Since you say "jewel case" (as opposed to "cardboard box") I assume you mean the DCC-Ready version?  https://www.hoseeker.net/bachmannN/bachmannN280consolidationpg2.jpg

-Mark

Those have been put of production for nearly 20 years. Your best bet would be to look for a parts donor on the secondary market (eBay, etc).

-Mark

The decoder in the GP7 is very limited as far as what CVs can be adjusted. The only ones available for modifying speed are CV2 (start voltage), CV3 (acceleration momentum) and CV4 (deceleration momentum).

Full manual can be found here - https://www.bachmanntrains.com/home-usa/images/44913_Decoder_IS.pdf

-Mark

How are you determining that the truck is picking up current but the decoder isn't receiving it? Seems unlikely.

-Mark

It is not available as a separate item - trainset is the only way to get it.

-Mark

I've run these on 9.75" radius curves without any problems. Have you verified that all the wheels are properly gauged?

-Mark

Analog locos can be controlled and operated using a DCC system - just set the locomotive address on your command station to zero. The only downside is that locomotive motors tend to make unpleasant noises when so operated.

-Mark

I don't think I've ever had anything actually repaired by Bachmann. SOP seem to be to just send a replacement (and sometimes not even the same type of loco if they've run out of the original).

I've had Athearn repairs take upwards of 6 months, so the grass isn't necessarily greener on the other side of the fence.

-Mark

The whole board is the decoder, so basically you'd just remove it entirely.

-Mark

It's not a plug-in install, so you'd have to remove the stock decoder board and then solder the wires for track power and motor control to a sound decoder. The headlight LED is actually part of the stock decoder board, so you'd need to wire up your own LED if you want a headlight.



-Mark

The old white plastic (nylon?) gears that were prone to shrinking and cracking were jettisoned back in the early 2000s. They have black plastic gears now.

-Mark

I'm not sure about the Bachmann PCC streetcar, but I've been told that their (newer and better) Peter Witt car can handle curves as sharp as 4.75" radius.



-Mark

Doesn't look good - all of the 4-8-4 driver parts show as "sold out" here. Might have to return the whole thing for a warranty replacement (if that's an option for you).

-Mark

It seems unlikely. Programming track voltages are generally pretty low.

-Mark

Short circuits can be very dangerous for decoders, and switches are the most common place for shorts to occur (like if the wheels pick the wrong rail to follow).

-Mark