About 2 years ago had the ice in blender noise in front wheel of vehicle. After reading up I changed 4wd Solenoid with the one with the water shield and everything was great. Now again I have a slight grinding, nothing like it was before, but again If I put it in 4wd it goes away. normally happpens at about 30 mph but does not clunk like it did before when you came to a stop. Could it be my solenoid again. Pulled vacuum lines and could not feel and cracks. any tips what how to check vacuum lines without vacuum tester?? Trying to fix myself so I do not have the crazy bill from the dealer? Thanks

 

A mighty vac hand vac pump which has a gage and all sorts of hoses and attachments is a great tool for checking these things. If you had one you could pull the hose at the solinoid and pump up the system and watch for how fast she bleeds off. You can check each IWE seperately. You can do all kinds of stuff with them, like even bleed brakes.

You have any friends that can loan you one?

 

Borrow one or see if you can "rent" one...buying one is still cheaper than the diagnostic fee at a dealer.

 

If you have a slight grinding that goes away in 4wd it really sounds like you have a vacuum leak somewhere or possibly a bad IWE.

I would not continue to drive with the grinding. You can disconnect the line from the motor to the solenoid (just make sure you plug the line to the motor so nothing gets sucked in) and let the hubs engage. It will not be in 4wd since the transfer case is off unless you turn the 4wd switch in the cab.

I ran like that for about a month once until I could figure out my problem.

 

Thanks guys new to most of this vacuum stuff, but found some real useful info from this forum. I guess I am buying or seeing if any of my budies have a vacuum tester. Thanks for all the advice hope I can figure it out.

 

Incase you haven't read this one yet>>> https://www.f150online.com/forums/20...then-some.html

 

if you have a auto zone near you...they have those hand vacum pumps with a gauge for around 20 bucks....think that's what I paid for mine...very handy tool...

 

There are two check valves, one by your silonoid you replaced and one not far from that toward the motor. Take em off and check em, they are one way valves

 

Well I rented one and it looks like my passenfer IWE is shot when pumped up the axle still spins, but the driver side which is where the noise sounds like where it is coming from works like I think it is supposed to?? (jacked up front end) apply vaccuum to big side of IWE and the wheel spins freely without engaging the axle or half shaft not sure what you call it. does this sound right to anyone? Maybe just replace passenger side IWE and be good to go? Any thoughts for me.

Jeff

 

Just one more thing the passenger side will not hold vacuum like the drive side if that helps. Both test where done directly on the IWE. Thanks Jeff

 

Remember, vacuum unlocks the IWEs - which is exactly the opposite of what most people think. So when you start your truck and generate vacuum, the IWEs release. When no vacuum is applied, they lock up. So when you have a vacuum leak or a failing solenoid, they only partially unlock.

Does that make more sense?

 

That was what I thought. That is why when I put the vacuum pump directly to the IWE actuator and the one would not hold vacuum and also would still rotate the half shaft that the Iwe is locked and has a leak in it causing it not to disengage.

 

Well just replaced actuator and everything looked great, but now the sound is back and I can not even get the IWE to disengage when hooked up to a manual vacuum pump (it did when I first installed it) Could I installed it incorrectly? Any advice would be appreciated.

 

You'll need to replace the hub, probably. Stealer wanted 300 for a new one, but Autozone had Moog unit for 212. Takes a whopping 45 minutes to change if you go slow. After doing some grinding, the hub gear is usually wasted anyway and all the filings need to be cleaned out of hub area. Easier to bite bullet and change it. Steer clear of the cheap knockoffs from the other side of the Pacific. Heard bad stories of them not lasting too long. The Moog is a good quality, solid unit and believe they make the FoMoCo OEM unit. (PS: Moog makes the "National" brand white box unit, too, which is a few bucks cheaper than the Moog labeled box.)

 

The only thing I can think of is that you had a good amount of metal filings in the area from the IWE that went bad. If you don't clean everything out properly, things can hang up. Last time I checked, there really wasn't a way to install an IWE incorrectly. Given that it isn't really that bad of a job to open everything back up, you might want to cinsider going back in and checking everything. I'd also consider hooking the vacuum pump to the IWE all by itself to see if the IWE might actually be bad. Check for burrs on the splined shaft too.