Vacuum leak for auto hubs

[dboyw]

Hello. I have read many post in regards to "fixing" the auto hubs that do not engage. I did try the one fix about trimming an inch or so off the end but it did not help. I read somewhere where the size of the line is but I forget it my, didn't bookmark or write it down. Could you tell me?

I did do the test, had the air on and engaged the auto 4x4 and it did go to the defrost setting, so I know there is a leak somewhere.

Beside the lines to the hubs, where else is a good place to look?

How easy just to replace all the vacuum lines for the hubs?

Sorry for all the questions, just a few I needed clarification on.

Thanks.

 

[threejacks]

Take a look at these stainless steel wrapped lines.

http://www.dieselsite.com/index.asp?PageAction=VIEWPROD&ProdID=348

 

[HTRDDSL]

Man am I ever glad I came to this site. You may have solved my problem with the auto hubs as well. They just started acting up. Works great in manual mode but will not lock up with the switch.

 

[CHPMustang]

First place I check is if I kicked the vacuum hose assembly off the heater airbox motor front area behind the dash.

After that I chase down the lines going to the hubs then off to the vacumm pump and lines connected to it.

 

[HTRDDSL]

Thanks for the advice. That will be my project tomorrow.

 

[HTRDDSL]

I followed your advice and it is definitely a vacuum leak. But I wasn't able to find it. I have another go at it tomorrow.

 

[HCAbowman]

Hope ya find it!! That reminds me, I need to check mine...

 

[HTRDDSL]

I have a vacuum tester. Is there any special way to remove the line from the opposite end to the hub. Where it connects at the chassis.

 

[Doggy Daddy]

It seems to me that I have heard of the solenoid itself leaking vacuum. I think that if you turn the key on without running the engine the vacuum pump will run and you can possibly hear the vacuum hissing.

 

[dboyw]

Not that I mind my thread being hijacked , I did find the answers and fix I needed.

I took a small piece of the hose from the truck to the hubs to the parts store and bought four feet of the hose. Came home, cut it in two and removed the old and in with the new. Started the truck, turned the vent on, then switched to 4x4. At one point I did feel the air move from the vent to the defrost but it came back and stayed. Hopefully that is it.

Good luck HTRDDSL with your hunt.