Ford F-150 Raptor 4WD IWE Vacuum System Grinding Issue

The Ford F-150 IWE vacuum issue with the 4WD system is a visceral experience that will make you think twice about going off road.

Ford F-150 Raptor 4WD IWE Vacuum System Grinding Issue
Screenshot Credit: Ford Motor TSB Diagram

While recently vacationing in Colorado, our 2019 Ford F-150 Raptor truck started making a horrific metallic grinding noise. The noise would intermittently appear when driving in two-wheel drive on the highway around 30-60mph.

We would sometimes hear this noise 3-4 times in one hour, and on other stretches of highway we would not hear it for over two hours. It was very perplexing, and it left us with little confidence in the truck, considering this was our ride home back to Texas.

After doing some research online, we narrowed the issue down to the IWE valve that holds the front hubs open while you're driving in 2WD. The way the 4WD system works on a Ford F-150 is the front hubs that engage your 4WD are held open using a vacuum system.

This vacuum system will release the hubs, so they engage when you put the truck in 4WD. What was happening with our truck was the hubs were partially engaging, causing a metallic grinding noise that will make your heart drop.

The Truck

2019 Ford F-150 Raptor Truck
2019 Ford F-150 Raptor Truck
  • 2019 Ford F-150 Raptor
  • 31,000 miles
  • Oct. 2022 is when we had the issue
  • We were about 1,500 miles from home

How Bad Does the Noise Sound?


Ford F-150 Raptor 4WD IWE Vacuum System Grinding Issue

It sounds horrible. Personally, I have never heard a sound like this come from the powertrain of a vehicle. I’m sure it happens, but it’s not something I have ever experienced. At one point, we heard severe grinding and then a loud thud.

This happened twice in a row while I was driving the truck. The sound was visceral, and it felt like something had fallen off the truck and was lying in the middle of the road.

Video of the IWE Intermittent Grinding Noise

Here is a short video of the grinding noise we captured coming from the front 4WD hubs trying to partially engage while we are driving down the road. While this video demonstrates some of the noise we were hearing, there were other times when the noise was more severe depending on the speed we were driving.

How Did We Get Home?

To eliminate the severe grinding, we unplugged the IWE valve under the hood while the truck was in 2WD. This was a tip we found online by other Ford F-150 owners having the same issue. Whether this is a good idea is a question for a Ford engineer. It worked great for us on our 14+ hour drive home, as we did not hear the noise once.

The good news is if you do experience this issue with your Ford F-150, it most likely won’t leave you stranded. At least, we have not read anywhere online where it has left someone on the side of the road.

What Was Covered Under Warranty?

Much to our surprise, everything was covered under warranty. I don’t know if this was because we still had some of our powertrain warranty left on the vehicle, or if Ford is taking ownership of the problem.

When we first arrived at our local Ford dealer, the service adviser scanned our VIN, and immediately he found a Ford TSB that addressed our issue. He said Ford was aware of the issue, and they will cover all expenses, even if that includes replacing the front hubs.

After having the truck a few days, we were informed by the service adviser that they are replacing the front hubs on the truck that activate the 4WD system. The heaving grinding noise we did hear had damaged the splines on the gears, therefore warranting replacement. We were glad to hear this, especially after the several loud thuds we heard while driving.

Should You Get an Extended Warranty?

I am not a fan of extended warranties on anything. It seems everywhere you go today, someone is trying to get you to purchase an additional warranty, even it's something small like a hammer from your local hardware store.

Due to the complexity of vehicles today with the myriad of sensors, electronics, and the rush to market by manufacturers, I would say an extended warranty might not be a bad thing on a vehicle. Especially if you plan to keep the vehicle long term, and can get a reasonable price on one.

We also own a 2015 Lincoln Navigator, which is essentially a Ford Expedition. With just over 80K miles, we were just informed it needs a new $7,000 transmission. The vehicle started having a bad vibration at around 60MPH, and it would act as if it were losing power.

After putting a code scanner on the vehicle, we were showing misfires on cylinders 4 & 6. Our first thought was the vehicle is having coil issues because we had this problem around 30K when we first purchased it certified used from the Lincoln dealer. It certainly would be nice to only have to pay the deductible on an extended warranty.


If you are experiencing this issue with your Ford F-150, you're probably pretty freaked out right now. The metallic grinding noise that comes from underneath the vehicle can be shocking, and most people around you will hear it as well. I know our truck turned a few heads while driving through a few small towns in Colorado.

The good news is Ford is taking ownership of the issue unquestionably on vehicles within their power train warranty. If you no longer have warranty on your vehicle, you might get Ford to help out with the repair since it is a known issue. Like Irvin Lindner always says, it never hurts to ask.