HOT WHEELS UNLEASHED

This one is not hard, just a grindy achievement. If you have a friend or a random who needs coins, you can break two birds with one stone and grind a lot of coins together fast! Here's how:


Host a private match and turn on lobby creator. Press "Y" to go to community tracks and head to "Most Likes". Go to the track that says "Money" and select it. When you start, go past the starting line and WAIT FOR 20 SECONDS. If you don't, you won't get any coins. When you and your partner complete the race, 1st place will have 725 coins and 2nd place would have 675. Either way it benefits you and your partner. Do this for an hour and both of y'all will end up with 40,000 coins! Now that's a lot!


Now spend all these coins on blind boxes and grind the cars for gears! Hypothetically, let's say you have 50,000 coins and spent all on boxes, which is 100. Grinding common cars are 50 gears, rare's are 100, legendary's are 200 and super treasure hunts are 500. Let's just say you got 100 common cars and grinded them all, that'll leave you with 5,000 gears!


I know this tactic is monotonous but this is the fastest way to grind for coins! Of course you can play other short tracks like drag and Daytona races. There are plentiful of short tracks if you don't wanna play the same track over and over again.


I hope this helped someone. Have fun!

Update 12/10/2022: It appears seasons are no longer available, and you can't complete old ones, they're just done and gone. Grinding coins to turn into gears and playing through City Rumble are now the only options left currently. I will update again if things change.

---------------------

Since the introduction of Racing Seasons, simply doing the daily challenges every day will net you tons of gears and coins from leveling up. The gear and coin rewards are fortunately free to everyone. The DC Villains season has 13,000 Gears in total in rewards, plus 200 Gears for every level up above tier 50.

Here's the updated way to reaching 25,000 Gears efficiently:

1) 100% the City Rumble mode while making sure to finish daily challenges every day along the way. Completing daily challenges is the only way to get through the tiers at a decent pace.

2) For excess coins, spam buy blind boxes. Upgrade any Common cars you get to Rare to dismantle them for 100 Gears instead of 50, and straight dismantling the rest. The only cars you should be buying out of the shop directly are Super Treasure Hunts, and dismantling them as well. Unless you get duplicates, cars that I recommend keeping and fully upgrading are the 24 Ours, Koenigsegg Jesko, Power Rocket, and K.I.T.T.

3) Grab a buddy or a dummy account on another console and grind out private lobby boosting tracks (custom tracks that consist of only a start line and finish line). 1st place gets 70 coins, 2nd gets 65, and so on. By far the fastest way to boost coins outside of the Racing Season.

4) Grind out short races like Ready, Set, Go! and T-Rex in the Living Room (both can be sub-2 minute races) for consistent coins (50 a race for 1st place).

5) AFK in online quick race lobbies while you're at work/sleeping/out of the house etc. for extra coin income. Rubber-banding your can give you a few higher places every race. This might not even be worth the hassle at this point, as this is becoming more irrelevant with the introduction of Racing Season rewards being 10s of times more rewarding for far less effort.

Also, make sure to check the shop when it refreshes every 1 hour and 30 minutes of in-game time.

Also it’s cumulative total you don’t have to hold 25,000 at one time so upgrade some cars to legendary you don’t need to get 200 gears in return dismantling them.

I have followed and tried many ways to earn coins. The less time consuming is:
Quick modes.
Quick race.
Choose your car.
Choose the race crossroads.
Its the race that has the number 2 and has a pool table on the background of the number.