Must be time to find a older truck.

The brakes on my F350 have been a little screwy for the last couple of months. I figured master cylinder. Soft pedal, creeps to the floor under pressure, the usual. So I did that today. Should have been a easy swap, right? Wrong.

Get it all back together, bleed the system, jump in the truck for a test drive and with the engine running, the pedal goes straight to the floor. WTF? Re-bleed the system, this time the old fashion way. Fire it back up and the pedal goes straight to the floor. berkeley!

Time to hit the internet and see what the berkeley is going on. My guess is bad master again, but with the engine off, it has a hard pedal. Something funky is going on.

Turns out, this piece of E36 M3 has rear ABS. I bought a old truck so I wouldn't have to screw with this kind of crap. Apparently it hasn't worked since I bought it because I've locked the rears a couple of times.

Buried under the truck is a crappy module to dump pressure off the rear circuit if the rears lock up. Apparently they fail often.

Might be time to pitch that crap for a good old fashion proportioning valve. I've got some more research to do.

I had a truck that someone had put a nail in the rear circuit of the master cylinder because they were too cheap to replace the rusted through rear line. Took me forever to figure out why I couldn't get the rear to bleed.

my girlfriend's 64 Chevy doesn't have anything resembling ABS.. it also has drum brakes all around, which should be fun for her once we get it on the road since everything she's ever driven has had ABS..

Not wanting to replace one part justifies ditching an entire truck and looking for something from the neanderthal era?

The brakes on old trucks suck. Going from all-manual to power brakes, ABS and power steering on my '93 was like going from a horse carriage to a King Ranch edition. I have no desire to ever go back unless its for a restored antique that just cruises to car shows.

Have you seen my truck? I think the electrical system might have fuses.

Well it is a Ford so I wouldn't be surprised that something stupid like this happened. I would also expect it to cost a small fortune to fix

i ditch the rear abs pump every time i need to switch a rear line on an 88-94 chevy.

patgizz wrote: i ditch the rear abs pump every time i need to switch a rear line on an 88-94 chevy.

Might as well. I don't think I've ever seen one of those with a module that works, anyway.

i pulled the ABS fuse on my 97 Chevy because it has a bad wheel sensor somewhere and put the pedal on lockdown while the solenoids in the abs module went crazy every time i tried to stop the truck. i got the truck from my brother, who said it did that for the whole 2 years he had it... pulling the fuse has had no negative impact on the way the truck drives or stops other than setting the ABS light in the cluster, which i've learned to ignore. drove it on glare ice this winter and never felt like it was necessary to have it..

Rear abs on my 89 chevy went bad. After no less than six junkyard trips to attempt a repair, I bypassed that E36 M3. Stopped better than ever.

My current truck doesn't have abs.Stopps wwonderful. Except in the rain. Wilwood h pads don't like rain.

I'm leaning toward scrapping the ABS. The RABS valve is $$$ and apparently getting two years out of one is considered good. For now I've pulled the spring out of the accumulator and it's stopping better than ever. A little plumbing and a adjustable proportioning valve might be in order.

patgizz wrote: i ditch the rear abs pump every time i need to switch a rear line on an 88-94 chevy.

Sound preventative repair. RWAL systems almost universally sucked as far as this failure mode is concerned.

To the OP: You shouldn't need to worry about a proportioning valve. The ABS doesn't do brake proportioning until you get into the much more modern active-proportioning systems. ABS that old is purely a reactive device, not proactive.

Well, I suppose it is possible that Ford might have stuck the prop valve on the ABS unit's inlet. But as a rule, any proportioning valves are upstream of ABS.

Knurled wrote: Well, I suppose it is possible that Ford might have stuck the prop valve on the ABS unit's inlet.

From what I've been reading, that's exactly what they did.

Toyman01 wrote: The RABS valve is $$$ and apparently getting two years out of one is considered good.

Called it.

ddavidv wrote: Not wanting to replace one part justifies ditching an entire truck and looking for something from the neanderthal era? The brakes on old trucks suck. Going from all-manual to power brakes, ABS and power steering on my '93 was like going from a horse carriage to a King Ranch edition. I have no desire to ever go back unless its for a restored antique that just cruises to car shows.

I dunno, the manual all drum brakes on my 66 F250 kick ass. I was actually pleasantly suprised at how well they work.