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Related Medium and Heavy Trucks Questions
Air in secondary tank will not build air over 50psi at idle.
Air in secondary tank will not build air over 50psi at idle … read more
Expert
Expert
10,503 satisfied customers
I have a 2014 CXU613 that builds air pressure and looses it
Mike I have a 2014 CXU613 that builds air pressure and looses it for no apparent reason. Changed filter and Purge Valve. No leaks anywhere from lines. It looses air while just idling with no one in th… read more
Joe Green
Joe Green
65 satisfied customers
2018 Mack mru613 with mo7 engine. Turbo cut off valve on air
2018 Mack mru613 with mo7 engine. Turbo cut off valve on air dryer has failed twice in the last week. What is causing this? What is fix?I confirmed that Governor is working as it should and Replaced t… read more
Mike Mcmillan
Mike Mcmillan
Triage Tech/Shop Foreman
Associates
561 satisfied customers
Having an issue with a 2018 international Prostar. The
Having an issue with a 2018 international Prostar. The primary and secondary brake pressure is constantly building from 120 to about 135 and the blows off back to under 120. It keeps repeating this is… read more
Mike Mcmillan
Mike Mcmillan
Triage Tech/Shop Foreman
Associates
561 satisfied customers
I have an 04 Mack cv713 the primary air system keeps
I have an 04 Mack cv713 the primary air system keeps building air well past 140 but the secondary only builds up to 130 and takes about 20 minutes to build that much I've replaced the governor and the… read more
Mike Mcmillan
Mike Mcmillan
Triage Tech/Shop Foreman
Associates
561 satisfied customers
1998 Freightliner FL80 Cummins 8.3 will not build pressure
1998 Freightliner FL80 Cummins 8.3 will not build pressure past 60 PSI on the service side … read more
Joel Bos
Joel Bos
909 satisfied customers
2005 mack granite e7 wont build air. I installed new
2005 mack granite e7 wont build air. I installed new compressor, new govner, new air dryer. Will not build air at idle. Air lines are not kinked. No regulators going into tanks. … read more
Bradey V
Bradey V
Certificate
When I am going dow the road. I am having problem with air
When I am going dow the road. I am having problem with air pressure at 102 to 105 psi on primary tank. 105 to 110 on secondary tank.… read more
Wayne
Wayne
Journeyman
Vocational, Technical or Trade Scho
5,115 satisfied customers
I have a air pressure problem on my Mac truck. It does not
I have a air pressure problem on my Mac truck. It does not generate enough air pressure on the primary side there is a 40 pound difference between the primary and secondary and when we work the truck … read more
Mike Mcmillan
Mike Mcmillan
Triage Tech/Shop Foreman
Associates
561 satisfied customers
KW T-660 2010 secondary air pressure gauge is reading 150
KW T-660 2010 secondary air pressure gauge is reading 150 psi while primary is at 110-115 as usual. I pumped brakes down to zero psi on primary and secondary gauge read about 50 psi. Is my secondary p… read more
Wayne
Wayne
Journeyman
Vocational, Technical or Trade Scho
5,115 satisfied customers
Freightliner Columbia 2010 with Detroit Series 60 Air drier
Freightliner Columbia 2010 with Detroit Series 60 Air drier assembly and air governor have both been replaced twice. Both primary and secondary air gauges going to 150 psi Air from air drier purges fo… read more
Mike Mcmillan
Mike Mcmillan
Triage Tech/Shop Foreman
Associates
561 satisfied customers
Working on a 2007 Freightliner Columbia with Series 60 Detroit.
Working on a 2007 Freightliner Columbia with Series 60 Detroit. Builds air very slow and wont purge from new drier. Will build to about sixty psi at idle then when reved to around 800 RPM will build t… read more
Daniel Wilson
Daniel Wilson
Auto Mechanics 1&2/diesel mech
14,356 satisfied customers
Im having a problem building air pressure. It will not get
Hey im having a problem building air pressure. It will not get about 30psi. I changed d2 governor and still no pressure. Has s code 6H 164. Can u please help me … read more
Daniel Wilson
Daniel Wilson
Auto Mechanics 1&2/diesel mech
14,356 satisfied customers
I have 2010 Freightliner cadcadia dd15 , having problems with
I have 2010 Freightliner cadcadia dd15 , having problems with air not building up, secondary usually builds first , dryer pops Off when secondary air builds up, replaced dryer , check valve on 3rd tan… read more
Daniel Wilson
Daniel Wilson
Auto Mechanics 1&2/diesel mech
14,356 satisfied customers
My air brakes pump up to 135 psi but when I release park brakes
My air brakes pump up to 135 psi but when I release park brakes and supply air to trailer the psi drops to 100psi and does not build backup to 135psi unless I shut it down and drain air tank then it b… read more
Travis A. Wells
Travis A. Wells
Truck Mechanic
Associates of Applied Science
15 satisfied customers
air is slow to air up. not sure how to check the unloading
air is slow to air up. not sure how to check the unloading valves or the governor. There doesn't seem to be any air leak. I can't hear anything. But I know that there is a way to test between the gove… read more
spankyjr1
spankyjr1
Retired
Vocational, Technical or Trade Scho
420 satisfied customers
I have a 2003 International 9200i tandem semi tractor. When
I have a 2003 International 9200i tandem semi tractor. When the truck is running it loses about 5psi per minute secondary air and the air compressor will not load until the secondary air reaches appor… read more
Wayne
Wayne
Journeyman
Vocational, Technical or Trade Scho
5,115 satisfied customers
The air pressure on my Mack CX613 is ranging from 150 psi at
The air pressure on my Mack CX613 is ranging from 150 psi at times then it will drop below 70 and will not build air pressure until I bleed the air down to 20 psi. After I bleed the air down to 20 psi… read more
Wayne
Wayne
Journeyman
Vocational, Technical or Trade Scho
5,115 satisfied customers
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Daniel Wilson

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Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.

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