Volvo Trucks has seen first quarter pre-tax profits jump by 19% as customers stocked up ahead of new EU and US emissions rules for engines.
Volvo sells trucks under a number of brand names
Volvo's pre-tax profit was 5.47bn crowns ($725.2m; £406m) up from 4.60bn crowns a year earlier.
Strong demand boosted earnings, pushing revenues to 60.2bn crowns from 52.25bn.
Stricter truck emission rules come into force in Europe in six months time, and in North America at the end of the year, forcing firms to buy new models.
So now customers have been bringing forward purchases of the older, but cheaper, truck models ahead of the new environmental rules.
"It is the development of earnings in the trucks division that is really strong, due to the mix in Europe and them having pushed through price hikes," said Kaupthing analyst Hampus Engellau.
"In addition, they are raising (market) forecasts."
Volvo is the world's second biggest truck maker, and also manufactures buses.
It sells trucks under the Volvo, Renault and Mack brands, and bought a 13% stake in Japanese truck maker Nissan Diesel in March.
The Volvo car company is now a separate business owned by US auto giant Ford.