FS22 AR Frame Beta (Help needed)

Update:
Thanks to Jeremy Brown we were able to partially fix the issue. The wheels no longer lock up when you change gears, but they still do when you let of the gas.
What we did so far:
-Changed the wheels mass
-Changed the truck mass
-Reduced the brakingForce

Uploading the new file with the fixes.

Also looking for someone experienced with gear ratios. I would like to improve mines, so the truck has better and smoother driving behavior. Would very much appreciate if someone can explain to me how those ratios work, so i can improve and adapt the other truck's transmissions too. Write me a message on FB or on Discord.

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I didn't want to do it this way, but if i want to release this mod, i don't have other choice.

I've spent many many hours working on this mod, updating it couple of times and now even completely rebuilding it. It is almost there, but there is 1 issue that i can't find a way to fix and that issue is very annoying and i don't want to release the mod like that so i'm reaching out to you guys for help. For whatever reason, the back wheels on the tandem versions don't spin when you are changing gear and when you are letting off the gas. This issue is really bothering/annoying me, so i have to fix it before i release those mods. For that reason i'm uploading a "Beta" version of the mod with hopes that someone in the community will be able to help me resolve that issue.

I really didn't want to go this way, since i wanted all the new features and options to be a surprise, even talked with a pretty big youtuber to do a review of the mod, before it is released, but i guess you guys will see most of the stuff before that review is even made. Hopefully we can resolve that issue with the wheels, so i can finish the mod and release it to you guys..

I tried solutions like:

-changing the engine parameters

-changing the transmission

-different differential parameters

-different wheel parameters

-different wheel parameters in their xml files

None of those worked so far, maybe i'm missing something, i don't know, hope you guys can help me resolve it.