Banging at 50mph

[Chris03XLT]

Hello All -

I'm new the forum and also new to Explorers. I recently acquired my late step father's 03 XLT. It has the 4.0, 4x4 and just over 129k miles.
The truck was sitting for about 2 months but prior to that the ball joints, sway bar links and hub bearings were replaced. The transmission is throwing the typical PO745 code, but the 3rd gear slip is very intermittent.
Ok now what's happening is, once the truck gets to 50mph there is a heavy banging and it's consistent with the speed is constant. Below or above 50 it doesn't happen.
I've tried doing a search but haven't found anything.
Any advice would be greatly appreciated.
Thanks!

 

[TechGuru]

You sure it's not a unbalanced tire? Driveshaft spins too fast at that speed to be banging, would be a vibration.

Other thing would be some loose heat shield banging in the wind.

 

[LMHmedchem]

Has the muffler been replaced recently? I have had mufflers bang like that when it was not installed in quite the right spot. When the drive train is under torque, things can move a bit and the hangers can allow enough swing in the muffler that it starts banging on something. Aftermarket mufflers can be pretty generic and may not fit all that perfectly anyway.

Just a thought.

LMHmedchem

 

[Chris03XLT]

I don't think the muffler has been replaced at all.
And all four tires were recently replaced and this sound is definitely not an off balance tire. It's a significant bang. I need to do the brakes within the next few weeks so I'll jiggle things around while I'm "playing".

 

[Chris03XLT]

I guess I should have done a better job with the search function.

My step dad had gotten two front tires put on 2 years ago. Then this past May, he put two on the back. Different brands too. So I pulled fuses 17 and 18 and the noise is gone.

 

[TechGuru]

I guess I should have done a better job with the search function.

My step dad had gotten two front tires put on 2 years ago. Then this past May, he put two on the back. Different brands too. So I pulled fuses 17 and 18 and the noise is gone.

Hmm, this concerns me as normally I can only afford two tires at a time especially if I want nice ones like GoodYear Wrangler.

I would think new on the back would not affect anything because the back would be turning slower than the front so the ECU should not think that the back is slipping...