I hope someone out there can help with this problem. ! have a 97 F150 reg cab flareside with the 5.4L and E4OD transmission. The problem is a rattle type noise heard in the area of the transmission and torque converter. It makes this noise only when in a drive gear D, 2, 1 or R with the brake applied. As I apply gas and start to roll, the noise goes away. After driving for a bit then stopping again with the brake applied in D the noise comes back. The noise does not appear when in N or P with the brake applied or not. I've heard this could be a torque converter going bad. Any help with this would be appreciated. Dealership not much help.

 

Most likely the heat shield for one or more of the cats is lose, rusted or has sand in it. It doesn't make the sound in park or neutral because the RPMs are higher, creating less vibration.

You may want to bang on the heat shields with something to see if they make any noise.

 

I agree with AjRagno. Had the same problem with a Ranger and it was covered under a recall.

 

I'd tend to agree that it's a loose heat shield. Here's an easy way to test for it. Roll under the truck on a creeper with a rubber mallet. Lightly tap around the exhaust system. You should hear it when you tap the loose part. Ford makes a rather large radiator type clamp to tighten up the heat shield on your converter - if that's it. By the way, torque converters don't "rattle" when they go bad.

 

Thanks guys, you were right on. It is a bad catalytic converter on the drivers side. Now trying to find a replacement at reasonable cost. Dealer wants $850.00. Ouch! Any aftermarket cats out there which are a good replacement?

 

burgflare,

We didn't say that the catalytic coverter was bad, just the heat shield. It's very, very common for them to rust and become loose. The official Ford fix for this is to simply install band clamps around the shield.

You should figure out whether this is the heat shield or the actual cat that is the problem before you spend $800.00+ on a fix. If the cat had actually failed, you'd likely have a check engine light. Also: if it is the cat, they have an 8yr/80,000 mile warranty, if you're still in there.

 

problem found!! Not catalytic converter. Metal Ford placard (plate) found between the cat and its surround heat shield. What a pain. All that worry for nothing. 15 minute fix, thanks for all your help.