Transmission Slipping

[Spclized2]

I need some help. I just performed my truck's first transmission service along with an oil change, fuel filter change, new turbo back exhaust, Bully Dog GT, and Air Lift airbag kit. I drained the fluid, swapped out both filters, refilled the system with Mercron SP and now the transmission is slipping on me when I get onto it. Im getting ready to tow 16,000 lbs from Alaska to Texas and I want to make sure it is good to go. I thought it may have been because I put about 1/2 of a quart of fluid too much into the system making the fluid level over the highest level mark. I siphoned out enough fluid to put the level right in the middle of the "HOT" level when it is running but it is still slipping on me. Any ideas??

[dalton1]

how many miles on the truck? and was it shifting good before?
is it a 6.0?

[CT Performance, Inc.]

Take the BD off and get a SCT with custom tunes..

[Spclized2]

The truck is an 06 with 36K on it. I took the tuner off and brought it to the dealer. They could not duplicate the slipping. The technician hooked up his computer and drove it hard for about 20 miles with no slipping at all, he even went for a ride with me and I couldn't get it to slip anymore. Brought it home and put the tuner back on.... no more slip. Im going to put my 36' trailer on and see if I can get it to slip again.

[kylev90]

x2 on the BD. Get rid of it before its costing you

[Spclized2]

I guess I should have read around this site before I pulled the trigger on my tuner. Too late now, I depart AK for TX in less than a week. Ill have to keep the tuner set to TOW and hope for the best. Everyone keeps raving about the SCT... what specifically makes it better than the others? I bought this one for its multi-gauge setup with on the fly tuning adjustment and ability to hook up a pyrometer. Other than the transmission (which may or may not be tuner related) I have had no issues with it.

[Galaxie]

How did your trip go?