When the brakes go out, going 90 mph

[alton]

Originally Posted by MinntoMich

I have owned many vehicles that I have never touched the brake fluid on. That being said I did just swap out a master cylinder on a 21 year old pickup and the brake fluid that came out of the bleeders did not look anything like. But then again that pickup is not a motorhome, at the top of a steep grade, and doesn't have thousands of pounds behind pushing it along. Your lucky. Not too make light of your experience but that would have been some interesting dash cam footage.

I was a kid fleet manager. We had a very strong P M program and until I purchased a motor home on a Work Hours chassis at less then 2 years old I began to have brake problems. I was told it was because I haven't changed the fluid. I am still not convinced that was the problem .

[Jchemie]

Glad you came out of that one alive. Scary ride! First thing I did when I bought an 11 year old used coach was replace all the fluids with Amsoil synthic oils. With 11 years & only 34K on it, it was cheap insurance. Brake fluid was very dark, test strip indicated it had absorbed water but it wasn’t in the critical range. Yet. Originally it came with DOT 3 fluid, replaced the entire fluid system with DOT 4.

[FIRE UP]

You state "I-8 east"? I thought you were heading TOWARDS SAN DIEGO, not away from it. Mountain Springs Grade, between San Diego and El Centro is a somewhat steep grade. But, there is at least ONE if not two, run-a-way truck ramps on that direction. I don't know if any of you have actually walked on a run-a-way truck ramp but, the design of them the type of gravel/stones they use, almost cause YOUR FEET to sink when you walk on them. They slow a big-A$$ truck down IN A HURRY!

As for the periodic brake fluid change, yes, that's been a given in just about all gas powered coaches for eons. And, it's not rocket science. Two people, who have even reasonable mechanical knowledge, can replace ALL the brake fluid in even the largest class A gas in less than an hour. Just because a system is working as it should, even after say 4-5 years without touching it, doesn't mean it should be left that way. The manufacturers do a pretty good job in the creation of the brake systems on all our vehicles. But, MAINTENANCE is still the name of the game here, for those systems to continue to work as designed.
Scott

[Ray,IN]

Ford recommends replacing brake fluid every 3 years, as does BMW and Mercedes. Look it up.

[NeilV]

Originally Posted by Ray,IN

Ford recommends replacing brake fluid every 3 years, as does BMW and Mercedes. Look it up.

On the F53 chassis service manual that came with mine it lists that in Motor Home use you have to follow the Severe Service Schedule where you need to drain, flush and refill the brake system every 2 years.

When you crest a hill in the mountains you need to already be out of overdrive before beginning the descent and should not be picking up any speed since motor home tires are only rated for 75 MPH MAX. The emergency brake thankfully on the F53 is separate from the service brake so even when you have a total service brake fail you can supplement with the emergence brake which is a drum brake on the tail piece extension of the transmission. Don't forget to pump the brake pedal too to try and re-establish some service brake performance.

Be careful about upping brake formulations especially on older vehicles as I have had some rubber parts in older brake systems not react well to the newer more synthetic brake fluids. Lost the rubber cups in the master cylinder and had a few brake hoses swell closed on one vehicle that was rated for DOT3 and it appeared that even though those components had recently been changed they were New Old Stock parts not formulated for use with the newer brake fluid formulations. The new parts that came in to replace those that failed were not all rated for the new formulas so we flushed the system out with DOT3 before installing the new parts and refilled it with DOT3 to prevent a recurrence and the brakes have been trouble free ever since then following the 2 year drain, flush and refill schedule.

Hydraulic Clutch Systems that use brake fluid also need to be drained, flushed and refilled every 1 to 2 years too since many of them do not have the diaphragm cap to prevent contamination with humidity like a brake master cylinder has.

[falconview]

https://www.cashcarsbuyer.com/dot-5-brake-fluid/

[frizfreleng]

Next you are going to tell me I should change the engine oil.

[AirBossdavid]

I was scared just reading that. Nice we still have you and your wife with us!

[astrnmrtom]

Great story. Wow!

For the average person driving a daily driver back and forth to the office and grocery store you can go the life of your ownership ignoring fluid changes except for engine oil, and I suspect most people do. That's why when I purchase a used vehicle unless it has records of it being done, I assume ALL fluids need to be changed. I see changing brake fluid to be about as important as changing motor oil. One is part of the system gets my RV going, and the other one, stopped.

My previous rig was on the P-chassis so was pretty heavy for the brake system, and I treated it as such. Only had one pucker moment with the brakes. We'd just come down a long grade that leveled out at the edge of a town. I was careful, and all seemed fine until the light at the first intersection turned red. I applied the brakes as normal and I didn't slow. It was like that feeling when you slide on ice. I pushed hard and finally rolled to a stop just past the limit line, short of entering the intersection. Thankfully I was going slow. I got out to do a quick visual, only noticed a slight smell of hot pads, and continued on slowly. The next stop the brakes worked fine. It never re-occurred. Ambient temps were around to 100.

Only thing I could figure was it was a perfect storm - high ambient temps and the grade ending in a low speed stop that didn't allow enough airflow to cool the brakes so despite the fact the grade had ended, and the brakes were no longer being stressed, the brake temps continued to climb as I slowly rolled into town. I don't think it was the fluid because my brake pedal feel was normal, it's just like the pads lost almost all their friction for a moment.

My current rig has a pack brake, which really helps, and I strictly stick to the don't do down any faster than you went up rule. Can't say there's been a grade yet where I felt I was stressing the service brakes, thank goodness. I'm glad it turned out ok for the OP. When things like that happen, it show just how quickly thing can go sideways. One minute all is fine with the world, the next, you find yourself just trying to survive.

[roadrunner 2]

Thank you for all of the comments.
The Fleetwood was the Chevy chassis. The e brake was a trans brake as it was explained to me at the time. 8 yrs ago.
When we hit the top of the grade the brake light came on, we were driving up and never used the brakes. The light just came on right at the top of the grade as we crested. The rotor was hanging up. I had never noticed it because we use it for short trips.
It must have dragged for some time. I never smelled any brakes on any drive. Both times it happened it was after driving 2 hrs or more. Slowly heated up over time.
We traded it in for a Tiffin 36la. Good times again.
Special thanks to those for explaining the difference in the Dots. hope it helps others.
Don't forget to change the brake fluid. We have a guy who comes to the house ever 3 yrs to change it.

[astrnmrtom]

One note for anyone with a similar dragging brake issue. One thing that could happen on older rigs was the brake hoses would swell inside and not allow the pressure to bleed off the calipers which caused the brakes to drag. It was just barely starting to happen on our '96 P chassis rig. I replaced all the rubber brake lines. Wasn't expensive or too difficult. Some of the fittings can be a bear to remove so make sure you use a brake fitting wrench. I pre-sprayed all mine several times with PB Blaster.

[bsinmich]

That was one of the problems with the big Workhorse problem on the W22 chassis. Thei brake cylinder pistons would absorb moisture. They replaced all calipers and it was cured.

[alton]

Had they address the problem when it occurred they maybe would still be in business united of watering 5 years. That brake problem cost me a bundle and when the recall finally happened it was a halfway job.

[mickeybitsko]

I'm sure you're an excellent driver, but, I suggest the op take a driving lesson.
One that teaches you how to go up a steep grade AND go down a steep grade.
There is a technique.
Good you didn't kill yourselves or someone else.