Most people ignore their transmission fluid. Old fluid heats up. When it gets hot it comes out the dipstick. The dipstick is near the manifold. BOOM fire.
If you drive on the beach air down to prevent the strain on your transmission.
Do not ignore your transmission get it flushed once a year if you drive regularly on the beach.
ALways always have a fire extinguisher in your beach buggy.
And also look to add a Transmission Fluid Cooler if you don't have one already if you plan on driving on the beach, it will prevent this from happening.
Lots of modern vehicles have "sealed" transmissions that do not have a dipstick. Some will tell you that the fluid never has to be changed, which is not true. It doesn't have to be changed as often. Consult the manual.
Airing down does not prevent strain on the transmission. Driving on the beach puts strain on the transmission, period. Just like towing does.
Most manufacturers advise against flushing. And any good mechanic will if you have high mileage.
Transmission fluid cooler is a good investment if you do a lot of anything besides drive a vehicle on improved roads.
For what little it costs, a fire extinguisher is the best investment you can make. Car, home, boat, RV, tractor...