U joint still squeaks
 

Just replaced u joints like week, both rear and front on F-150(2008) and it still squeaks. Could squeak be the rear seal?

is the support carrier bearing in good shape ?

Yoke
 

if it's called the yoke yes it was replaced. Doesn't squeak all the time, various times.

Not the yoke - there is a center support bearing for the rear driveshaft. Some trucks have it and some don't. If you have an extended cab you probably have one.

The rear seal was replaced and thought that might be squeak too. Not sure. Hate to replace the real seal again.

First figure out whether you have a hanger bearing (support, carrier) holding up the middle of your driveshaft. If so it could squeak.
If not, did you grease the u-joints well ?
After that I would doubt if it's the driveshaft at all. Something else.

No it' doesn't have that support. Greased good. Who knows. Hate to take it to Ford dealer. They are slow, costly. At least the one here is.
Thanks for input.

Ha just noticed you have a 2008. This is for 87-96 trucks. Completely different suspensions. You might want to post this in the correct forum for 2008 trucks to get better luck.