Q: My car shakes when I decelerate on the highway.

Hey there.

Thanks for writing in today in regards to your 2004 Jeep Grand Cherokee. I think the issue you’re describing is not related to the differential. Most of the time, a vehicle shakes because of three specific items; problems with the tires or wheels, loose or broken suspension components, wheel bearings that are worn out. With a four wheel drive Jeep Grand Cherokee, the first thing I’d dive into would be CV joints being extremely worn out, or the tie rod end joints.

When you decelerate, weight is transferred to the front end of your Jeep quickly; even without pressing the brakes. That causes more load to those suspension components and can cause the shaking you’re describing at the speeds you’re indicating. The best bet here is to contact a local ASE certified mechanic, such as one from YourMechanic, and allow them to road test your Jeep Grand Cherokee. The road test is often the best starting point to accurately diagnose the shaking you’re experiencing.