I replaced my brakes about a month ago, and my IWE's and my IWE solenoid. My drivers side IWE was destroyed, I have the 2004 lariat, so i have the uncovered stock solenoid, and opted to purchase the one with the cover.

I still have the low vacuum leak rattle, so I pulled the hoses off the other day and check one hub at the time, and I have no vacuum leak at the system, it's holds 23 PSI, so i'm thinking I should have replaced my hubs as well, my truck has 117,000 miles.

IS there a visual inspection I can do on the hubs before I order new ones? Or am I just gonna have to order them, and hope it's the problem....I recall looking at them closely, and they looked great....

izzy

 

I had a similar issue. I replaced my IWE solenoid and had my truck vacuum tested. It turned out that I didn't have any leaks in my system and my IWE solenoid was working properly.
I took my truck to a ford mechanic and he simply raised the truck up on a lift and removed the vacuum tubing by the hubs, spun the wheels a few times and a ton of rust blew out of the hubs. Since then my issue has been corrected.

 

Sometimes it's the simplest of remedies that work so well!

Chalk one up for the local Ford mechanic!

 

I'm so gonna try that! You guys are AMAZING on this forum!

Izzy!

 

So the other day, I tried Maniac01's suggestion, of removing the IWE vac. lines, and spinning the wheels, I tried a couple of times. Sadly, it didn't resolve the low vacuum shutter that I hear in the IWE's, I checked the vacuum again, and there is no leak off, they hold well, so I took a piece of vaccum line and removed the lines from the engine to the solenoid, and hooked the top and bottom together, to bypass the solenoid. The rattle still occoured, but it didnt' seem as loud. It's worth mentioning, this vacuum line was rather long, it's from my vacuum pump kit, and i used the plastic fittings to make the lines fit snuggly. I'm kinda lost on this....lol! It could be the hubs, or could be that solenoid, it's a new solenoid, but we all have purchased poor parts in the past, what do you think?

izzy

 

Ok, first, let me say, I AM AN IDIOT! I hadn't read the ALL the information that was availiable on this thread, so for that, I smack myself

But, I digress. So, yesterday, I printed it out, went home after work, and checked all the lines, there were no leaks. The vacuum box, didnt' leak. BUT, the check valves, both, after 118,000 miles, had failed. SO, I called Ford, and shocker, the parts guy said he had no idea what I was talking about, so I drove to an autparts store, and walked into the HELP section. There, on the shelf, amid a bright light, were two check valves. After two check valves and 10 dollars in parts to make them fit, my IWE system has stopped making the low vacuum noise, and for that, I thank you....

 

nice explanation, subscribing!

 

Excellent Izzy! Likely saved enough for a dinner out!

 

My issue started out making noise only when real cold it went away though. Now when I lock my truck in 4x4 and put a load on it there is a grinding sound coming from the passenger side, which doesn't spin at all, and the driver side makes no noise what so ever but also doesn't spin... Can someone help me narrow down exactly what can cause this?

 

Much like a rear axle with open differential and one wheel on ice or jacked up ...
... if one IWE fails to engage fully and instead the splines slide across each other making that racket, there will be no power transmitted to either front wheel even though the other IWE engaghes ...
... unless you have a locker differential in front which I doubt.

Sounds like you have a IWE that's not engaging for some reason.

 

So I'm having a grinding noise coming from the right front for about a month now. It sounds like fine splines grinding to me but anyway... I can be driving along and it will just start this wild grinding sound all of a sudden. The thing is, I can engage 4wd and it completely goes away. Disengage and sometimes the noise comes back, sometimes it waits a bit. Is this the same kind of thing you guys are talking about? I'm totally at a loss on this one and my dad which has been a mechanic for 40+ is out to lunch on it too. I'm hoping it's nothing major but if it is I need to get it taken care of ASAP before it causes other problems. What's bad is with the "quiet steel" that these trucks were built with, if I can hear the noise as good as I can in the cab I can only imagine what it sounds like outside. Makes me cringe... Btw, '04 SCrew, 5.4, 145k.

 

So would it be just that seal? If its just one what would cause just one ? Help me narrow it down.

 

The rerason this is happening is that the whole IWE system depends on vacuum. At rest (no vacuum), your IWE's are actually locked. Start the truck up - or put it in 4WD - and the system applies vacuum to the IEW's and disengages them.

Now to your point. You either have (or had) a vacuum leak someplace or an IWE go bad in the past. What's happening now is that it's partially disengaged and thus the grinding noise. It may be a bad Solenoid, Vacuum Line or Check Valve that caused it and you need to track it down. But, since your IWE has been partially disengaged for so long, it's probably bad too.

Hope that helps.

 

Its just one side.

When this first started happening one side of the truck would whine when it got really cold out. It didn't happen all the time only after the truck sit in the cold weather. It would make a whining/ grinding noise. It would go away. Now my truck when I put it in 4x4 and put strain on it, it just grinds and my front wheels do nothing.

If it were a vacuum check valve wouldn't it cause both sides to mess up? It has to be right around that side correct?

 

Not at all unusual to have just one side go. That's what happened to my 2005. And remember, once you zing an IWE for long enough due to a vacuum (or should I say lack of vacuum) problem, it's toast and needs to be replaced. That grinding you hear is an IWE getting ground up.