The GP40 that came in the set has 8 directly geared driven wheels, spaced at the ends of a fairly heavy chassis. While the Praire only has one axle directly driven in what would amount to a single 6 wheel truck in a diesel. Which means the GP40 is going to be able to pull more than the Praire, especially on any kind of grade. Which pretty much matches the prototype. Even in real life, the Praire could never pull anywhere near what a GP40 could haul.

Len

The last entry under 'Bachmann Spectrum Diesels' in the Soundtrax decoder selection shows the various decoders and speaker needed to install sound in your locomotive.  You can get the pricing info by clicking on the link for each of the decoders listed.

https://soundtraxx.com/reference/decoder-selector

Len

You have a straight DC 'A' unit and DCC 'B' unit.  The speed differance is due to the DCC board requiring at least 5 volts on the track before the loco starts moving, while the DC unit will be moving fairly fast at that voltage.

You need to install a AE32033 DCC board in the 'A' unit to make them both DCC capable:

https://estore.bachmanntrains.com/index.php?main_page=product_info&cPath=698&products_id=10488

While they look the same externally, the AE32033 board has light functions the AE32034 in the 'B' unit does not.

Len

These are the parts listed in the Parts Store for the 44 ton loco. Click on an item to see if it is currently in stock.

https://estore.bachmanntrains.com/index.php?main_page=index&cPath=70_814_113

Len

You can make it whatever size you want by adding additional pieces, or removing a straight or two if the basic oval length is too much for your space.

Len

Haven't come across them before. Added to my list of sources.

Len

Aside from the Woodland Scenics 1914 Diamond T grain truck, these guys are probably your best bet for specific era trucks, including grain trucks:

https://sylvanscalemodels.com/Grain%20Trucks.htm

The Woodland Scenics D203 Crates, Barrels, and Sacks kit has most of what you are looking for. Available from a number of on-line sources. Use your search engine to find the best deals.

Len

The upper coupler (16/64") in your pic is a Short Underset Shank Coupler, the lower one (25/64") is a Long Center Shank Coupler.

The short couplers are normally referred to as having a 1/4" shank, rather than 16/64".

A medium, or standard, shank coupler has a length of 19/64".

Len

Seconded!  I've been asking for a real model of a 2-6-2, not that smoking 0-6-0 with pilot and trailing trucks stock on, for years.

Len

You should be able to fit anything using O-99 (8'3" circle) curves, or smaller, inside a 10x10 LS layout.

Len

There should be two track pieces labeled 'A' on one end and 'B' on the other. These are the sections with the gaps that trigger the reversing action.  All the other sections should be labeled 'A' on both ends and have the black channel on the bottom that carries the wires connecting the reversing module to the 'A'-'B' track sections.

The special reversing track 18" radius curves are item 44549.
The special reversing track 9" straights are item 44548.

Regular EZ-Track, without the connecting wires will not work properly with the reversing unit unless you add the additional wires yourself.

Len

Check to be sure you do not have one of the A-B reversing section install backwards. Both of the gaps in the A-B sections should be on the same rail.

Instructions: https://www.bachmanntrains.com/home-usa/dwg/dwgs/HOReversingTrackInstructions.pdf

Len

There is no direction lock switch on Williams, or early Williams by Bachmann, locomotives.  To add a switch you can replace the original reverse board with the newer version that has provision for adding a direction lock switch.

New board: https://estore.bachmanntrains.com/index.php?main_page=product_info&cPath=77_222&products_id=10587

Installation instructions: https://www.bachmanntrains.com/home-usa/dwg/dwgs/WilliamsReverseBoardInst(later).pdf

Len

For the passenger cars, gently squeeze the side of the roof-you can normally "pop" the tabs free of the side and just lift away, one side at a time. If needed, you can use wooden tooth picks inserted between the roof and sides to keep it from dropping back in place while doing the opposite side.

No clue on the caboose, as I do not own one.

Len

If it's used, have you tried a factory reset to clear any previous programing, such as an address change?

Len