500/7.4L/4:1/+150Kmiles orig owner...
1980 Chevy Silverado C10/long bed/"BUILT" 5.7L/3:73/1 ton helper springs/+329Kmiles, bought it from dad...
1998 Mazda B2500 (1/2 ton) pickup, 2nd owner...
Praise Dyno Brake equiped and all have "nose bleed" braking!
Previous trucks/offroaders: 40's Jeep restored in mid 60's / 69 DuneBuggy (approx +1K lb: VW pan/200hpCorvair: eng, cam, dual carb'w velocity stacks'n 18" runners, 4spd transaxle) made myself from ground up / 1970 Toyota FJ40 / 1973 K5 Blazer (2dr Tahoe, 1 ton axles front/rear, +255K miles when sold it)...
Sold the boat (looking for another): Trophy with twin 150's...
51 cylinders in household, what's yours?...

Grit dog

Black Diamond, WA

Senior Member

Joined: 05/06/2013

View Profile


Offline
Posted: 02/02/22 11:10am Link  |  Quote  |  Print  |  Notify Moderator

What is a going on here??
Good golly, pump the brakes (lol) y’all.
OP never even said he has a brake problem. He just changed 4 sets of brake pads and either 1 or 2 rotors (unclear from his 1 relatively vague post).
While I don’t have a lot of faith that many could diagnose a brake problem and know how to repair it, which is what y’all’s great advice is trying to provide, I sort of believe that if the truck wasn’t stopping properly, even the least observant of people (not saying the oP is unobservant) would identify and state that the brakes weren’t working right, if they were looking for info or advice.


2016 Ram 2500, MotorOps.ca EFIlive tuned, 5” turbo back, 6" lift on 37s
2017 Heartland Torque T29 - Sold.
Couple of Arctic Fox TCs - Sold

BenK

SF BayArea

Senior Member

Joined: 04/18/2002

View Profile



Posted: 02/02/22 11:49am Link  |  Quote  |  Print  |  Notify Moderator

additional comments embedded in red below

snowpeke wrote:

I did a brake job on my 2002 2500 Dmax. The back brakes on the right rear were down to metal to metal. Put on a new rotor and pads. Now to the front.

There were a lot of pad left but changed them any way. Now for a test drive the back brakes were warm but the front were cold.

Says your fronts are not in the braking ball game *AND* will not bed in properly...if ever

As bedding in requires the friction material to get hot enough to out-gas, which then condenses onto the brake rotor surface. This is part of 'curing' the friction material, and advise that there are many Internet comments that today's friction material does NOT need to be cured...I say as long as there are binders in the friction material, it needs to be cured by high temp baking

Friction material on friction material is the best braking, as that has the highest coefficient of friction.

But do NOT stop while the friction material is out-gassing. That will bake on a thicker layer of friction material that will have future braking 'pulsate', as if the rotors are warped. To remove those higher friction material spots, get up to highway speed and NAIL the brakes. That will scrub off those high spots.

Then continue to roll to get an even condensed layer of friction material on the rotors.

No biggie to have a high spot baked on...just repeat the above highway scrub proceedure




How can I get them to work equally?

My previous response addresses your question and it might take an ASE Master Brake mechanic to diagnose & fix it

Note: am not an ASE certified brake person.

Just someone who has designed industrial disc brakes (most common were 17"-24" dia range) and the biggest one is a 48" dia disc and calipers (half calipers, as they only pressed onto the disc from one side & married with another one on the other side of the disc)




snowpeke

Nevada City California

Senior Member

Joined: 10/10/2004

View Profile



Good Sam RV Club Member


Posted: 02/02/22 02:26pm Link  |  Quote  |  Print  |  Notify Moderator

Thanks for the advice just took a one dayn RV trip and they stop the truck and trailer fine.


2002 Chevy DuraMax
2014 jayco eagle
Two Pekingese dogs

Grit dog

Black Diamond, WA

Senior Member

Joined: 05/06/2013

View Profile


Offline
Posted: 02/02/22 02:31pm Link  |  Quote  |  Print  |  Notify Moderator

snowpeke wrote:

Thanks for the advice just took a one dayn RV trip and they stop the truck and trailer fine.


ROFLMAO
[emoticon]

RoyJ

Vancouver, BC

Senior Member

Joined: 10/19/2006

View Profile


Offline
Posted: 02/02/22 03:33pm Link  |  Quote  |  Print  |  Notify Moderator

The front brakes more under HEAVY braking. The proportioning valve assumes enough weight transfer has occurred and send more hydraulic pressure forward. Under light braking, most modern trucks/cars use the rears more.

Now if the fronts are actually cold / lukewarm, there might be a problem.

Have you tried hard (threshold of ABS) braking and then carefully feel the front for increased heat?

Grit dog

Black Diamond, WA

Senior Member

Joined: 05/06/2013

View Profile


Offline
Posted: 02/02/22 04:52pm Link  |  Quote  |  Print  |  Notify Moderator

RoyJ wrote:

The front brakes more under HEAVY braking. The proportioning valve assumes enough weight transfer has occurred and send more hydraulic pressure forward. Under light braking, most modern trucks/cars use the rears more.

Now if the fronts are actually cold / lukewarm, there might be a problem.

Have you tried hard (threshold of ABS) braking and then carefully feel the front for increased heat?

scroll up 2 posts. OP said his brakes work fine.

time2roll

Southern California

Senior Member

Joined: 03/21/2005

View Profile



Good Sam RV Club Member


Posted: 02/02/22 07:38pm Link  |  Quote  |  Print  |  Notify Moderator

snowpeke wrote:

Thanks for the advice just took a one dayn RV trip and they stop the truck and trailer fine.
If the rears are wearing substantially faster than the front.... I believe the brakes are not working properly or were poorly designed.


2001 F150 SuperCrew
2006 Keystone Springdale 249FWBHLS
675w Solar pictures back up

wowens79

Georgia

Senior Member

Joined: 01/05/2015

View Profile


Offline
Posted: 02/03/22 06:52am Link  |  Quote  |  Print  |  Notify Moderator

The brakes on my 2002 Chevy HD wore really even, and a long freaking time. I replaced the original pads at 225,000 miles, and all 8 pads wore identically, you could tell no wear difference in any of them.
Best brake system I ever had.
My wife had an accord, that the back brakes wore faster than the front, but the rear pads were about half the size of the front ones.


2022 Ford F-350 7.3l
2002 Chevy Silverado 1500HD 6.0l 268k miles (retired)
2016 Heritage Glen 29BH
2003 Flagstaff 228D Pop Up

Reply to Topic  |  Subscribe  |  Print Topic  |  Post New Topic  | 
Page of 4  
Prev  |  Next

Open Roads Forum  >  Tow Vehicles

 > Front brakes
Search:   Advanced Search

Search only in Tow Vehicles


New posts No new posts
Closed, new posts Closed, no new posts
Moved, new posts Moved, no new posts

Adjust text size:




© 2022 CWI, Inc. © 2022 Good Sam Enterprises, LLC. All Rights Reserved.