Hawk 1

My 05 screw lariat will not go in 4 wheel drive when the temperature drops to below 32 degrees. Some say I have water in the vacumn lines and freezing up the IWE. Anybody know how to get the water out of these vacumn lines?

fol4321

I'd disconnect the vac lines at both ends and blow some air through yhem. Nitrogen would be better but you probably don't have that

Hawk 1

I'll try that but isn't there a check valve in there somewhere? unhook at the wheels and where would i put the air in at?

VTX1800N1

Make SURE you disconnect both check valves, the solenoid on the firewall, and the reservoir behind the battery before you apply any air pressure to the vacuum system, or you will destroy them.

If there is water in the IWEs, you have to remove them to get it out. Repack with lots of wheel bearing grease.

Hawk 1

Thanks VTX looks like I got a little work ahead of me. Will try what you suggest. Thanks again

sglover

Please correct me if I am wrong but the IWE'S themselves are not greaseable just the spindle and or hub splines. and your gonna have water in there its just a dust boot not waterproof is it?
The water must be in the IWE'S or they would loose vacum and stay locked in when the lines iced up. After a little driving and brkeing I would think it would warm up enough to melt the Ice, but being a Florida boy I dont have those issues. Just mud and beach sand. Good Luck.

VTX1800N1

Water can get in on either side of the vacuum seal and freeze the IWE up. It can get in on the vacuum side through a solenoid that admits water through the vacuum lines. To get rid of that water, the IWE would have to come off and be turned upside down to drain the water out the vacuum nipple. Water can get in the other side either through the hub seals, in between the axle and hub where that needle roller pilot bearing sits, through the seal on the circumference of the IWE that gets compressed to the hub as the IWE is bolted to the steering knuckle, and the seal between the half shaft and IWE opposite the steering knuckle side. The IWE has to come off and all the grease cleaned out and replaced to get rid of water there. Either way the IWE has to come off. In the first case, the water is internal to the IWE, in the second it's external.

I highly suggest applying liberal amounts of grease everywhere in the IWE/Hub interface and needle roller pilot bearing. Make sure to coat the half shaft to IWE and IWE to hub seals with grease to discourage water infiltration.

Further, water can be frozen in the vacuum lines themselves, which prevents vacuum from passing to the IWEs so that they remain locked even if the rest of the system is working properly. The IWEs don't have to be filled with water for this to happen- the vacuum lines are small enough in diameter that water can sit in them and not make it down to the IWE. No amount of driving will get enough heat in the vacuum lines in freezing weather to melt ice in certain places in the lines.


There should never be water in either side of the IWE. There are two vacuum lines to each IWE. One is for vacuum, the other is a vent that runs back up high in the engine compartment. If there is water in either side of the IWE, you have a problem that needs to be fixed.

sglover

Agree, with you for the most part but I didn't think you could get inside the IWE. I haven't replaced them just looks like a sealed unit. Now that I think about it I guess it's semi-wateright seal if it holds vacum but then again it constantly has vacum applied, when driven. So to me it would be useless to tare the unit down unless replacing the IWE'S. Maybe run some silicone in there to displace some of the water or use a vacum pump overnight and get the majority of moisture out.

VTX1800N1

Not talking about taking it apart. I don't think it's serviceable at all. I'm just talking about removing it and shaking the water out of the vacuum and vent holes.

sglover

Yea I got what your saying, just running over other options without the tare down, not like it's a big job though to take apart.