This game is known in Chinese as tuo la ji (拖拉机) (meaning 'tractor') or bashi fen (八十分) (meaning '80 points'). It is an expanded version of sishi fen ('40 points') using two or more decks, and is related to zhao pengyou ('looking for friends'). All these games are collectively known as Sheng1 Ji2 (升级), which means "raise level" or "promote". Tractor is widely popular in China, especially in Shanghai and south of the Yellow River where it has practically displaced the older single deck game.
There are four players in two fixed partnerships, partners sitting opposite each other. A double deck of standard international cards is used, with four jokers - two red and two black. There are 108 cards in the deck altogether. (For versions with more than four players and more than two decks see variations.
The object of the game is to win tricks containing kings, tens and fives. Kings and tens are worth 10 points each, fives are worth 5 points each, and all other cards are worthless. There are 200 points in the pack in total.
Usually, the jokers, all cards of a particular suit and all cards of a particular rank are trumps. The highest trumps are the red jokers, then the black jokers, then the cards that belong to both the trump suit and the trump rank, then the other cards of the trump rank (all equal), then the remaining cards of the trump suit in descending order from ace to two. In the other suits, the cards rank from ace (high) down to two (low) omitting the trump rank.
For example, if sevens and clubs are trumps, the trumps from high to low are: red joker, black joker, 
7, other sevens (equal in rank), A, K, Q, J, 10, 9, 8, 6, 5, 4, 3, 2.
The cards in each of the other suits rank: A, K, Q, J, 10, 9, 8, 6, 5, 4, 3, 2.
Note that for the purposes of the play, the cards of the trump rank count as belonging to the trump suit, not to the suits marked on them. The jokers also belong to the trump suit.
In some deals there is no trump suit. In that case the only trumps are the four jokers, red jokers beating black jokers. The cards of all four non-trump suits rank from high to low: A, K, Q, J, 10, 9, 8, 7, 6, 5, 4, 3, 2.
The scores of the teams are expressed as card ranks. At the start of the game, each partnership has the lowest possible score, which is two. By winning games, a partnership can increase its score to a higher rank: three, four, five and so on. Above ten come jack, queen, king and ace. The objective is to achieve a score higher than ace - the partnership that achieves this wins the game.
In each hand, one team are the declarers, sometimes known in Chinese as dang1 zhuang1 (当庄), and the other team are the opponents. (In a previous version of this page the teams were called "attackers" and "defenders", but it has become clear that some players use these words in the exact opposite sense to the one used here. Hopefully "declarers" and "opponents" will avoid ambiguity.) In the first hand, either team can by declarers, depending on who makes trumps. In subsequent hands, the team that won the previous hand are the declarers, and the other team are the opponents.
One member of the declarers' team is the starter, who has the advantage of taking the last cards in the deal, discarding some cards, and leading to the first trick. While the declarers try to increase their score, the opponents' objective is to take at least 80 card points, in which case they become the declarers for the next deal.
Deal and play are anticlockwise. The cards are shuffled and stacked face down in the centre of the table. Each player in turn takes a card from the top of the pack, continuing around the table in anticlockwise until each player has 25 cards, leaving 8 cards face down on the table. The players look at the cards they take, adding them to their hands, but not showing them to the other players.
In the first hand the trump rank is two. In subsequent hands, the trump rank is equal to the score of the declarers' team (the team that won the previous hand). Trumps are made during the deal, by a player exposing face up on the table a card of the trump rank, or two identical cards of the trump rank, or two identical jokers. The trump suit is the suit of the exposed card. If identical jokers are exposed, there are no trumps (and the trump rank has no special status in that deal).
If you draw a card of the trump rank during the deal, you are not obliged to expose it immediately or at all. You may wait to see more of your hand, so that you can better decide whether you wish to make to make this suit trumps. You may hope that you will later pick up other cards of the trump rank, giving you a choice of suit. However, if another player exposes a trump before you do so, you can no longer make trumps by exposing a single card. After a trump rank card has been exposed, the trump suit can only be changed if another player exposes two identical trump rank cards. The suit of these cards then supersedes the first exposed suit. If a pair of identical trump rank cards has been exposed, the trump suit cannot be changed, but it can be eliminated by another player exposing a pair of identical jokers, so that there will be no trumps except jokers in that hand.
You can also make trumps by exposing a pair of identical trump rank cards even if no one has previously exposed a single card, and you can make no trumps by exposing jokers even if no one has tried to make a trump suit or if only a single card has been exposed. If you have already made trumps by exposing a single card, you cannot later change the trump suit yourself by exposing a pair, but you can use a pair to change a trump suit made by your partner with a single card if you wish to. If another player overrules your single exposed trump with a pair, you may in turn overrule their trumps by exposing a pair of jokers for no trumps.
In each deal, one member of the declarers' team is the starter. This player takes the last eight cards, adds them to his or her hand without showing them to the other players, and discards eight cards face down. It can be risky to discard valuable cards, because the point value (if any) of these discarded cards will be doubled (or possibly multiplied by a higher factor) and given to the team that wins the last trick - see scoring. The starter also leads to the first trick.
In the first deal, the player who shuffles and takes the first card from the pack is chosen at random. The player who finally makes trumps becomes the starter, and the starter's team are the declarers.
In subsequent deals, if the declarers won the previous deal, the new starter is the previous starter's partner. If the opponents won, becoming the new declarers, the starter is the player to the previous starter's right.
It sometimes happens that when everyone has taken their 25 cards, no one has yet exposed a card or cards to make trumps. This will happen when the players who have trump rank cards have few other accompanying cards in the same suit, and so do not want the suit as trumps. There is then a pause, to see whether anyone wishes at this stage to expose a trump. If no one wants to, the last eight cards are turned face up one at a time. If a card of the trump rank is found, its suit becomes trumps and no further cards are exposed. If all eight cards are exposed and contain no trump rank card, the trump suit is determined by the highest of these cards (not counting any jokers that may be there). If there are two or more equal highest cards, the first of these that was exposed determines the trump suit. The starter then takes the eight cards as usual and discards eight.
The above procedure applies in the second and subsequent hands, where the starter is known before the deal. It is extremely unlikely that in the first hand no one would expose a trump from their 25 cards, because by making trumps your team gains the advantage of being the declarers. If this did happen, the cards would be thrown in and the deal repeated.
After discarding eight cards, the starter leads to the first trick. There are four kinds of lead, each of which will be discussed in turn below:
Each of the other players in anticlockwise order around the table must play the same number of cards as were led, following suit as far as possible. Note that the jokers and the trump rank cards count as belonging to the trump suit. The winner of the trick is determined according to the rules set out below for each type of lead. The winner of each trick leads to the next trick, and may again lead a single card, pair, sequence of pairs or top set.
If an opponent of the starter wins the trick, any valuable cards (kings, tens and fives) that it contains are placed face up in front of one of the opponents. The remaining cards are placed face down in a waste pile in front of the starter's partner - keeping them well separated from the starter's discards, which are stored face down in front of the starter. If the declarers' team wins the trick, all the cards in it are placed face down on the waste pile in front of the starter's partner. In this way it is always possible to see by looking at the face up cards in front of the opponents how many points they have so far collected. The total number of card points collected by the opponents determines the result: the opponents win if they have 80 points or more.
5 is led. This is a trump, so each of the other players must play a diamond, a five or a joker if possible. If the cards played to the trick are 5, 
Q, 10 and 
5 in that order, the player of the 5 wins the trick, since this was played before the equally high 5.7 is led. This is not a trump, so the other players must play hearts (other than the five) if they can. If your only heart is the five, you may play it on this trick, but you are not obliged to; you are unable to follow suit with a non-trump heart, so you may play any card. If the cards played to the trick are 7, J, J, 10, the ten wins, since it is the highest heart that was played.9-9, but 9-9 would not be a legal lead.
9-9 and 9-9 when nines and spades are trumps - then the first played of these pairs would beat the other. It is not possible to win the trick with two unpaired trumps.
J-J; West has no club pair and plays A-Q; South has only one club and plays 4-10; East, whose clubs are 10, 10, 7, 6, 3, would like to play two worthless low clubs, but must follow with the pair 10-10. North wins the trick, since West's unpaired clubs cannot beat a pair.5-5, West beats this with K-K, South, having no clubs, trumps with 2-2 and East, who has nothing but trumps, plays 8-7. South wins the trick since East's trumps, though higher, are not a pair.8-8-9-9. Two consectutive pairs are known as a tractor, after which the game is named.J-J-Q-Q-K-K. Three or more consecutive pairs are named after various other vehicles. Unfortunately I do not know what names are used, except that five consecutive pairs are a tank.3-3-5-5. When fours are trumps, threes and fives become consecutive.A-A-4-4. This is a valid tractor because four in a suit other than diamonds is the next rank above ace.4-4-4-4. These ranks are also adjacent when fours and diamonds are trumps.4-4-[black joker]-[black joker]5-5-7-7. Ranks not adjacent (six missing).8-8-9-9. Different suits.4-4-5-5. Not adjacent: fours are trumps; fives are not.3-3-4-4. Not adjacent: fours are high trumps; next rank above three is five.4-4-4-4. Ranks are equal, not adjacent.3-3-4-4. South's hearts are J, 10, 10, 8, 6, 5, 5 and South is forced to follow with pairs: 10-10-5-5. East and North do not have heart pairs and follow with unmatched cards. West wins the trick because South's pairs, though they are higher, are not consecutive.A-K-K is a valid lead, since there is only one other heart ace at large so the K-K is unbeatable in hearts.A-K-Q-Q-10 is a valid lead (there is no outstanding spade to beat the 10).A-Q is a valid lead.A-Q-Q-J is not a valid lead because the jack could be beaten by the outstanding king.A-Q-Q, West trumps with A-5-5, South overtrumps with 2-7-7 and East plays three clubs. South wins with the higher trump pair.A-K-Q, West trumps with 2-7-7, South overtrumps with A-5-5 and East plays three clubs. South wins again because the A beats the 7 - pairs are now irrelevant since no pair was led.A-K, West trumps with A-3, South has no clubs and A and Q but these two trumps will not beat West's, because only the highest trump is compared, and West's A was played first.The result depends on the number of card points won by the opponents.
If the opponents won the last trick, the eight cards discarded by the starter are exposed. If the starter's discard contains any kings, tens or fives, the opponents score twice the value of these cards if the last trick was a single card trick. If the last trick was a multiple trick, then the value of the discards is multiplied by twice the number of cards led to the last trick. For example if the last trick is a tractor trick (four cards) and the opponents win it, they will score eight times the value of any cards in the starter's discard. Any points that the opponents score for the starter's discard are added to the points that they won in tricks during the play, as represented by the cards that are face up in front of them.
If the declarers won the last trick, the opponents just win the point value of the cards that they won in tricks, which are kept face up on the table.
The possible results are given in the following table.
| Opponents' card points | Result | Next starter |
|---|---|---|
| 0 | Declarers' score increased by three ranks | Starter's partner |
| 5 - 35 | Declarers' score increased by two ranks | Starter's partner |
| 40 - 75 | Declarers' score increased by one rank | Starter's partner |
| 80 - 115 | Opponents become declarers; no change in score | Player to starter's right |
| 120 - 155 | Opponents become declarers and go up one rank | Player to starter's right |
| 160 - 195 | Opponents become declarers and go up two ranks | Player to starter's right |
| 200 - 235 * | Opponents become declarers and go up three ranks | Player to starter's right |
| * Although there are only 200 points in the pack, it is possible for the opponents to have more than 200 points by scoring for points in the talon. It is even conceivable, though unlikely, that they might have 240 or more points, in which case they go up a further rank for each increment of 40 points. | ||
Example. North and South are the declarers with a score of 7 and East and West, the opponents have 10. South is the starter. If E-W take 60 points, N-S increase their score to 8 and North is the new starter. If E-W take 85 points, the scores stay at 7 for N-S and 10 for E-W but E-W become the declarers with East as starter. If E-W take 160 points, again E-W become the declarers with East as starter, but E-W's score is also increased by two ranks to 'queen', so that queens will be the trump rank in the next hand.
As already mentioned, the winners of the whole game are the first team whose score goes above the rank of ace.
6's left then 5-5-7-7 becomes a tractor, and even 5-5-9-9-J-J becomes valid if there are no 6's, 7's, 8's or 10's of spades remaining in play.