hydroboost issues

Kspen90

<<<got turbos?
Jul 14, 2011
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Burleson, Tx
So lately I've noticed decreased performance from my hydroboost pump, mostly in the brakes. It seems like I have to push the pedal harder to achieve the same braking power than i did 6 months ago. Also the past couple times I've done one of my high speed late night backroad runs after a series of hard cornering and braking the pump begins to whine as if it is out of fluid and I feel the vibration in the brake pedal. I've done some research and it seems that flushing the system and replacing the fluid with synthetic helps some but I am also curious are there any pump upgrades such as putting a smaller pulley on the pump or a whole new performance pump of some sort? Also does anyone know what actually causes the whining condition of the pump? Is it overheating of the fluid? If so I was thinking of installing a trans cooler in the hydroboost system? Any input is appreciated.
 

messejme

Jazzy, Me and Max
Mar 7, 2008
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Branchburg NJ
Hydraulic pumps wear out eventually. Even the fluid movement will erode the metal given enough time but contaminants in suspension will speed up the process.
 

mb1

Member
Nov 15, 2009
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Edmonton, Alberta
IMO start with changing out the fluid and then see if you want / need to do more. Fluid flush did make a big difference on my '07, I would think your '02 would have at least as much to gain.
 

Kspen90

<<<got turbos?
Jul 14, 2011
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Burleson, Tx
IMO start with changing out the fluid and then see if you want / need to do more. Fluid flush did make a big difference on my '07, I would think your '02 would have at least as much to gain.

That's definitely coming this next weekend. It especially needs it now since the other night, while drunk, I was doing a bit of "problem solving" and at the time was only thinking of the problem from a braking issue standpoint and associating brakes with brake fluid and for some reason was thinking it took DOT3 and poured higher temp DOT4 in it in an effort to "fix" the issue :eek:
 

mb1

Member
Nov 15, 2009
149
0
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Edmonton, Alberta
Replacing the brake fluid wouldn't be a bad idea either.

Sorry I'm not 100% clear on what you did there.... you put DOT4 brake fluid in the PS/ Hydroboost system?
 

BlkMax

Member
Sep 1, 2008
743
4
18
Wasilla, AK
You might have an issue with the accumulator in the hydraulic side of the system. If you want better braking, replace the hoses at the same time as the flush. I put braided steel lines on and there is a NOTICEABLE difference in the feel of the pedal: http://allseasondieselperformance.com/index.php?main_page=product_info&cPath=99&products_id=258 On edit: There are also other places to get those lines, I just remembered that link.

No more expanding hoses...I learned that trick on my motorcycles, much better brake feel with the braided hoses.
 
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Kspen90

<<<got turbos?
Jul 14, 2011
1,433
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Burleson, Tx
that can"t be good

2 things:

dont drive it till you pour that brake fluid out and flush the system

Quit drinking, thinking, and working on your truck at the same time. :D :hug:
Yeah, that occured to me when i woke up the next morning but after a few drinks and a 12 pack it seemed like a great idea :rofl: But its sitting at home right now, Ive ordered an aftermarket cooler from autozone and im going to flush it and replace it with synthetic.
 

Kspen90

<<<got turbos?
Jul 14, 2011
1,433
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36
Burleson, Tx
You might have an issue with the accumulator in the hydraulic side of the system. If you want better braking, replace the hoses at the same time as the flush. I put braided steel lines on and there is a NOTICEABLE difference in the feel of the pedal: http://allseasondieselperformance.com/index.php?main_page=product_info&cPath=99&products_id=258 On edit: There are also other places to get those lines, I just remembered that link.

No more expanding hoses...I learned that trick on my motorcycles, much better brake feel with the braided hoses.
Ive considered this already after looking at the trans line kit but i didnt know they made a prefab one for the ps unit. Thanks for the link
 

Darius6t9

I'm the Floater. Lurking.
Aug 23, 2008
574
0
0
Rusk, Tx. Again
Take this for what you want. But I had an ex-girlfriend that put powersteering fluid into the brake res. She cycled the brakes a couple of times while driving. She told me about it cause her brakes started to not work. I opened the cap and the rubber there was swelled so much the cap wouldn't go back on. I pulled the front calipers and the rubber seals were somewhat swelled as well. I ended up replacing ALL of the rubber in the brake system. Along with a new master cylinder. And yes, the seals in the master cylinder were swelled as well. I don't know if the same thing would happen with the powersteering system or not. But it is something to keep in mind if you start having issues with your brakes and/or your powersteering.
 

Chevy1925

don't know sh!t about IFS
Staff member
Oct 21, 2009
21,690
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Phoenix Az
Yeah, that occured to me when i woke up the next morning but after a few drinks and a 12 pack it seemed like a great idea :rofl: But its sitting at home right now, Ive ordered an aftermarket cooler from autozone and im going to flush it and replace it with synthetic.

bit off topic BUT ill give you this, ATF does well in a tight pinch if you lost most of your brake fluid. We had a buddy loose a brake line out on the trail one night in his bronco II. we crimped off the back rubber hose and bled the other three brakes with ATF fluid as it was all we had. Worked well, flushed the system back out once he got home and no adverse affects since (this was 5 or so years ago). i wouldnt leave it in for a long period though
 

Kspen90

<<<got turbos?
Jul 14, 2011
1,433
0
36
Burleson, Tx
Well I've ordered in a ps fluid cooler and royal purple syn. ps fluid and will do the flush tomorrow night and let everyone know the results. By adding the cooler to the return line I'm hoping the increased capacity and cooler will fix the problem. If I keep solving problems at this rate ill be ready to dust my buddy's miata by the end of the summer! :rofl:
 

Darius6t9

I'm the Floater. Lurking.
Aug 23, 2008
574
0
0
Rusk, Tx. Again
bit off topic BUT ill give you this, ATF does well in a tight pinch if you lost most of your brake fluid. We had a buddy loose a brake line out on the trail one night in his bronco II. we crimped off the back rubber hose and bled the other three brakes with ATF fluid as it was all we had. Worked well, flushed the system back out once he got home and no adverse affects since (this was 5 or so years ago). i wouldnt leave it in for a long period though

A guy I work with, his dad runs atf in his ford ranger brake system. Don't think he has had any issues with it yet.
 

Kspen90

<<<got turbos?
Jul 14, 2011
1,433
0
36
Burleson, Tx
Just finished up the cooler install and flush and refilled with royal purple synthetic fluid, and wow! What a difference it made! I can sit dead stopped on pavement with my 305's and push the brake all the way to the floor and turn the steering wheel from lock to lock with two fingers easily! The difference in the braking response is night and day too! I've got pics if anyone is interested in seeing them.
 

06_6.6

Haulin Assphalt
Sep 3, 2012
159
0
0
Indian Territory
Just finished up the cooler install and flush and refilled with royal purple synthetic fluid, and wow! What a difference it made! I can sit dead stopped on pavement with my 305's and push the brake all the way to the floor and turn the steering wheel from lock to lock with two fingers easily! The difference in the braking response is night and day too! I've got pics if anyone is interested in seeing them.

Im in if you still have them. That sounds like a mod well worth it.

Sent from the drivers seat of an 06 dmax
 

Kspen90

<<<got turbos?
Jul 14, 2011
1,433
0
36
Burleson, Tx
Ill post them when i can figure out how to do it from my phone. I was extremely simple though, i just bought the cheap $20 2 pass cooler from autozone and mounted it to the condenser and plumbed it into the return line that comes from the top of the master cylinder and goes to the back of the PS resevoir. Between the cooler, the added capacity from the extended amount of lines, and the Royal Purple synthetic it made a huge difference.