I Think I Fried My Tranny Or Transfer Case While Driving, Need Help&#3

[camshaft]

Here is some background:

 

For the past say month, I have heard a slight noise coming from what I thought was the dash/firewall area at speeds greater than 60 km/hr. The best description of the noise is like a faint clicking or popping/gurgling sort of noise.

 

The noise was not noticeable below 60km/hr and stayed constant at speeds higher....but didnt get any louder. Truck ran fine until today.

 

I also noted shortly before the truck died tonight, that upon starting it, the 4wd "auto" light came on, as opposed to it defaulting to "2wd". Now that I think about this, it has done that a few times in the past few weeks. I start the truck and it defaulted to "4 auto" and not 2wd. I just popped the switch back to 2wd and it seemed fine.

 

So tonight, I am coming back from a fishing trip, pulling a 2000lb boat. No problems, but hear the above mentioned noise the whole time. I drop off my friends boat, hit the highway, and after about 10 minutes at speed of 100km/hr, the engines rpm suddenly climb, but the truck does not respond. I hit the gas again and the truck does not respond, other than the rpm's rise as if completely in neutral.

 

No noise heard or anything fealt. I try taking out of overdrive and into 3rd gear. Have it for about a minute, then same thing. Drivetrain just disengages and I'm now coasting at 100km/hr tring to find somewhere to pull over.

 

Get the truck pulled over, go thru the gears...nothing, yet again no noise as I do this. Cant smell anything and no fluids leaking under the truck. The engine is still running at this point and once I put it in "park" I hear clunking/grinding noise. I now dont have "park" and the truck is able to move as if in nuetral. I have to put park brake on to prevent truck from rolling as I'm on a slight decline.

 

Pull the tranny dipstick...oil seems fine, up to level, doesnt smell burned and still nice and pink.

 

While waiting for a tow, a guy pulled over and crawled underneath as he thought it may be the transfer case. When I went thru the gears and put the truck back into park, again causing the only grinding sound....he said he could tell it was coming from the transfer case. Made a comment about it seeming like one of the solenoids is stuck or not engaging, and that he didnt think it was the tranny.

 

Oddly enough, the only warrantly or service issue I have had was the dealer replaced the transfer case "encoder sensor" back at 43000km. Back then the 4wd switch wudnt change modes, and it was diagnosed as a faulty sensor. Now I am familiar with how common the switches are, but havent had an issue like this until today.

 

No codes were tripped as of yet.

 

I'm praying my tranny isnt fried.....any thoughts?