help with loss of acceleration

Yup, likely just a fuel filter swap will cure the issue. Likely a 1093 code for "low fuel rail pressure".

A friends 01 dmax was doing the same thing and it needed a new fuel filter.

Fly by wire now days! Ram/Cummins have a condition referred to as dead Pedal. You step on the throttle and nothing happens, and Check engine light comes on. There are some listed trouble shooting steps, but is usually the Throttle Position Sensor.

You might check out some of the DuraMax forums.

My last vehicle went into limp mode.. I took it to an auto parts store and had them put the scanner on it... Told me it was a sensor...

They will check the code it threw... and then tell you which one it was

Agree, went into "limp mode"...to protect itself

Key is to find the root cause and either fix whatever it is, or adjust your
maintenance/service cycle/etc. That will be in the codes set

Even could be that you are over the ratings (or just one rating) that causes the
TV to work too hard

Could even be a loose connection...partially blocked front end
to limit the amounts of cooling air...etc

Yup! You need to read the codes. Most any large auto parts store will do it for you for free. If you have a smart phone app like Torque you can also read them at home. Fuel filter would be my first guess also BTW.

Sounds like the Dmax/Allison went into limp mode.
Have you changed the fuel filter.

Your profile shows a Diesel truck. Maybe it didn't like the gazz your using !!!! :)

It's the age of computers in cars controlling everything. I'd take it to a dealer who can figure it out.
Once on the highway we suddenly could not go more than 35 mph. We limped to a dealer who determined that the engine computer was not communicating properly to the transmission computer so they went into an emergency condition. The dealer shut the engine off for a few minutes, essentially resetting both computers, and the problem went away and we haven't had the problem since in more than a year.