I have a 2005 f-150 4x4 5.4 automatic and a couple of times shifting from 1st to 2nd it shuttered for a second. It has only happened twice l was in stop and go traffic and it was hot out. Just wondering if anyone else has had this problem. Thanks

 

May not be anything major, these trannys will sometimes develop a shudder when the converter clutch applies and it can be nothing more than old fluid that the friction modifiers have broken down in. It may be worth a shot to see if a fluid change would help in your case just don't let it go to long before you try it. Interesting bit of info, the average fluid change only gets about 4-5 quarts of the old fluid out. If you look on the bottom of the bellhousing there is a rubber plug about an inch or so in diameter, pull that plug and rotate the engine over till you can see a threaded plug in the converter, remove that plug and let the conveter drain down and you will get closer to 8-9 quarts of the old fluid out.

 

The torque converters in our trucks do not have a threaded drain plug. If your truck has one (??), then it was added by a previous owner and/or the torque converter was replaced with an aftermarket one with this drain plug. I'd find it hard to insert a socket through a one inch hole of the bellhousing and remove/re-install the torque converter plug as well!

The only way to remove all the fluid for a fresh oil change is to use a flush machine.

Flushing has been debated on this forum to death; some won't do it on a transmission that has high mileage and never had a flush. I've had mine done every 30K without issue. My transmission has 89K and is in perfect operating order.