Nissan XTerra Forum banner

Still having soft brake pedal....

21K views 13 replies 4 participants last post by  Jbat 
#1 ·
Replaced the rotors, pads, drums, shoes, wheel cylinders, master cylinder, and rear brake lines. Literally the only thing that I didn't change were the calipers and front brake lines, although I don't think these would cause a soft brake pedal... or would they? Lines were bled several times. The soft brake pedal problem continues.

I've read that I may need a bigger master cylinder from a 1/2 ton truck, but I don't know which ones to look for or how to install them. I've had other people say that the stock master cylinder should be fine and that my problem lies somewhere else. I'm really not sure what to do at this point, but it's annoying. I shouldn't have so much play in the brake pedal.

Any suggestions?
 
#2 ·
Turn ignition switch OFF and disconnect ABS actuator
connectors or battery ground cable.
I Bleed air in the following order.
1. Left rear brake
2. Right rear brake
3. Left front brake
4. Right front brake
SBR419C
1. Connect a transparent vinyl tube to air bleeder valve.
2. Fully depress brake pedal several times.
3. With brake pedal depressed, open air bleeder valve to release
air.
4. Close air bleeder valve.
5. Release brake pedal slowly.
6. Repeat steps 1. through 4. until clear brake fluid comes out of
air bleeder valve.
7. Tighten air bleeder valve to specified torque.
: 7 - 9 N·m (0.7 - 0.9 kg-m, 61 - 78 in-lb)
DID YOU DO ALL OF THIS?
 
#4 ·
Thank you for the suggestions.

Master cylinder was bench bled. Everything bled in order. The only thing that was not done was to disconnect the ABS. Will try that next.

I spoke to my mechanic and a new ABS pump is a $1249 dollar part brand new. He doesn't want to try a used one because if that one is faulty too, we'd be chasing our tail on the problem and never find a solution.

Can I just keep the ABS disabled? If not, since used ones are only about $100 bucks, can I just buy a couple of them and try them out to see if it works? They can't all be defective, can they?

Are they hard to install?
 
#6 ·
Mine failed at 61,000 miles. The genuine Nissan replacement failed instantly upon installation. Six days to get one from Japan and it failed. Two days later another one comes in from Japan and it was fine, Your mileage may vary.
Good to know. How do you know they failed? Does it throw the ABS light? Some other code? I've had no lights coming on, but the mechanic still thinks it may be defective and that's what is causing the squishy brake pedal and intermittent "vibration" when braking.

Could I just bypass the ABS?
 
#7 ·
Good to know. How do you know they failed? Does it throw the ABS light?
Dealer diagnosed and replaced all three. Two failed in the service bay before the truck came off the lift. No issue with the truck and I was told the modules were known for this type of failure right out of the box.

On mine it was a series of come and go ABS lights followed by failure of the ABS system. Firm pedal and it stopped fine but it would lock all four wheels.

Some other code? I've had no lights coming on, but the mechanic still thinks it may be defective and that's what is causing the squishy brake pedal and intermittent "vibration" when braking.
It could I'm not that familiar with ABS type systems but brake systems I am very familiar with and soft pedal to me indicates air in the system.

Another thing to look at are the rear shoes adjusted correctly? Since they replaced the wheel cylinders I wonder if the rear shoes are adjusted correctly.

Could I just bypass the ABS?
You could, I wouldn't, but why not just find the issue and fix it?
 
#8 ·
Dealer diagnosed and replaced all three. Two failed in the service bay before the truck came off the lift. No issue with the truck and I was told the modules were known for this type of failure right out of the box.

On mine it was a series of come and go ABS lights followed by failure of the ABS system. Firm pedal and it stopped fine but it would lock all four wheels.



It could I'm not that familiar with ABS type systems but brake systems I am very familiar with and soft pedal to me indicates air in the system.

Another thing to look at are the rear shoes adjusted correctly? Since they replaced the wheel cylinders I wonder if the rear shoes are adjusted correctly.



You could, I wouldn't, but why not just find the issue and fix it?
I've tried to fix the issue. Replaced almost every single brake component on the truck, bled the lines several times, consulted with a Nissan technician who couldn't figure it out.... the pedal is never firm, and based on what I've read, it's supposed to be. I'd really like it to be. I don't know what else to do at this point.
 
#9 ·
You can bypass the ABS with a little time and a few fittings, you can also replace the master cyl with a dodge 1500 from around a '98 but you shouldn't need to with stock brakes. Either you still have a faulty component or there is air in your lines. Has the brake booster been replaced?

BTW I have a ABS block I just pulled off that had no issues id sell. I removed because I no longer have ABS sensors so it was useless


Sent from AutoGuide.com Free App
 
#10 ·
You can bypass the ABS with a little time and a few fittings, you can also replace the master cyl with a dodge 1500 from around a '98 but you shouldn't need to with stock brakes.
That's what I keep hearing. Some people have SAS and 35's and are still able to use the stock master, so I don't know why I would be having such a soft brake pedal.

Either you still have a faulty component or there is air in your lines. Has the brake booster been replaced?
It has not. I didn't even think about that.

BTW I have a ABS block I just pulled off that had no issues id sell. I removed because I no longer have ABS sensors so it was useless
Definitely interested. Send me a PM with your price.
 
#11 ·
Actually never mind, the brake booster was changed recently
 
#12 ·
Yeah I know a lot of people haven't had issues even with swapping to solid axle, my brake system was already apart and my front calipers are HUGE so I didn't want to chance it and went ahead and swapped it out for the dodge unit


Sent from AutoGuide.com Free App
 
#13 ·
Yeah I know a lot of people haven't had issues even with swapping to solid axle, my brake system was already apart and my front calipers are HUGE so I didn't want to chance it and went ahead and swapped it out for the dodge unit


Sent from AutoGuide.com Free App
What did you have to do in order to install it? Any modifications? Did you have to add a proportioning valve?
 
#14 ·
What did you have to do in order to install it? Any modifications? Did you have to add a proportioning valve?

It was pretty straight forward and easy actually. I wrote about it in my build thread with pics but essentially it bolts right to the stock brake booster and then you need a 10mm bubble flare to 10mm inverted flare adapter for the front brake line to master connection and a 12mm bubble flare to 10mm inverted flare for the rear brake line to master connection. Then just bleed it good. I haven't driven mine yet so not sure just how good it is but its much larger than the stock one and will push much more fluid


Sent from AutoGuide.com Free App
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top