I have an '06 F150 that has a loud popping noise coming from the back end somewhere. It has gotten progressively worse, and is on both sides. When I put it in reverse it is the worst, but it also happens when I start to go forward. It doesnt happen when I am driving, just when I am starting to back up or go forward, usually over an incline (like backing out of the driveway). It also is at both sides (two "pops" depending on where the most pressure or angle is). Any ideas?

Perhaps what might be that what you are hearing is the brake pads taking a rearward "set" due to the rotor turning opposite the normal direction of rotation. I've seen this happen on some other vehicles.

I think your U joint is going out. My roommate's went out and it did some popping when changing directions.

i would think a u-joint would make more of a "clunk" or "clang" noise. if it were bad it would make noise when you put it into gear, also, i would think.

do the f150s have rear discs?

F150s have rear discs. unlikely for a 06 F150 to have a bad U joint, but it would be VERY obvious if it did.

You'd have squeaks, clunks, driveline vibration etc.

Could have blown out the carrier gear in the differential. I recently had similar problem on a GMC Sierra, except it popped when I turned.

I had a u-joint go out on a '95 Z-71 and it sounded similar to this. However, I agree that it would be strange for a u-joint to go out on an '06 model truck.

Next guess would be muffler bearings.

U joints will make a "ping" type noise when changing direction and they are going out...I agree with examining the rear end and the rear brakes.

Do you have a 2 part driveshaft? The splines might not have any grease...

Ive had several trucks that made a clang or pop when going from reverse to drive. Its just the slop in the driveline catching up with itself. This is not indicative of a problem. The dodge did this, my 1985 F-150 did this....both went on to 200K miles without issue.

I dont know if its normal or not, and it might be fixable, but its certainly not a problem. Hwoever, trying to diagnose over the intertrons is very difficult. Is it still under warranty?

this happened to my dads f150. there was some crap broken loose in the catallytic converter

its a ford, you should expect noises

^

I own a Ford F150 with 212,000 miles and have done nothing more than change the oil, tranny fluid, brakes, tires, filters, lube, etc.

Only major repair was some A/C work, but who doesnt need AC repair in Houston after 150k?

Plus its not slowing down. I will get 300K out of this truck easily. Only noise it makes is through its exhaust..

[This message has been edited by FtBendTxAg (edited 10/7/2008 7:19p).]

No one likes Ford's especially dodge owners. Don't know why, poor quality aggression i guess.

[This message has been edited by jed1154 (edited 10/8/2008 9:44a).]

^ Exactly. Could there be a reason why you hardly see old Dodges chugging along the road like you do Chevys and Fords?

Hmmmmmmmm.......

p-tracs can make noise.....

Ford has issued a bulletin about this. Check out f150forum.com or something along those lines. Just google it.

Good luck changing your spark plugs. I'm about to tackle mine next weekend.

OP needs to check back in and let us know whats up.....

http://www.f150online.com/forums/2004-present/296456-took-2006-f150-rear-end-clunk-today-3.html