Toyota TUNDRA Manual page 185

Bumper towing (vehicles with steel bumper only)
The rear bumper of your vehicle is
equipped with a hole to install a
trailer ball. If you have any ques-
tions, contact your Toyota dealer.
The gross trailer weight (trailer
weight plus cargo weight) when
towing with the bumper must never
exceed the TWR (→P. 177) or
5000 lb. (2268 kg) whichever is
lower.
Selecting trailer ball
Use the correct trailer ball for your application.
1
Trailer ball load rating
Matches or exceeds the gross
trailer weight rating of the trailer.
2
Ball diameter
Matches the size of the trailer cou-
pler. Most couplers are stamped
with the required trailer ball size.
Trailer class
Typical trailer ball size
3
Shank length
Protrudes beyond the bottom of the lock washer and nut by at least 2
threads.
4
Shank diameter
Matches the ball mount hole diameter size.
IV
2 5/16 in.
4-1. Before driving
II and III
2 in. 1 7/8 in.
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