Still having Brake problems with P32 chassis

[Grandave]

The auto park brake system you helped me with seems to be OK at this time.

While we were having issues with the parking / auto brake, I took the opportunity to have the main brakes checked as there seemed
to have excessive pedal travel.
The litany of events follows!
1) Discs were skimmed.
After lines were bled I drove the unit and found the front brakes were getting hot.
2) Calipers replaced with new.
Brakes still were getting hot.

3) Master cylinder replaced with new and Hydra Boost expert rebuilt with a year warranty.
Calipers still not freeing properly.

4) At great expense replaced all the brake lines!.
Calipers still not freeing!

Today ordered new spacer to replace existing, between Hydra boost and master cylinder.

Can you suggest how to proceed, is there a special adjustment needed when new spacer is installed?
Workhorse say the spacer is critical to calipers opening after brakes applied?

We wish to take this unit up to Canada to visit friends, but need to have sound brakes that do not overheat!

I have been blessed to have many vehicles during my 77 years, but not since my (1950 ish) Fiat Topolino 500cc have I
had one with more challenges than the P32 chassis on this otherwise excellent Airstream motor home!!
Every Blessing

[DaveFL]

Everybody here talks about the p30 Chevy chassis but yours should be a Workhorse chassis as chevy in their wisdom sold out to them. Along with the problems, but I haven't run across where there was a recall when there should have been a recall, on the auto brake and the caliper system brakes.
Chevy took the simple hand brake and replaced with electro-mechanical high tech(POS), instead of modifying the transmission by adding a sturdier prawn to hold in park. The caliper brakes on mine suffered from overheat in rear due to crud in the fluid, water boils off and steam doesn't compress the same as brake fluid, but my feeling is that the slide mechanism on the calipers gets rusty and freezes up. When your mechanic replaced the calipers and turned the rotors, did he do a through job of cleaning up and testing their release as well as their application? I found an IR thermometer can aim and check exactly where the hottest spot is around the wheel and axle.

[Colin4]

Originally Posted by DaveFL

Everybody here talks about the p30 Chevy chassis but yours should be a Workhorse chassis as chevy in their wisdom sold out to them. Along with the problems, but I haven't run across where there was a recall when there should have been a recall, on the auto brake and the caliper system brakes.
Chevy took the simple hand brake and replaced with electro-mechanical high tech(POS), instead of modifying the transmission by adding a sturdier prawn to hold in park. The caliper brakes on mine suffered from overheat in rear due to crud in the fluid, water boils off and steam doesn't compress the same as brake fluid, but my feeling is that the slide mechanism on the calipers gets rusty and freezes up. When your mechanic replaced the calipers and turned the rotors, did he do a through job of cleaning up and testing their release as well as their application? I found an IR thermometer can aim and check exactly where the hottest spot is around the wheel and axle.

Sorry but off topic from the original post.....But...Hahah POS park brake is right! Decided to get my RV out of storage to go camping. The park brake would NOT release!~! I almost called all our friends to cancel. Thank goodness I had my voltmeter and tools with me and decided to check a few things. 4 hours later I found a damaged $12 bleeding relay. Replaced both sensors for good measure too. Ordered replacements. Replaced 3 faulty leaking sensors in 5 years. I cant understand the logic of this system going through the schematics it seems like an accident waiting to happen and so many things can go wrong which will leave one stranded.. Craziness. Anyway I remembered a few months back the Rotten green switch failed while I was on the highway. I could not immediately stop so drove a while with the hydraulic pump running. What must have happened was the run relay got too hot and caused damage to the contacts. Now I keep a spare relay too.

[Colin4]

Originally Posted by Grandave

The auto park brake system you helped me with seems to be OK at this time.

While we were having issues with the parking / auto brake, I took the opportunity to have the main brakes checked as there seemed
to have excessive pedal travel.
The litany of events follows!
1) Discs were skimmed.
After lines were bled I drove the unit and found the front brakes were getting hot.
2) Calipers replaced with new.
Brakes still were getting hot.

3) Master cylinder replaced with new and Hydra Boost expert rebuilt with a year warranty.
Calipers still not freeing properly.

4) At great expense replaced all the brake lines!.
Calipers still not freeing!

Today ordered new spacer to replace existing, between Hydra boost and master cylinder.

Can you suggest how to proceed, is there a special adjustment needed when new spacer is installed?
Workhorse say the spacer is critical to calipers opening after brakes applied?

We wish to take this unit up to Canada to visit friends, but need to have sound brakes that do not overheat!

I have been blessed to have many vehicles during my 77 years, but not since my (1950 ish) Fiat Topolino 500cc have I
had one with more challenges than the P32 chassis on this otherwise excellent Airstream motor home!!
Every Blessing

Can you let me know if you fixed your problem GranDave. My 2004 30 S.O Landyacht is having a similar issue. Just the front passenger wheel caliper will not release completely and will heat up. I haven't inspected it myself and I plan too. Just qualified Brake people have done troubleshooting. When we were in NC mountains it was a huge issue. I'm considering installing a retrofit temp system just so I can monitor the heat while in motion.
Thanks.

[PeterH-350LE]

Originally Posted by Grandave

The auto park brake system you helped me with seems to be OK at this time.

While we were having issues with the parking / auto brake, I took the opportunity to have the main brakes checked as there seemed
to have excessive pedal travel.
The litany of events follows!
1) Discs were skimmed.
After lines were bled I drove the unit and found the front brakes were getting hot.
2) Calipers replaced with new.
Brakes still were getting hot.

3) Master cylinder replaced with new and Hydra Boost expert rebuilt with a year warranty.
Calipers still not freeing properly.

4) At great expense replaced all the brake lines!.
Calipers still not freeing!

Today ordered new spacer to replace existing, between Hydra boost and master cylinder.

Can you suggest how to proceed, is there a special adjustment needed when new spacer is installed?
Workhorse say the spacer is critical to calipers opening after brakes applied?

We wish to take this unit up to Canada to visit friends, but need to have sound brakes that do not overheat!

I have been blessed to have many vehicles during my 77 years, but not since my (1950 ish) Fiat Topolino 500cc have I
had one with more challenges than the P32 chassis on this otherwise excellent Airstream motor home!!
Every Blessing

I feel your pain, because my first car was a 1962 white Fiat 500
Interesting suggestion to install spacers, since I did that on a 1987 P30 Classic Airstream. My brakes completely locked up, fortunately in my driveway. Since I already had a fair warning that this vehicle may have that problem (pre-loading of the brake system) I had a buddy sit close to one of the wheels and slowly unbolted the Master cylinder, a quarter turn at a time. When we heard the calipers releasing, I measured the space with a feeler gauge and used spacer of that size, I thought at the time, it was a rather unprofessional way to fix my problem, that is why I am surprised to hear it from the pros. Just please don't take my word for it.
Good luck!

[JimClark]

Originally Posted by Grandave

The auto park brake system you helped me with seems to be OK at this time.

While we were having issues with the parking / auto brake, I took the opportunity to have the main brakes checked as there seemed
to have excessive pedal travel.
The litany of events follows!
1) Discs were skimmed.
After lines were bled I drove the unit and found the front brakes were getting hot.
2) Calipers replaced with new.
Brakes still were getting hot.

3) Master cylinder replaced with new and Hydra Boost expert rebuilt with a year warranty.
Calipers still not freeing properly.

4) At great expense replaced all the brake lines!.
Calipers still not freeing!

Today ordered new spacer to replace existing, between Hydra boost and master cylinder.

Can you suggest how to proceed, is there a special adjustment needed when new spacer is installed?
Workhorse say the spacer is critical to calipers opening after brakes applied?

We wish to take this unit up to Canada to visit friends, but need to have sound brakes that do not overheat!

I have been blessed to have many vehicles during my 77 years, but not since my (1950 ish) Fiat Topolino 500cc have I
had one with more challenges than the P32 chassis on this otherwise excellent Airstream motor home!!
Every Blessing

We are entering this same arena with same problems. Did you find solution(s)?


Thank you. --Jim --2002 8.1L workhorse 40,000 miles.

[92landyacht]

On my 1992 P30 LY I found one of the rubber hoses was deteriorating and caused the road side front caliper to lock up. Replaced all of the rubber lines and all is well. Very common problem for any hydraulic brake system using rubber lines at the wheels.

[schmaco]

Hello,
I had a ford expedition that had front disk brakes that exhibited Delayed Release and finally Drag that was caused by the Rusted Support Bracket squeezing the soft brake hose thus causing restriction. The rust corrosion swelled.

Stephen

[GCinSC2]

Sorry, not a motor home owner but maybe a basic question.

In general when a DIY or tech does a disc brake pad replacement the caliper must be compressed to allow the new thicker pads to be installed.

Have you tried removing a caliper and trying to compress the piston(s)? Piston should compress with a little force, c-clamp or piston tool and this moved the piston IN and the fluid UP back to the reservoir.

Piston doesn't compress? Now research that one and if I'm following this right testing by loosening the master cylinder and creating a small gap. This would allow the master cylinder piston to return to home position, ports open, pressure released.

Good luck and this is an arm chair suggestion.

Gary

[JimClark]

Thanks for your replies!

I am planning to replace all calipers and discs.
Hydraboost is bad, so replacing that too. No ABS light or codes, so hopefully operable.

Had not thought about flex lines to calipers. Will look to get those too.

Our auto park of course is long dead. Using chocks...

Sure wish it was a Ford chassis. (Or even Fiat!��)

.

[PeterH-350LE]

Originally Posted by JimClark

Thanks for your replies!

I am planning to replace all calipers and discs.
Hydraboost is bad, so replacing that too. No ABS light or codes, so hopefully operable.

Had not thought about flex lines to calipers. Will look to get those too.

Our auto park of course is long dead. Using chocks...

Sure wish it was a Ford chassis. (Or even Fiat!��)

.

You have 5 flex lines best to replace. My 350 auto park brake feature is long gone too. When had a custom heavy duty 4l80e built, I made sure it had a parking pawl.

[TerraYacht]

Thanks for various info, will check my rubber hoses. The aftermarket for my cars offers Teflon lines with steel braid to eliminate the rubber swelling and soft pedal issues but I don't have anyone who makes those on a custom basis.

My TerraYacht had a brake issue on a ~25 mile run with one hill climb descent and it was pulling strongly to the left, over a quarter turn of the steering wheel. When I got home I measured about 270 deg.F on the right front disk and over 500 deg on the left!

Drove back to my repair shop and had them replace the discs and calipers and, of course, all new brake fluid.

I used to do all that kind of work myself on my other vehicles but did not have the incentive (or weight-lifting capability) to pull these 19.5" wheels.

[JimClark]

Originally Posted by TerraYacht

Thanks for various info, will check my rubber hoses. The aftermarket for my cars offers Teflon lines with steel braid to eliminate the rubber swelling and soft pedal issues but I don't have anyone who makes those on a custom basis.

My TerraYacht had a brake issue on a ~25 mile run with one hill climb descent and it was pulling strongly to the left, over a quarter turn of the steering wheel. When I got home I measured about 270 deg.F on the right front disk and over 500 deg on the left!

Drove back to my repair shop and had them replace the discs and calipers and, of course, all new brake fluid.

I used to do all that kind of work myself on my other vehicles but did not have the incentive (or weight-lifting capability) to pull these 19.5" wheels.

I am with you on that. A friend with more capable tools has offered to work with me.... we’ll see how it goes over the next few weeks. Still gathering parts.

[GCinSC2]

I pondered this a bit and might have a simpler diagnostic for a system that is holding pressure in the system.

Ask if there should be any pressure in this system when your foot is OFF of the brake pedal? No, ok I'm with you.

To do a quicker test, crack a bleed screw. Fluid sprays out or a slight drip?

My noggin says sprays out = some pressure in the system.

[schmaco]

Hello,
Another piece of my past.


i figured out that the Calipers on my 2004 Chev Silverado were sticking because the two pins and their sockets were rusted preventing Sliding.
Cast Metal Socket with the pins Huh.
Good Luck to us all.
Stephen