new drums new spring kits new wheel Cylinder new Master Cylinder . still wheels lock up. could it be a ABS Hydraulic Unit ? done change the ABS Speed Sensor wheels lock up when I hit brakes done been bleeded front ok. just rear

 

for got to add. its on a 94 f150 4x4 5.0 auto trans tow package no 5 feet wheel ball tow only

 

1 more thing its a xl

 

friend put in spring kit not sure if its right or not when I wake up I will do a video I pull drums off on both wheels so you can see it. my truck been sitting for month need it fix ty for any advice

 

replaced Hydraulic Unit abs. if i start truck hit brakes rear wheels still lock up. new drums new spring kit new shoes i have crack open bleeder for wheels be unlock . any help please ty

 

Are you saying the rear wheels lock and don't let go when the brake is released? If so start by replacing the rubber flex line from the chassis to the axle and if that doesn't fix it replace the ABS module.

 

yes rear brake lock up after i let off pedal . so if i bleed lines wheel they turn when i start truck touch brakes they are lock up

 

I agree with Conaski on the rubber flex line. It is just under the bed, near the rear axle. When this line swells inside, it doesn't allow the fluid to release causing problems you have mentioned.

 

If the line didn't internally collapse try loosening the rear line on the master and see if it releases then, sometimes on after market masters they use bigger seals and it doesn't past the opening keeping pressure in the system, I have seen it on the front brakes as well as the rear, but it does sound like a hose, I have seen people vice grip the rear hose while replacing wheel cylinders so fluid doesn't make a mess that is the death rattle of the hose. they make a tool to clamp off the line without damaging it. Start there than work your way forward till you find the blockage.

 

its 10 am will have wait get the part later today. flex hose. when get new one in will update . been sitting past month cause we keep buying this and that for truck. i did see that abs relay has been taken out and 30 amp fuse out to. i just put new ABS Hydraulic Unit in. the abs light never been on. only when starting truck went out. i like to thank you all for advice.

 

update. put in a new rear flex hose still rear brakes are lock up . undid all abs still lock up . open bleeder they turn. when you start it touch brakes . they lock up again. now thinking run a straig line from Master Cylinder to rear or tie in from Master Cylinder do away with the abs unit. any help ty.

 

also where is ABS module on 94 f150 4x4 5.0 auto trans xl cruise controll ,? ty we did bleed the system

 

turn out was bad Master Cylinder. ty

 

Thanks for the feedback!