I have an 07 Quad Cab w/ automatic trans. and the 4.7 v8.
Last night and this morning the truck started vibrating from the rear. As if the bed was hopping. Also noticed that it required more pedal to maintain speed. I was going about 50mph.

I stopped at an intersection and the turned onto a major hwy where speed limits are higher. I decided to pull over to the shoulder after reaching 60mph for fear that something terrible was wrong. Letting off of the gas to pull to the shoulder was all I had to do. Braking was hardly required. And this hopping or shaking was loud enough to hear once I turned the heater blower off.

I got out and did a once-over around the truck. Looked underneath to make sure everything was fine. Nothing to see. All looked fine.
I didn't turn the truck off while I was stopped.

I got back in and put it in drive and problem was gone.

Driving this morning I experienced the same thing near the end of my trip.

Anyone have any clues.
I seems like something going on in the differential. But then I have also read that there have been various recalls. Not sure if this truck was recalled or not.
I have owned this truck only 7 months.
It has 60,000 miles on it.

Thanks....

 

bring the truck in, sounds like a brake shoe is broken or stuck, another one is the c-clip in the rear end is about to let go, have them change the differential fluid an inspect the clip. if there is an damage it will need to be replaced at a hefty price., unless the truck still has a warrenty

 

Now that I think about it, I have on occassion, noticed a whine or a hum from the drivetrain. Possibly from the rear. I have noticed this from time to time ever since I have owned the truck. It must be the differential.
Something finally let loose, I guess.

 

It could and might be the differential. But my first thought was a hanging brake. A rear shoe is binding up, usually as the result of a misadjusted or bent e-brake linkage. This would explain why it seems like the brake is always on...because it is. This heats up the rear drum and axle flange enough to warp it, hence the vibration. When you stopped the truck, it cooled down enough to return to normal.....then it heated right back up again after you drove a little ways. This was a scenario I experienced in my Ranger. It's really easy to jack up the rear and inspect the rear brakes. If this is the problem, my guess is once you beat the brake drum off, the shoe will fall apart. If you have never replaced drum brakes before, I suggest you take it to a shop, armed with this information. If you want to do it yourself, be prepared to get a complete rebuild kit for the rear drums (drums, shoes, springs, arms) you are going to need it.

 

Thanks for the feedback. I am going to start with the brakes and if all is ok, open the differential. I am an industrial mechanic and I do most of the work on my own vehicles. I've done rear brakes before but this is the first time I have had issues other than normal wear. That's why I was leaning to the differential. I've had rear brakes go over 150,000 miles without issue, since most of the braking is done at the front wheels.

On your thoughts, I did hear some popping from the rear last time I parked it. I got out and stuck my head under there and could hear popping like something cooling off. The muffler was popping too but this was elsewhere.

Thanks for the advice!

 

Great feedback guys! Very helpful info, with best possible reasons! I hope it works out for ya Registered! Once you figure it out, please share it

 

Alright guys...

I have the truck up on stands and both rear wheels off and drums. All appears to be fine. The shoes look great and are wearing evenly. Nothing is out of place. I thought I would never get the drums off! Damn... They had never been removed before. The clips were still in place.

So I guess I'm getting ready to open the differential. Just a note. With the truck up in the air and I spin the wheels with my hand, I can hear the gears meshing in the differential. Its a dull popping sound.

Is that normal? Regardless, I'm going to open it up.

Anything I should know going into this?

The last time I had a differential open was 1985!
I was 15 years old and it was a 1967 Ford F100.

Again, thanks for your help.

 

I've decided to call it a day.

I work nights and have to rest because I have to work tonight at 11pm.

With a general inspection of the rear end I noticed what looked like grass or weeds wrapped around the shaft behind the u-joint.

Thought I would post these pics.

Also... Took a picture of the pumpkin.
Can anyone tell me anything about it.
LSD or not?
Anything... I know nothing. lol

I will tackle this tomorrow.

 

ooof...That can't be good.
Looks like an LSD to me.

 

Do you know where that grass came from? Have you driven it through a field?

There is no way to tell if its a limited slip by looking at the cover. You either have to spin one wheel and look to see how the other wheel reacts, or open it up and look at the carrier itself.

But my advise, not matter what you do to fix that vibration, is to replace that pinion seal ASAP!! Take the driveshaft loose, remove the pinion nut, slide the yoke out, pull the seal out, put the new seal in, grease the seal, slide the yoke back in, tighten the pinion nut to AT LEAST 210 FT*LBS.