Start and stop thud

The vehicle is a 2000 Ford Ranger 4.0 liter automatic transmission.



I feel a slight to moderate (thud, jerk, or jolt) like feeling after I reach a complete stop and right when I start from a standing stop. I do not feel it at a non-complete rolling stop. Also, I’ve rolled to a stop without hitting the brakes and as-soon-as the truck stops the thud feeling hits. So I’ve ruled out the brakes as the problem. The truck has no problems shifting and overall the shifting is very smooth.



I?m concerned that this issue, if let go, may grow into something major.

How many miles? It sounds like it might be worn U-joints.

I appreciate your reply.

It has 82,000 miles. But I am the recent second owner so I can only vouch for a small number of them. I feel comfortable based on the carfax report and the overall condition, 82,000 miles is about right. Not sure if it matters but it does have 4WD.

If it is U-joints, how much do u-joints replacement typically run and is this something that a DYI could do? My DYI level is brake replacement (rotors and pads), but I like to take on new challenges.

GreggW3g

One thing to check for this noise are worn lower ball joints. And it’s easy to do.

Place a floor jack under the lower control arm of the ball joint in question. Raise the vehicle until the front tire is 5"-6" off the floor. Place one end of a 6’ long 2X4 under the tire. While someone looks under the vehicle with a flashlight at the ball joint, lift up on the bottom of tire and release. If the ball joint is worn, it’ll be seen moving up and down in it’s socket.

Tester

Look for loose or warn bushings in suspension and on shocks and struts.

Also take a close look at the mounts - if you had one that was broken you should feel all sorts of bad things while driving. But I once had someone leave one loose after doing some work and what you described is pretty close to what my car did with a loose mount.

Loose mounts was my original thought, but I do not exprience any bad things except at the initial start and at the complete start.

FYI - I didn’t have anything but the noise either - I literally got a clunk when starting off presumably as the engine twisted from torque, and then a clunk back when braking presumably as the momentum shifted it back forward. Other than the noise I’d not have noticed anything.

My first thought was ujoint, Do you get the clunk while shifting with your foot on the brake from forward to reverse? But that is why one takes a car to a qualified mechanic to perform a repair if you cannot do it yourself. The ideal mechanic will analyze fix what is wrong. Problems tend to get worse over time not better.

Tester, thanks for your input. I did not suspect ball joints because I do not hear any noise. Also, when hitting bumps or turning corners there is no noticeable klunk sound. I had ball joints go bad on my mini van some years back and I recall the clunk noise when hitting bumps.

I just got back from taking the truck around the block. I focused on coming to a complete rolling stop without using the break then taking off. No break was used. When I get to the stop, slight tug or grab feeling (no sound). Similar when taking off. Never touched the break in the process. Understand I’m rolling along at 1 mph waiting it to reach a complete stop. It finally stopsfollowed by the jolt, grab, or tug feeling.

I’m on this forum because I took it to a qualified mechanic. His diagnosis was the idle air control valve needed replaced. One new idle air control valve later and problem is still there.

I appreciate everyones input/feedback and hope to keep getting more.

Had a 03 Ranger with the 3.0 V6. It would clunk rather unpredictably from the front. Usually on braking. Turned out to be a motor mount.

I agree. It sounds like a motor mount.

Did you figure out what the problem was? I have a 2011 Chevy Silverado with 115k on it and it’s doing the same thing can’t find any answers