Ok..I have asked every transmission and Dodge Dealership within 75 miles of my house and got NOTHING. Here is my problem and thanks for reading.

While driving on the high way in my 2005 Dodge Ram 4x4 4 door pick up i reach 60mph and let off the gas the truck will Jerk and at 75mph the rear tires lock up and the tires actually "CHIRP" What could be the problem? This has stumped me and I have already replaced the trans control solenoid in the transmission which costs me 800$. The truck as 115000 miles and they are all highway as I commute 85miles daily and only being able to drive 54mph SUCKS Thanks in advance.

 

U joints are good? Diff is in good shape? Never heard of it locking up, and then unlocking... but i had an old toyota the the rear diff went out on, and when it was starting to go out... i'd be driving, let off and it would kind of "shutter"

 

Could be the rearend or the ABS acting stupid.

 

I don't think it would be the ABs, due to the fact he said it's happening when he lets off the gas, not hits the brakes. If he's not hitting the brake pedal, ABS or the brake system is not active.

 

Any way the E-brake could be involved?

 

When was the last time you changed trans fluids or rear gear fluids and inspected the gears?

 

the first place i would look is rear end. dodges are known for there rear ends to lock up when they are going out, happen to my buddy 3 times.

 

I was thinking a possible issue with the differential and the speed sensor in the rearend. On the trucks with stability control, the brakes can engage at anytime.

 

Could be possible the shoe material on the e-brakes have fell off the backer and are getting jammed somehow...That what I found when I took my rear apart to install a locker they fell out onto the floor. Mine never caused any dragging but it may be possible aswell

 

When you let off the gas at 75 MPH, does it sound like the trans downshifts?!? Do the tires stay locked-up till you come to a stop, OR do they simply turn slower than the speed of the vehicle? When the vehicle slows to match the speed of the tires (read ... engine) do they then roll with the speed of the vehicle? What is your rear gear ratio? Sounds like the old muscle car problem with 4.11 gears and a high compression engine. Letting off the gas at 75 MPH with low gear ratio and a high compression engine could cause a sudden rear wheel deceleration, sounding like the rear whels lock-up or chirp at slower speeds and then sound like a lock-up at higher speeds because the wheels have not caught-up with the vehicle.

Just my 2c