While driving, I noticed my truck started making a grinding/rattling/whining noise. I thought it was the axels or brakes. I changed all 4 brakes and the noise went a way. That turned out to be a coincidence. It came back a few weeks later. On a whim, I reached down and pulled it into 4 high and the noise went away. My truck is an automatic with a manual 4 wheel drive shifter. Every time I hear the noise, I pull it into 4 high and back to 2 high and the noise goes away. Does anyone have an idea of what the problem may be? I have a 2004 XL regular cab. Other than the noise, everything else is fine. I appreciate any help I can get on this.

 

its the IWE solenoids...very commonn on our trucks mine has acutally been replaced twice in one year. Its a vacuum leak in the 4x4 system causing it to want to engage.

 

Actually, if it's a 2004 or newer truck, it's IWE Solenoid (singular) because there's only one. It's located up on the passenger side firewall. Now for the bad news. If it goes bad and / or you have a vacuum leak, you pretty much tear up one or both IWEs. The good news is, if you're mechanically inclined at all, you can save a fortune on the repair. Do a search on this forum for TNF150's posts on the subject and you'll see what I mean.

 

yea man, i just got done replacing my hubs on my truck because my solenoid went bad and both my front hubs cracked....so the sound you are hearing are your hubs more than likely...hopefully its just the solenoid but if not, might be replacing your hubs...

 

Let me clarify. When the solenoid goes bad and / or when you have a vacuum leak, your IWEs only partially disengage. (In the absence of vacuum and / or when the truck is not running, your IWEs lock up.) When they start singing or grinding because they're only partially disengaged, they tear themselves up in pretty short order. So, a simple bad solenoid can take out one or more IWEs if given a little time.

Go for the solenoid first, then the IWEs if you need them.

 

Yes sorry about that but that was the point I was trying to get across...

 

They're all right. Vacuum lines. I found that most of my problems are located around the strut tower. I have a 2.5 AS lift, and that changed something, that causes me to have breaks. I don't think Phoenix heat helps the chintzy plastic tubes either. Can someone make a stainless kit, so we can get on with our lives?

 

Amen!

 

I replaced the IWE Vacuum Solenoid today on my lunch break. The part was just over 40$ and took me less than a minute to replace. I didn't even have to remove the battery. I drove 42 miles and the 4x4 did not try to engage at all. Normally, it would have tried 3 or 4 times. The truck even seems to shift smoother but I don't think this solenoid would have anything to do with that other than holding the IWE's back. Looks like this may have fixed it. I really appreciate everyone's help on this. Thank you.