You could always call the Parts department. I am sure they can tell you. If it is a gear issue, Shapeways sells printed  replacement gears. shapeways.com

Rich

If you wish to post a photos, you need a photo hosting site to post photo.

Rich

No idea on what you are talking about for top speed. I run my locos at prototypical speeds I found on Internet searches for the loco.

Rich.

The OP could check the Kadee site for recommendations or You Tube site for possible videos.
A search will bring up both sites if the OP really likes the cars from ebay.

Rich

I have just read of two opinions on the Kalmbach, General Discussion Model Railroader forum about this loco you might interested in.

Rich

Here is a short video.

https://youtu.be/5k5ksXeat1g

More videos at You Tube of other F7's. Details in the Information, Parts and DCC pages.

Rich

Maybe these will work.

http://sbs4dcc.com/hoscaleaxlewipers.html

http://www.sbs4dcc.com/znhopowertrucks.html

Rich

Welcome.

I just did a search. How about this or maybe yellow wood glue I use to uses years ago.
Maybe Bachmann has a glue.

https://www.wind-it-up.com/products/laser-cut-kit-glue

Rich

Generally train sets are not but layouts are in many train forums.

Rich

Tough to tell. I was just at the TCS decoder site and looked at the DC version and DCC version and with my eye sight I could not tell. The photo resolution not the best and no idea about fasteners..
Look in the Parts page for shells. Put fence around layout.

Rich

Is that a DC model or a DCC model? I think the  some were Spectrum's at one time. I have seen one type at the TCS site.

Rich

Tough to see the photo. Eyes not so good. My 44 ton came DCC ready with a PC board with markings numbered for DCC wires. I soldered a DZ125 decoder first. NMRA specs. Removed two metal clips first.
Eventually converted to DCC sound.
The DZ125 was quite small. Probably on ebay now. Good for one amp.

Rich

That does sound like an issue with the loco. A re the truck firmly mounted? The motor firmly mounted? Real strange.
I only have the 44ton and 70 ton for diesels.

Rich

A search at Amazon seems to say, no. The box should be labeled DCC if it is. Check the Information page for the loco and see what the loco looks like if it can be DCC. If you are new to DCC, it can be a challenge.

Rich

They also have a delightful selection of N and HO  parts to support  Bachmann trains.

Rich