I recently put a new rear differential in my truck. When I was done I bled the rear brakes and everything worked fine. But now my front brakes do not work. It was snowing yest and I would slam on the brakes and my back tires would lock up and that's it. Fluid level is full and I tried bleeding the front brakes and no fluid comes out at all. I put new pads on about a month ago and had no probs.


Suggestions.....?

 

Yeast? Yesterday?

With nothing in the bed the rear end is relatively lightly loaded; you'll be able to make the rear slip long before the front will (as the weight is transferring to the front when you brake as well). Were you able to stop? Or when the rears locked up did you just roll right off the road? I can't say that your fronts ARE working, but if that is the only test you did I don't think you know either.

 

there is a valve that has a rod that connects to that rear diff that may be adjusted wrong. i'll see if i can pull the thread. easy fix.

here it is. https://www.yotatech.com/forums/f116...highlight=LSPV

good info in that thread. read up mang.

 

Could be that the master cylinder has gone out. My 82 did the same thing some years back. Replaced the master clinder and fixed the problem!

 

It could be a number of different things....since yours rear brakes are locking up the tires, that would kinda rule out master cylinder for me...The master cylinder went out on my 87 and the only possible way I could slow down was downshift like hell...
My guess is your callipers might be locked up...
I'm on my cell phone right now, so I can't find the thread.
But there was a guy on here not to long ago that was having similar problems, I told him to replace the front brake callipers because my girlfriends Z71 did the same thing the other night...those pistons are probably froze up...therefore when you try to bleed the front brakes, you're not getting any fluid to the bleeder valve...
You might try replacing those callipers (not rebuilding, replacing) most of the time when people rebuild the callipers, they have a tendency to go out a lot sooner than they should...I wouldn't risk it to save a couple bucks.

 

I still would not rule out your master cylinder. Being that you were in the snow and locking up the rear tires is not uncommen and the chanses that BOTH calipers siezing up at the same time are pretty slim.

 

This is also true, but if he bleeds the rear brakes but can't bleed the front, wouldn't that mean that the master cylinder is indeed working?
Go to a gravel or dirt road without snow and try again to see what happens...

 

Not necessarly. Toyotas master cylinders are on two different systems (Front and rear) in side the master cylinder so you can loose you front brakes but still have rear brakes and vise versa kind of a safety system.

 

Well I learned something today haha.
Alright, let's go ahead and say...the master cylinder is a good possibility.
Take a look at your brake callipers and if the pistons are rusted, or seem seized...

 

I'm glad I could be of some learning assistance. You can never know to much about these addictions.........I mean vehicles! LOL!

 

or remove and compress the caliper and see if she sinks in nice and easy. that'll tell you if its seized or not.

 

I agree that it is very unlikely that both front calipers would seize at the same time, even if they are seized you would still be able to gravity bleed them. I would also think that it is the master cylinder that has gone bad.

 

havin same problem b4 today all i had was front brakes,found a day off today and bled the rear brakes adjusted eberything now i dont have front brakes no fluid when bled nothing!!! I was thinking mc THANKS GUYS!!!!

 

bleed left rear, right rear, left front, right front... then the proportioning valve (LSP-BV) in the rear.

Should take you about 1 pint of fluid to flush / bleed them all.

 

ok will do first thing morning dont havebe work till after noon tomorrow so do that first thanks

 

If theres no fluid coming out of the lines, try and unscrewing the flare nuts at each line junction and bleeding the lines, then the calipers.
if theres still no fluid, you could possibly have pinched lines, or bad calipers.

 

well theres no fluid coming out of mc to the front lines just bled and still nothing so figured id try the mc and nothing for the front really blows out the back though!!!

 

Time for a new master then.

 

yup put on this morning and BAM!!!! GOT BRAKES!!!!

 

I have a 91 Toyota pickup I had to replace a wheel cylinder on driver side. I've bled the brakes atleast 10 times and still have no front brakes. I was wondering cousin it be my master cylinder. Please reply ASAP