Hey all

I have a 1995 F150 XLT with a 5.0 and 4R70W.

I recently rebuilt the 4R70W (forward clutch pack was burnt out) and it has been driving perfectly fine.

I noticed a few days ago that there was a noise whenever I revved the engine in park or in neutral.

Drive and Reverse are fine. Transmission fluid level is good. I's coming from under the truck (not from engine bay).

Here is a video of the sound: https://streamable.com/mho7p


Any ideas? As far as I can tell, it doesn't affect driving performance, and only happens if I rev the engine.


---Update---

I used a mechanic stethoscope and seem to have isolated the issue to the bell housing where the flex plate sits. If it were something in that area, why would the noise go away in gear?

 

It turned out to be the torque converter!

When I rebuilt the transmission, I figured the torque converter should be fine and reused it. BIG MISTAKE.

I had to tear the transmission out again, but the new torque converter resolved the issue.

 

My 2019 250 6.2 did the same thing yesterday backing my landscape trailer up a small incline. My truck only has a 1100 miles on it . It felt like it was right under driver seat so I thought it might be a transfer case problem or transmission. It doesn't do it every time ?

 

As you learned, you should never reuse a torque converter especially since there was damage to the clutch pack. ​​​​​​

 

In the mid nineties Ford had a problem with the torque converters shredding vanes. The transmissions were used in rear wheel drive cars and two wheel drive trucks. They never issued a service advisory, but dealt with the problem on a "you bring it in " and we'll check it out basis.

My son had a 95 Mustang that was equipped with one of the bad TC. It was under warranty, only 18 k miles, the dealer had to rebuild it three times to get it right.
One time it did not make it home from the dealer before it went out. It seems the little pieces of metal found their way into every nook and cranny in the transmission case.
The only thing that was original to that transmission was a handful of bolts.

I would ask Ford about the thing you mentioned, soon.