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Wayne, Journeyman
Category: Medium and Heavy Trucks
Satisfied Customers: 9449
Experience:  worked on, Gmc, Macks, Freight liner,Mercedes Benz,,Ford, sterling
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Replaced all vacum pumps but in gear light sounds an is

Customer Question

replaced all vacum pumps but in gear light sounds an is constantlt on
JA: What's the make/model/year of your truck? Engine type?
Customer: 99 iszu npr hd
JA: Are you fixing your truck yourself? What have you tried so far?
Customer: yes
JA: Anything else you want the truck mechanic to know before I connect you?
Customer: blead all brakes an smoked tested for leaks found nothing
Submitted: 9 months ago.
Category: Medium and Heavy Trucks
Expert:  Wayne replied 9 months ago.

Hi I'm Wayne

I will try to help you with this

do you have good brake pedal and Brakes ??

Customer: replied 9 months ago.
Brakes are ok but pedals firm until u drive then at a stop an go its firm
Customer: replied 9 months ago.
An hard to stop
Expert:  Wayne replied 9 months ago.

Thank you for that

above your rear end is a valve with a rod that goes the the rear

end housing this is a weight differential switch, that is a proportion

switch, Replace that

I hope this helped you

Hi. If this helped you,

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Expert:  Wayne replied 9 months ago.


Just following up wit you

did my answer help you ??

Let me know,Please


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