I have one of the early 03's with a 47re. Can I simply swap it out for a later model 48re? Any difference in wiring, etc?

I am considering replacing it (47re) with a rebuilt and would like to get the best towing tranny I can afford.

Lower stall converters of any value while I'm at it? No big mods, just towing an 8000lb 5th wheel.

 

The 47/48 is a direct swap no problems.
A better converter is a must have while the tranny is out.
You might consider an aluminum high capacity pan also, it will help cool the trans, and stiffens up the case a bit too.

 

Probably cheaper to have the 47RE built for towing (suncoast, et. al.)
and would end up stronger than a stock 48RE too.

 

I believe the 03-04s have a TV cable, while the 05(?) and later trucks are all electronic on that front

You can put the majority of the 48s internals into the 47. Not all, but most of them

 

Doesn't matter. The TV motor just drops on top of the same lever theTV cable setups used.

All of the 48RE parts will fit into a 47, as long as the correct dependent pieces are used.

If you can find a 48RE to buy reasonable it will work fine. If not, buy the parts to upgrade it and you will be good to go also.