Thread: 53 Is back from the Body Shop

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There is a brake line valve called a hold off valve. It goes in the line to the front brakes and prevents them from operating until the line pressure reaches 100 psi or so. It is intended to allow rear drum brakes to catch up with front discs, since the drums have farther to move. Most distribution blocks for disc/drums have one built in.

I had an issue on my T bucket with the rear brakes not doing much, but they were drums front and rear. I installed stand alone hold off valve and it seemed to help. I know you have discs front and rear, but it sounds like you are having a similar problem. It may be worth a try if nothing else works.

It could also be a pad material issue. The brakes may actually be working as far as hydraulics, but the pads in the rear are harder and never getting up to operating temp.

I remember reading that on the S10 rears, GM was having an issue with rear brake lock up. This was in the days before anti-lock. Their solution was to use metallic shoes and very small wheel cylinders. This effectively prevented the rear brakes from doing much until the line pressure was very high and there was a lot of heat in them, like when hauling or towing heavy loads. This came from another forum, supposedly from a brake engineer familiar with the story. I do know that the S10 rear wheel cylinders were only 3/4" bore! Ford may have done a similar trick with the Explorer rear brakes. FWIW - I have Explorer rear brakes on my 46 and have never been completely satisfied with them either, but they worked well enough that I never got around to working out the reason why.

Going to a softer, higher friction pad material, may solve your problem. Seems like I remember that you are using an Explorer rear. I'm sure someone like EBC probably makes replacement pads in various known compounds. Going to something like EBC Yellow Stuff pads front and rear may make a difference. You could also look for full organic rear pads from the local parts store if they are available. Look at their cheapest line of parts. They should be softer and have a higher friction.

This is a typical hot rod issue. We take parts from different manufactures or different vehicles by the same manufacturer and hope that they will play nice together. Sometimes they don't. That's when you just have to give it some thought and start making changes.

Also, the Expedition calipers will fit on the Explorer brackets or at least they look like they should. They have a larger piston than the Explorer calipers. This would increase the clamping force a little. I have never made the swap, but plan to in the future on my 46 coupe. I suggested this to 40FordDeluxe and I think he either did it or at least tried it. He should have the details.