On the way home from work last night my truck suddenly shifted bad and slowed me down quick. It made this loud noise similar to a vacuum from the middle rearish of the vehicle. I got out and checked things out but there was nothing visibly wrong and fluids were all there and fine. After I restarted and continued driving the slowing effect was much less but still makes the noise when you increase your speed. It starts at around 5mph and keeps going and getting louder to upwards of 35mph. I haven't tried to see if there is a speed it stops at. It doesn't seem to change tone or volume during turns and isn't imidiate with volume change in regards to speed. So for example if you speed up quick it won't show till 15 mph but will start and pick up pace till it gets to a certain point. The same goes with braking. When you hit the brakes heavily it doesn't slow down any quicker. It only does it when moving. I had to pull my brother out of a snowdrift that morning. Think I destroyed my truck with that?

 

has RPM jumped up? 3.9, 4.7, or 5.9 engine?

 

4.7 engine. The transmission is in rough shape and slips a tad when cold or fully hot. the sound seems to be coming further back than the transmission. Around the rear axle. The RPM isn't really higher. Atleast not that I could tell.

 

From what you saying, It could be the Pinion bearing. You would need to raise the vehicle and verify the sound. And remove the drive line and check the pinion nut, its a 1 1/4 inch socket.

 

Okay. It should be nice and snug right? No movement. I won't be able to work on it till tommorrow so I'll check it out and get back to you on that.

 

So sadly its the pinion bearings. I'm just going to junk the truck. Its got far to much wrong with it to be putting a single dime more into it. Thanks for the help.

 

Those can be replaced.

 

I'm aware. But the engine has 270k miles, transmission is on its last legs, fuel pump is on its last legs, needs new axle bearings, front wheel bearings, rack is on its last legs, and has a heavy amount of rust damage. Right now in good condition the truck sells for 3k in my area. Its just not something I can afford to fix on a 25k a year budget.