Hello,

I have an 04 F150 (4.6, auto, 4x4, SCrew) with 300,000 miles. Anyone modify their existing 4X4 IWE actuators so they are always locked in?

My last set of actuators didn't last long My vacuum is too low under hard acceleration... Actuators partially engage leading to early failure.

I'd like to take an actuator apart, modify it so it's always locked in.

Thoughts? Some loss of mileage? Other ramifications?

good luck- jim

 

easy, cap the vacuum lines.. vacuum keeps them unlocked, not locked.

 

Have you checked the vacuum system for leaks, particularly the tank and the 3 check valves? The system is designed to compensate for low vacuum conditions, such as hard acceleration, and keep the IWE's disengaged. Engaging them permanantly would mean you'd be parasitically rotating the front differential, CV axles, and driveshaft.

 

Both actuators failed in less than a year. One is in the engaged position and one is in the disengaged position- no 4 wheel drive...

Tank looks good- haven't checked the check valves. Given it's age and sub-par condition, I'm more interested in a 'work-around' to the issue as opposed to putting new parts on it.

good luck -jim

 

Have you ever tried to drive a 4 x 4 locked in full time, on the highway or winding blacktop road ? Its like hearding elephants ........... FIX the vacuum leak and keep the IWE.

 

The system is easy to trouble shoot and fix. New vacuum lines and check valves are cheap. So is the solenoid if that's bad.


The most common failure is the original solenoids. Cracked/leaking vacuum lines are next (these can also allow moisture into the system, and more problems). Then check valves. Any of these can/will cause intermittent partial IWE engagement, and eventual failure of same. Once in a blue moon an internal spring might fail in an IWE, which might cause the IWE to fail stuck open or closed.

 

You can simply disconnect the vac lines and they will engage and stay engaged forever ....and drive the truck in 2WD on the street and still switch to 4WD Hi or 4WD Lo as desired on slick surfaces.

Them Harley trucks have IWEs that just stay locked as I recall, vac lines capped. Their TC is different so they are full time 4WD .... it allows some difference in frt and rr drive shaft speeds ..... which your truck doesn't do ..... so just make sure in 2WD on dry roads ..... like you do anyway.