Hey guys, I'm looking for a little advice here, totally new to the forum.....I have a 95 2WD PSD with a 5 speed manual, truck is totally stock except for an engine brake and an auxiliary fuel tank...I'm using it to tow an 8500 pound trailer and am currently 500 miles from home and having lots of problems..

Yesterday I got the truck back from the Ford dealer who put on a new slave cylinder and master cylinder on the clutch....Was test driving it today before hooking up the trailer and the cruise control wouldn't work, then I get a red light on the dash... Brake....Stepped on the brake pedal, felt like a rock, no power.....light went off for a few seconds and the brakes were back and then went out again.....Checked the brake fluid when I got it stopped, it's right up where it should be....Any ideas as to what could be the problem??

 

For the Cruise control check the electrical connector on the very front of the brake master cylinder. They might have accidently unplugged it while doing the other repairs. Also check to make sure there is not any brake lights out include the third brake light on the cab.

The hard brake pedal was from a lack of Vacuum for the power brakes. Its possible you have an issue or its possible you just stepped on the brake a lot and depleted the reservoir though if the truck was running that should be very hard to do. Check the Vacuum pump (small pulley between the A/c and Power steering pumps. make sure there is not oil coming from the front of the vacuum pump and that pulley looks straight. Its very common for the bearings to go out of the vacuum pump which causes the failure.

Oh yeah Welcome to FTE!

 

a blown brake light fuse will make the cruise control not work, the dealer cutting the wire for the recall will make the cruise control not work, a clumsy mechanic can knock off a vacuum line causing not enough vacuum for the brakes. if it is a vacuum problem your air conditioner will stay on defrost.

 

Thanks for the replies guys... The brake lights are working, all 3 of them... I checked the connector for the cruise and it is connected, the cruise was working earlier this morning but the light for the cruise on the dash was not...Then the cruise stopped working just as the brake light came on...I checked that vacuum pump and can 't see any oil around it, the pully looks straight to me.

 

Sounds vacuum related, check the exhaust brake as well as any other areas that use vacuum, heater vents front axle etc.. if it is a vacuum brake it may be leaking.

 

Don't diesels have a hydro-boost system? Both of mine do.

 

Your OBS is the exception. The OBS F-superduty (f-450) has hydroboost and the newer F-250/350's do but not the OBS 250/350.

 

Didn't know that, thanks for the info.

 

OBS don't have vacuum brakes. The EBPV is not vacuum either. The 4X4 is not vacuum as well. The only thing that is vacuum is the brake booster and the heater vent controls. Look there.

 

Thanks for all the replies.. Had the truck towed into a Ford dealer today, it was the vacuum pump, they put a new one on and it runs like a champ now...