OK. I have a 2003 5.9L with Auto tranny. Behind the passenger side battery is the vacuum pump to provide vacuum to the cruise control. Im not sure on how to test and under what conditions but here is what I have done. I dont have a vacuum tester, should I be able to feel vacuum with the lines disconnected and cruise control turned on?

Here is what I have done. Turned truck on, turned CC on with vacuum disconnected, I cant feel any vacuum with my finger over the output. Is 10 inches of mercury detectable without a tester?

 

10 inches of mercury is equal to 5 psi and you should be able to feel it.

Not sure that the pump will run below 35mph.

 

Thats whatt I thought. But should you have vacuum there as soon as you turn the CC on or does the vehicle have to be up to speed? The only electrical connections I can see on the pump aer just power going in, there are no control lines telling it to turn on or off.

 

OK. The Vacuum pump is toast by the looks of it. 12Vdc at teh plug going in as soon as the key turns on. Opened the pump up and it even smells like burnt wiring.

Problem: The dealer here in Canada wants $296 for a new one. No wreckers have parts, the US Dodge dealer in Plattsburgh, NY wants $228.

I saw a thread where someone said you can get them a lot cheaper but I have nmot even been able to find anywhere that carries this other than the dealer. Does anyone have any places they know of to get this?

 

OK. Im spamming the forum by replying to my own thread too much. Sorry. Just found a replacement for this. Like I said the pump in Canada is almost $300 in NY $230 at the Dodge dealers.

I frequent Plattsburgh NY a lot, so I looked up autozone and typed in vacuum pump in their search. Low and behold they carry an identical model but its listed for a Ford http://www.autozone.com/autozone/acc...ier=11359_0_0_

Autozone was nice enough to put in the text description of the item that it was a Dorman vacuum pump so I looked up Dorman and come to find out this pump with autozone part number 914-204 is used in both Ford and Dodge diesels, http://www.dormanproducts.com/c-745-vacuum-pumps.aspx

If you dont want to get ripped off by your local dealer theres a little info on where to get the pump when it dies.

P.S. to all those that say we dont have a vacuum pump on these diesels, 03 diesel with an auto tranny uses this electric pump to create vacuum for the cruise control. Manual is electronically controlled and Im gonna guess a gasser is as well.

 

I just picked up my 03 3500 srw 5.9 auto and the cruise is intermittent. It may work for a while, but then it just kicks out. This is GREAT info!!! Thanks for posting it. I am gonna check mine out and I hope that is all it is...

 

Why in the world would a truck company put an expensive vacuum pump into their diesel trucks to operate cruise control, when electric cruise control servos are cheap and plentiful? Don't they even WANT to out-price the competition???