2 inch leveling kit issues in 4wd?
 

Hey guys,

I'm new to the forum. and got my first question. I have a 2010 F-150 STX with 122K miles that I recently put a 2 inch RBP leveling kit on. I work in the mining industry so this truck sees heavy 4wd use everyday off-road in rough muddy terrain. Since the day I had this kit installed I've been hearing a grinding sound coming from the front end. So far (in the month that this kits been on), I've went through 2 actuator sets and a new set of front axles. Most mechanics I'm talking to are telling me that the kit is putting to much pitch on the cv joints and that's why I'm blowing out axles constantly. I've also double checked the vacuum actuators and solenoid, all which seem to be working properly. I'm kind of at a loss as to what to do next? I have never heard of a leveling kit causing axle failure on similar age F-150s, and I'm surprised I'm even having this issue. Any thoughts or help would be appreciated!

Thanks!

If the actuators (IWE's) are good and the vacuum plumbing is sound, replace the solenoid. It's a common failure item. The replacement sol. should have a little rain hood built into it. What brand of half-shafts are you using? Some of the aftermarket shafts don't have the articulation range of the OEM and fail prematurely in lifted applications. Unfortunately the OEM's are very expensive.

Did you get an alignment after you installed the level?

I replaced the solenoid yesterday and checked the vacuum pressure in the lines which are not torn. Still have the grinding. Also the axles are auto part international.

See attached pictures
https://cimg9.ibsrv.net/gimg/www.f15...aa37674f55.jpg

https://cimg4.ibsrv.net/gimg/www.f15...13800173fd.jpg
https://cimg5.ibsrv.net/gimg/www.f15...571614c341.jpg

Appears you've replaced everything but the vacuum check valve, the most common part failure. When does it grind? Are you accelerating even slightly, like going up a hill/incline? By throwing into 4X4 does the grinding stop? Are you sure the tech replacing the IWEs properly replaced them?

The check valve was also replaced. My procedure is, I come to a stop on level ground and then lock it into 4wd and then slowly start to accelerate. The truck locks into 4 but then as soon as I start moving I hear the grinding. I can be on level pavement and it still grinds

Could be a wheelbearing, I see tons of mud under there.
You could still be having IWE trouble. What brand are being used, Dorman are garbage, use OEM. Let's try something, pull the electrical connector off the solenoid. That will vent off vacuum, and the IWEs should engage. It's OK to drive it like that as long as you don't put it in 4H/4L. Does it still grind?
I'm thinking that when the IWEs were replaced, they weren't properly installed. It's very important to make sure they are engaged, or pull a vacuum on them to ensure they are pulled out all the way, BEFORE the spindle nut is tightened, or the teeth could be broken, not letting them engage and just turning/grinding.
Why were the halfshafts replaced?

There is no need to stop your truck to shift into 4H.. it's a shift on the fly (SOTF) system. you can select 4H at speeds up to 55 MPH. Remember ... vacuum holds the IWE's in the dis-engaged position .. when in 4WD the vacuum is vented allowing the wheel ends to engage.. check the vent lines .. the can get clogged

I have doorman's! I will request oem and find out how their installing them today. It doesn't grind at all in 2wd. This only happens in 4.