How To Weak Vacuum Line and grinding noise FIX

[BIGt0007]

Thanks for the tips
I just pulled and capped line from air actuator so now IWEs are locked all the time. I say keep it simple and go back to manual hubs......never had a problem on my old mans 89 lariat F150...that truck took a beating, plowin all winter and mudin all summer.

 

[tlestrange]

Front end rattle

Hi,
I have a 2010 F150 STX and am experiencing what sounds like the exact same problem. Runs fine in 4 wheel drive rattles in 2 wheel, but only when accelerating. My question is since I have to manually shift into 4 wheel drive is the system still vacuum operated?
Thanks in advance,
Tim

 

[Mil T]

Hi,
I have a 2010 F150 STX and am experiencing what sounds like the exact same problem. Runs fine in 4 wheel drive rattles in 2 wheel, but only when accelerating. My question is since I have to manually shift into 4 wheel drive is the system still vacuum operated?
Thanks in advance,
Tim

Yes. Same system as the Raptor.

 

[tlestrange]

Front end rattle

Thanks Mil T

I have since found and corrected the problem. There was a cut in the vacuum line that goes across the beam between the front wheels. The thing is I still get an occasional, very slight, rattle every once in a while. Nothing like before the repair but still something. Do you know if this could be the result of damage that was done when the line was broken? Should I be concerned?
Thanks,
Tim

 

[MatMan]

Thanks Mil T

I have since found and corrected the problem. There was a cut in the vacuum line that goes across the beam between the front wheels. The thing is I still get an occasional, very slight, rattle every once in a while. Nothing like before the repair but still something. Do you know if this could be the result of damage that was done when the line was broken? Should I be concerned?
Thanks,
Tim

I just re read the thread in detail and the bottom line is that when you have a vacuum leak, you potentially damage the actuator which may cause another leak or a new noise sound (purr, cards in spokes) and possible damage which requires a detailed tear down inspection to know for sure.

Now go tear that shit apart.

 

[Mil T]

Thanks Mil T

I have since found and corrected the problem. There was a cut in the vacuum line that goes across the beam between the front wheels. The thing is I still get an occasional, very slight, rattle every once in a while. Nothing like before the repair but still something. Do you know if this could be the result of damage that was done when the line was broken? Should I be concerned?
Thanks,
Tim

One of the main concerns is the difference between a crack in the line and an actual break in the line. If it is cracked then you could still pull vacuum but not enough to completely disengage the IWE which will cause the noise. If it is completely broken then it should default into 4 wheel engaging the IWE. It does not mean it is in 4 wheel drive until you actually shift it to 4 wheel drive in the transfer case. Only that the iwe is engaged. If you found one crack then there could be others. The best way to check it is to take the vacuum line off at the brake booster that feeds the entire system. Put a vacuum pump on it and pump it up to 15-20 lbs and let it sit. If it leaks down at all then you have a leak in the vacuum line somewhere. If it is holding then you probably don't have a V leak in the line.

 

[Big22Dubz]

I'm literally having the same grinding issue. 2011 60k miles. Dealer is saying to replace transfer case for $2100. Ran the vacuum line idea by the service advisor and he told me otherwise.

 

[Mil T]

I'm literally having the same grinding issue. 2011 60k miles. Dealer is saying to replace transfer case for $2100. Ran the vacuum line idea by the service advisor and he told me otherwise.

There's an easy way to check it by putting vacuum on the vacuum line and see if it leaks down. If it leaks down then you have a leak and that is probably your noise. Is your truck out of warranty? Do you use 4 wheel drive a lot? What is he saying the noise is? Transfer case is controlled by knob. Are you hearing the noise in 4 wheel drive when transfer case is engaged and not in 2 wheel drive? I doubt very seriously that the transfer case is a problem and you should look for another dealer. By the way. It's the service advisor. Not the mechanic. Follow my instructions and do the vacuum line trick or disconnect the vacuum line at the brake booster completely and see if the noise goes away.

 

[FordService]

I'm literally having the same grinding issue. 2011 60k miles. Dealer is saying to replace transfer case for $2100. Ran the vacuum line idea by the service advisor and he told me otherwise.

Hi Big22Dubz,

Are you planning on proceeding with the repair at your dealership? If so, I'd like to look into some options to assist. For me to do so, I'll need a PM from you with your full name, best daytime phone number, VIN, current mileage, and servicing dealership. I'll get to work.

Crystal

 

[Gilligan]

The grinding noise on my truck turned into a jack hammer earlier so I had it towed to the dealer. I'll post updates if it seems like this issue was the cause.