****** http-equiv="Content-Type" content="text/html; charset=utf-8">****** name="ProgId" content="Word.Document">****** name="Generator" content="Microsoft Word 10">****** name="Originator" content="Microsoft Word 10"><link rel="File-List" href="file:///C:%5CUsers%5CJSA-5%5CAppData%5CLocal%5CTemp%5Cmsohtml1%5C02%5Cclip_ filelist.xml"><!--[if gte mso 9]><xml> <w:WordDocument> <w:View>Normal</w:View> <w:Zoom>0</w:Zoom> <w:Compatibility> <w:BreakWrappedTables/> <w:SnapToGridInCell/> <w:WrapTextWithPunct/> <w:UseAsianBreakRules/> </w:Compatibility> <w:BrowserLevel>MicrosoftInternetExplorer4</w:BrowserLevel> </w:WordDocument> </xml><![endif]--><style> <!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0in; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman";} @page Section1 {size:8.5in 11.0in; margin:1.0in 1.25in 1.0in 1.25in; mso-header-margin:.5in; mso-footer-margin:.5in; mso-paper-source:0;} div.Section1 {page:Section1;} --> </style><!--[if gte mso 10]> <style> /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman";} </style> <![endif]--> I have a 1999 ford super duty pickup the truck has a hydroboost power brake system and when I step on the brake pedal when the truck is stopped. The power steering is very hard I release the pedal the steering is fine.


****** http-equiv="Content-Type" content="text/html; charset=utf-8">****** name="ProgId" content="Word.Document">****** name="Generator" content="Microsoft Word 10">****** name="Originator" content="Microsoft Word 10"><link rel="File-List" href="file:///C:%5CUsers%5CJSA-5%5CAppData%5CLocal%5CTemp%5Cmsohtml1%5C03%5Cclip_ filelist.xml"><!--[if gte mso 9]><xml> <w:WordDocument> <w:View>Normal</w:View> <w:Zoom>0</w:Zoom> <w:Compatibility> <w:BreakWrappedTables/> <w:SnapToGridInCell/> <w:WrapTextWithPunct/> <w:UseAsianBreakRules/> </w:Compatibility> <w:BrowserLevel>MicrosoftInternetExplorer4</w:BrowserLevel> </w:WordDocument> </xml><![endif]--><style> <!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0in; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman";} @page Section1 {size:8.5in 11.0in; margin:1.0in 1.25in 1.0in 1.25in; mso-header-margin:.5in; mso-footer-margin:.5in; mso-paper-source:0;} div.Section1 {page:Section1;} --> </style><!--[if gte mso 10]> <style> /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman";} </style> <![endif]-->I just replaced the power steering pump, it didn't fix the problem.
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Hi kc0ti1002 and welcome to FTE.

OK, as you probably already know, hydroboost brakes are powered by the power steering pump. You have replaced power steering pump but still have the problem of hard steering during braking.

Aside from the new pump also being bad, you also need to check the power steering fluid level and the serpentine belt. You could also have a problem with the hydroboost unit and possibly the master cylinder.

 

Thank you, I replaced the fluid and the belt is new. I also noticed the old fluid is red? any way thank you for the info I will look in to the booster assembly next.

 

The old fluid is red because its transmission fluid. Our trucks use transmission fluid in the power steering system and NOT power steering fluid.

 

Some superduties just do this. My steering binds when i try to turn the wheel with the brakes on when stopped. Makes parallel parking a PITA.

 

Time to flush your P/S system

 

Your truck should not do that. You don't have a hydroboost system, so braking and steering are not on the same system. Brakes on gas engines run on vacuum.

 

Indeed, however I was told that it was because the front wheels rotate a little when you turn the wheel. When you apply the brakes it doesn't let the wheels rotate. I wanted to test this by putting the front of the truck in the air and trying it, but i never found the time.

 

Thanks for all the help

 

Hey redford, if the truck is a dciesel it has a hydroboost system

 

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Yes. Gas engines use vacuum for power brakes and the diesels have hydroboost.

 

i think they all gotta have hydrabooste after 10.000 gvw gas,deisel or nucaler

 

I thought it was just because diesel's don't create vacuum like the gassers do...

 

you are wright stinkers blow gassers suck

 

X2 To test, just put in park and rotate the steering wheel.