Earlier the truck was running fine, after a 30 minute drive I was slowing down at a railroad crossing and felt a strange vibration in the brake pedal. Drove another mile then shut the truck off. 3 hours later I left, and felt that strange vibration in the pedal again.

When I hit the interstate the truck was making a really weird noise, like something up front was loose. By the time I got home it was horrible!

At the light at idle: Horrible noise and vibration throughout the front of the truck.

Gaining speed the noise goes away completely until a shift point then makes a racket which lessens as I accelerate. At highway speed there is little to no noise or vibration.

Gauges read fine, all normal. There weren't any leaks in the driveway when I stopped (still none). I checked the belts they looked ok, fan looks good blades are intact. WTH???

Thanks in advance guys.
Jim

 

Is the noise still there in park or neutral?

 

The way you describe it would seem to be in the front drive area , transfer case / forward , but I would still open hood engine running , grab throttle cable and raise RPM to eliminate engine issues .
Then put the front end up on jack stands , and grab everything that moves or rotates .
Starting with the ft. wheels , grab the top & bottom of the tire , alternately pushing the top & bottom in & out [ looking for lose bearings & ball joints ] , then spinning by hand the wheels , to feel for noise and anything lose , brake parts - like pads , caliper , axial u-joints , then the drive shaft u-joints & the CVC [ thats the large unit near the transfer case , it has 2 u-joints & a centering bearing .
It would be best to have a 2nd person doing the moving , so its easier to see & hear / check all the parts .
Last but not least , check to see if any of the wheel weights have come off .

 

Thanks so much guys....I took off the inspection cover on the bell housing to check if there was any movement of the flex plate, since there have been some bolts that have worked themselves out in the past (other trucks). It was fine. So I took off the intake and dammit if the turbo blades aren't chipped....I couldn't tell if there was any play that was not normal, and the intake was on snugly..What are the secondary damages that can occur when that happens? I can only imagine.
Jim

 

The parts can get caught the intake filter [ intercooler ] , and hopefully not get to intake manifold , then the nest is the parts can bend valves , score up cylinders .
If you get to it early , you need to clean out all intake plumbing , and possibly replace intercooler , very hard to clean out parts , you may be lucky in that only the exhaust side is throwing parts , but look through the intake going to intercooler , to see signs of parts .

 

Jim,
I'd bite the bullet and get a new intercooler... that would be much cheaper than having to rebuild the engine...
Let me know what you decide to do and when you get a new turbo in.. we can get it in there in a couple of hours....

 

Mine ground off half the blade material on the exhaust side. Sorry yours is on the intake side. I never got a vibration in the brake pedal but the noise was terrible.