Hooray - first post!

Talking 1991 F250 5.8L 4X2.. trying to fix basic sinking pedal issue.

Questions about RABS....2B373 is the Ford part # in the manual, but I'm seeing a lot of OEM valves that have 2B373-x something on the end. for Example 2B373-HRM or 2B373-A. I cannot find a reference to the trailing information. Are these manufacture updates or do I need more specific information before purchasing?

Trying to decide re-man valve or OEM.
Does the forum gods recommend a re-man or do you recommend going with one of the updated OEM valves? On eBay the price is around $200/$250 depending.

Thanks for your time.
P.S. "Checking OBDI codes (EEC-IV) " link is broken in the technical sticky post.

 

What makes you think it's the RABS valve causing your sinking pedal?

 

the extra letter is nothing more than the number of the update to the part number.
before wasting money on an ABS valve, try bypassing it to see if it is in fact the problem.

 

Thanks for answering my question about the part #.

I guess I should say low pedal not sinking pedal.

I've replaced the pads, rotors, master, drums and shoes so far. I've followed the bleed procedure as recommended on this forum RR, LR, RABS, FR, FL.
I've also adjust the boost rod into the master cylinder.

Given that not sure what else it could be?

 

I will re-bleed the entire system again and make sure the rear are adjusted until just a slight drag is notice. FYI: My E-brake is excellent and under hard braking I get rear wheel lock. IDK; feel like this low spongy pedal thing isn't really answered directly on the forum

I tend to throw money at the problem.

 

the master cylinder on the 250 is too small and usually gives "that sinking feeling"
BUT bypassing the RABS valve most of the time eliminates the sinking pedal.
i guess as they get old they fail internally and bleed off pressure.
the abs on my 88 has been bypassed since the truck had 400 miles or so on it. the dealer could not figure out why i would just loose brakes and run red lights, and then ten seconds later hit the brakes and kiss the windshield. so they tried bypassing the abs and the brakes were perfect. and have stayed that way ever since.
the only vehicle i own that has ABS is the 2014 superduty. all 9 of the others either never had ABS, or it was been disabled as soon as i got it

 

The dealer by-passed or disabled the ABS on a new veicle with 400 miles and you accepted it...

 

1997 F350 master cylinders have larger bores and provide better performance. May want to swap it while you are at it.

 

they wanted to order a new RABS valve, but since everything i have ever driven before that and since until i got the 2014 in january has never had abs anyway, so it was not a big deal to have a new vehicle with working brakes.

 

Kinda confirms my thoughts on the RABS. I guess it begs the question are the updated valves any better?

 

probably not.

 

There's a lot of bad information out there about these trucks but this is about the goofiest bunch of BS I've ever heard.

 

I'm glad you took the time to provide some actual useful info as well!

 

True; Kinda off topic but the valve update was the question and reman or OEM

 

https://www.ford-trucks.com/forums/3...ellow-red.html

This links to the best information that was out there twelve years ago. It's mostly all gone now. I posted to to a thread recently that was as good as it gets now. Even idiots need good brakes.