Shudder

[Wyomingcowboy]

I have a shudder when decelerating about 25-30 mph. It is with trailer or without and only on deceleration and only at those speeds. U-joints are good and tight.
I have also experienced a weird "clunk" type feeling when starting from a stop with a trailer. It feels like the gooseneck ball is too small for the hitch (it isn't) and I am feeling the extra space move when I start out. After the initial start there are no issues except for the above mentioned shudder.
Are these two related? Any ideas what it could be?

 

[KATOOM]

Usually such clunks and vibration shudders you described are because either the transmission yoke is loose or the differential yoke is loose. While driving along the driveline runs smooth but while taking off and decelerating the yoke reach vibration angles.

 

[JR]

Did you physically disconnect the driveshaft and move each universal joint independently? Thats rrreal the only way to check a universal joint. Carrier bearing condition? axle u bolts tight?

 

[Wyomingcowboy]

I have not disconnected yet. I'll have to find time to try that. Thanks.

Did you physically disconnect the driveshaft and move each universal joint independently? Thats rrreal the only way to check a universal joint. Carrier bearing condition? axle u bolts tight?

 

[JR]

I have not disconnected yet. I'll have to find time to try that. Thanks.

I would definitely try that before digging too much deeper. Assuming you have a 2 piece driveshaft, make an alignment mark on the two shafts prior to disconnecting to assure they are reinstalled correctly.