I have a rattle in my 2002 F250 XL V10. It happens only in drive and going foward. The RPM is at about 2000 and happens between 25 and 45mph. It does it when it is hot and cold. It is worse when it is cold. It is a rattle sound. Just wondering if it happens to anyone elses F250.

 

It likely has the triple plate converter clutch and that is normal operation on them. Might want to look over the exhaust shields. Does it go away when the converter is locked up?
Alan

 

It does not rattle when it is in park or the brake is applied.

 

Thats not converter rattle then. I know ford had some problems with shields inside catayltic converters rattling on the 4.2 models, but I am not aware of the problem on any other vehicles,yet.
Alan