Vehicle questions about wheels and towing



  1. Is it possible to change wheel sizes on a vehicle? IE 24" wheels to 17" wheels?
  2. Is it possible to put 17" wheels on a scooter?
  3. Is towing a vehicle an option? (maybe chains or something?)
  4. Whats the difference between a car battery and a storage battery?

So I found a small town with a pristine SUV sitting inside a garage. This was a lucky find b/c the zombies were too many and I had to run! I managed to start the SUV and drive away, escaping back to my ranch base. Since the escape I’ve been back to the town several times sans the SUV and I’ve been tinkering with all the cars there. None of them work. I found a few that have green engines, but no tires, or bad gas tanks, no controls, etc, etc.

I have a toolbox and jack. I’ve eliminated all the zombies in the area for the moment. I made a travois and started to cannibalize the vehicles for spare parts. I’ve found a Mobile Meth lab and a V12 sports car I would like to “bring home”. Is towing possible?

  1. Yes.
  2. Yes.
  3. No.
  4. Car battery weighs much less and stores much less electric energy. I think it also stores less energy per pound if efficiency matters to you. On the other hand, you need Strength 15 to swap a storage battery unaided, or Strength 1 for a car battery.

Towing isn’t possible at this time. I could give you the whole sob story on it, but basically there are a number of difficulties in the vehicle code that make towing really hard to implement and I’m currently stuck at fixing the first of about 5 or 6 of those major difficulties.

My usual solution is to make a small, folding bike and ride that out to a salvage vehicle, fix the vehicle, fold up the bike, and then drive the vehicle back to base.


Since you are live atm. Do we still have car batteries that weigh 600lbs or whatever huge amount of weight when full? Would be great if that got fixed.


I can understand that. If there is a vehicle in the way, whats the usual practice for moving it? Take it apart and move it piece by piece or ram it and hope it slides out of the way?

I wonder if it would be possible to have a winch. Winches move in straight lines, so if there was a large vehicle that wanted to move a bunch of other vehicles, it would be sort of possible… but I have no idea how difficult that would be to code.

I’ll have to figure that out. I’ll look for a tutorial on creating a folding bike. I found quite a few guides for stuff like a travois and a couple of other vehicles. I got the scooter working (found a scooter with working wheels) so I’m puttering around on that atm, although I have figure out how the battery charges on that.

Thank you for the answers!



Winches sort of solve some of the problems with towing, but have their own complications.

The Towing Problem in CDDA

  1. Vehicles, for the purpose of towing, consist of list of vehicle parts and a position on the map. The ordering of the list of vehicle parts is not 100% consistent turn to turn and there is no guarantee that part X, in the list at position Y on turn Z, will still be in position Y on turn Z+1. This makes it tricky to even know where a tow hitch is located on the map, so even if trailer hitch X was adjacent to tow pin A on turn Z, it’s hard to figure out where hitch X needs to be to stay adjacent to tow pin A on turn Z+1.
  2. Vehicle part positions are handled using a special data structure called tilerays, because CDDA vehicles sheer instead of rotating. That is to say, the horizontal front row of your vehicle when it’s facing north will stay horizontal as you turn northeast, instead of angling. The tileray transformation of position [x,y] at angle Theta to position [x’, y’] at angle Theta+delta is not reversible: you can’t go from [x’, y’] and Theta+delta, subtract delta, and then calculate [x,y]. This caused me no end of trouble when coding bike racks. Anyway, even if I can figure out where hitch X needs to be on turn Z+1, it’s hard to figure out what delta needs to provided to the trailer’s facing to get hitch X to that position because of the tileray problem.
  3. CDDA’s collision code doesn’t understand the idea of trailers, and what is going to happen if I solve problems 1 and 2 is that your trailer is going to sometimes ram into the back of your towing vehicle. This is fixable, but the collision code is a very confusing black box of WTF moments, and before I can fix it I need to understand it and have test cases that demonstrate that any changes I make are making the changes I want to make. I’m currently working on this, but it’s fairly hard.
  4. There’s some minor ordering issues in making sure your towing vehicle moves before your trailer when moving forward, and your trailer moves before your towing vehicle when moving backwards (or that they move together), but those are pretty minor and can be sorted out after the first 3.

Well, What About Winches?

  1. Winches sort of solve problem 1, because you don’t need the winch and the towed vehicle to be adjacent to each other. And they sort of solve problem 2, because it’s also okay if the trailer’s facing doesn’t quite match, because the winch line gives you some space to work with. And they sort of solve problem 3, because you expect winches to run into the back of your vehicle if you’re not careful.
  2. So why haven’t I implemented winches? I’ve been busy and there’s a feature freeze before 0.D. But now that I’ve broken the issues down, winches might be a reasonable solution, especially if I specify that the winch includes wiring to control the trailer’s brakes.


WTF? I’m now your fetch-monkey to look up data that you’re too lazy to look up?

From the JSON:

Item Weight (kg) Capacity Loaded Weight (kg)
Small storage battery 2.5 500 3
Motorbike battery 4 500 4.5
Car battery 18 2,500 20.5
Medium storage battery 31 7,000 38
Storage battery 150 40,000 190

So no, even fully charged car batteries weigh no more than 45 lbs.


i can imagine that storage battery… when used on car and stuff…

would be energizing i see…


Thank you for breaking that down. I appreciate that and man… towing and trailers seems complicated AF!!

Also, apologies… I had no idea there was a change freeze. I just found the game a week or so ago and have been dicking around with it. Most of my questions are born of idle curiosity. Its one thing to sit on the sidelines where I am and point at all sorts of stuff that would be cool or bugs or whatever, but it’s quite another to be in the thick of it making the changes and sorting everything out. Thank you for the effort and for also answering idle questions!



I have a whole procedure worked out for it, 'cause my main game involves driving east forever, and bridges are frequently blocked. Basically I look to see if the vehicle can be made to run first. Jump start, add gas, and move it? Great.
Minor repairs? Do those, then drive it aside.
It’s too busted to drive, but has enough wheels to roll? Hit 10mph and push it with my ram.
It’s got no wheels? Can I swap some from a nearby wreck? If so, do that and use the above.
No spare wheels, badly wrecked, then it’s time for explosives to turn it to a wreck, then 10-15MPH ramming until it collapses.

I imagine the new vehicle split code could be used to hack a vehicle into manageable pieces you could push/pull out of the way.


Currently, the best you can do is put a Cargo Carrier on casters and start disassembling. The biggest issue you’ll likely face is parts that are too heavy for you to lift without a jack or lifting tool. Usually, these involve engines, wheels or storage batteries, the parts you definitely want the most…


I hope the new amphibious vehicles code makes your ability to transition past bridges a little simpler.

You might try setting fires beneath a vehicle. In my vehicle split testing, fires were generally fairly reliable at cutting a vehicle into multiple chunks, especially if you don’t care about the chunks afterwards. And then you can do low-speed rams to shove the chunks out of the way.


Completely unwarranted reaction mate. I figured I had your ear literally a minute after you posted and thought since you wrote the code it maybe a reasonable question. But yes. I must be lazy to ask a yes/no question.


You can put smaller engines, motorbike alternator, and a plastic jerrycan into a folding vehicle with a folding basket. Add a car battery with a small amount of charge in it, and you’ve got a little mo-ped that can get you to from your base to the other side of town. Bonus is that you car battery will charge on the way there.

Get to the vehicle, remove the battery, install it in the beastie you want to take home, and Bob’s your uncle. I sometimes bring a toolbox, welder (with the battery mod that takes the car battery) and even install some jacking/lifting ability onto the folding vehicle, and you’ve really got a portable chop shop.


Really amazing the crap that exists lately. You know that you can buy a folding bike. Put a rear rack on the thing that matches the tire length. Plus you can get a folding box thing that attaches to it and when you wanna take it around the store. You get a telescope handle to use it like a dolly. Blows my mind the cool kit you can get these days. Oh and I forgot to mention they are electric. Crazy!