Mewesley91

I have a 1997 Ford F150 4x4 and when I take my foot off the accelerator after going about 55-65 mph there's the grinding sound that gets worse\louder as it slows down. As I'm about fulling stopped, something pops and it sounds like it has popped back into place. This jerks the truck and it stops grinding. It will not make this sound while my foot is on the accelerator and it does it everytime I try to slow down. Does anybody have any idea what this might be?

13Harleyfan

Check your driveline, sounds like something worn and when you take the load off(acceleration) it unloads the driveshaft and it allows whatever is worn to make noise while the rear wheels put the load on the drivetrain.

Greenthunder

This has happened twice in my 07.. It felt to me as i was going about 60 mph.. it felt like the 4x4 slipped in to gear and was trying to catch up.. after i slowed down to right around 20 mph it the horrible grinding stopped and there was a click where 4x4 engages for the first time.. This happened about a month ago.. Hopefully it will not happen again..

foosefan

My 08 f150 4x4 has developed a driver side clunk. I went to a garage and they told me it was my upper ball joint. Dont think it is because it does it on throttle not over bumps. And its now developed a grinding noise(driver side) while in motion. Im not mechanicaly inclined and dont have much of an idea what it could be

Greenthunder

update! So this last winter I had to fix a part on my 4x4 drive. They said it was the solenoid. When it snowed I didn't have 4high or 4low. If I did have 4hi it went in and out. I am guessing over the last summer when I was pulling my inline trailer (moving the winter toys around!) and it must have kicked in to 4hi at 55 mph. So I am not sure if this helps anyone but I havent had any problems since I had this fixed!

97FordBoy

i realize thsi is an old post of yours. but i suggest checking your front cv shafts. sounds like one is worn and moving about freely