Good morning/afternoon Yotatechers!

So heres my issue. Brakes, I have changed soft lines booster and master cylinder. new calipers on the front. Rear wheel cylinders and everything look fine. Before the change, no brakes they went to the floor. now all the new parts the truck stops BUT... haha always a but. The pedal is stiff the rears will lock up fronts wont and its slow to stop. I have an 88 IFS T4R and the braking is different. the pedal is not as stiff as the 84. I did notice there is no LSPV in the rear which struck me as odd, I thought they had them. Lastly I noticed when you hit the brakes the emergency brake light comes on then will eventually go off again. Any input would be great!

Other than the brakes the truck runs like a top, little bit of play in the steering but that will get looked at once the brakes are fixed up.

 

I would venture to say that you need a proportioning valve to limit the fluid to the rear brakes. The front should do most of the work. The brake light coming on could be a result of fluid level drop in the fluid reservoir when you step on the pedal and send a lot of fluid down the lines. Top off the fluid and try it again.

In regards to a stiff pedal, booster would be my first guess. And vacuum source for the booster, or hydro assist source being you have a diesel. I don't know how Toyota does the brake assist on diesels. Sorry bro.....

 

Wilwood Manual Prop valve ordered. and the adapters to make it plumb in properly. hope this works.