When letting off the throttle at speed... (1 Viewer)

[maxse01]

guys,

when I'm driving all is well, but when I let off the gas I hear a grumble, kind of sounds like a playing card in bicycle spokes. It just started the other day. It was in recently for oil change and chassis lube, nothing then. Any ideas?

Thanks.

 

[SmoothLC]

What part of the vehicle is it coming from?

 

[maxse01]

Underneath. Maybe the drive shaft?

 

[Trunk Monkey]

A u-joint going out will make a noise on decel, but not like a card in spokes, it's more rumble strip.

 

[maxse01]

Any way to rule out the u-joint or test to see if that's the culprit?

 

[Trunk Monkey]

Remove the DS, lock the center, go for a drive.

 

[maxse01]

Any other way than removing the drive shaft?

 

[maxse01]

Ok, so hypothetically if it is the u joints and I have 5000lbs to tow this weekend...is that going to require repair before or can it wait?

 

[maxse01]

Truck is in the shop right now getting all the u-joints replaced, chassis lube and an oil change while it's there. Just ticked over 99k this morning, so hopefully that solves the sound. Will report back.

 

[maxse01]

Ok, my mechanic tracked the sound to the front drive shaft. He replaced those u-joints but the sound is still there. He changed the transfer case fluid, still there. On the lift he ran it with the diff locked and the sound would go away with all 4 wheels off the ground, but when it's on the road with them locked, it still does it. High range, low range...still there. Any thoughts guys? Transfer case bearings?

 

[PADDO]

Have the spindle bearings been checked and lubed? It's quick and easy to pop the snap rings off and push the shaft in to get eyes on a section off the cv shaft and squirt grease in with a needle adapter.

 

[maxse01]

Not sure, I'll ask him. I was just driving it and heard a loud 'bang' and now I've got a grinding noise at all speeds. Luckily I was around the corner from my house, so I'm going to have it towed back to my mechanic.

 

[maxse01]

Now that it's louder, sound has been tracked to the front diff. Pulling it out and taking it apart to diagnose.

 

[maxse01]

Not to good, pinion has a couple chunks from about 3 teeth. We will be fully dissecting in the AM. And order what we need. I will probably end up doing the carrier bearings also, so basically a full rebuild of the front diff

 

[maxse01]

So the diff is blown up. Go ARB?