The Orana Rural Fire Service is auctioning off eight of its older trucks with the money raised to go back into the service to buy newer vehicles and equipment.

Orana team district officer infrastructure and assets Mark Pickford reassured members of the community the sale did not leave the service short of vehicles.

"They've already been replaced," he said.

"It is not unusual to sell the trucks but this year we have more on offer than we usually do."

Mr Pickford said most of the 1980s and 1990s-model trucks were category one and seven tankers and there were various reasons why people might be interested in buying them.

"Some people take the tanks off and use them as farm trucks, some register them as their go-to-town trucks, others like the idea of having a fire appliance on their own properties while there are those who need to cart water so they use the truck for that," he said.

Mr Pickford said some of the trucks had not done many kilometres.

"Sometimes because of that people wonder why we sell but most are getting into the 18 to 25-year-old bracket," he said.

"The reason we upgrade is purely for the safety of our firefighters. Just because a truck hasn't done a lot of kilometres doesn't mean it doesn't wear out. The new trucks all have things like upgraded pumps, fire protection halos and heat curtains that firefighters can pull down if they're overrun by fire. Also, we've upgraded some two-wheel-drive trucks to four-wheel-drives."

The sell-off was part of a carefully thought-out, 25-year plan to upgrade the emergency fleet, Mr Pickford explained.

"Yes, it's not a sudden whim where we say, oh, we don't like that one 'cos it's red, we'll pull it out of the fleet," he said.

Mr Pickford said trucks were also being rotated between brigades.

"We have 60 brigades in the Orana region, and while some such as Dubbo headquarters, Mount Arthur, Narromine headquarters, Boothenba, Eulomogo and Minore, for instance, do a lot of fires, there are others that might just do one or two a year," he said.

The auction, which was taking place via online auction site graysonline.com.au had to date attracted bids of between about $2500 to more than $10,000. It would run until Tuesday at 4.30pm. One of the trucks has received more than 100 bids.

"The online auction, we've found, is the easiest and best way to get value back into the service," Mr Pickford said.

"It opens the buying up to a large audience."

The trucks would be sold as is, he said.

"So if you buy one from interstate you have to come and pick it up," Mr Pickford said.

"Some of the trucks you would not be able to take straight onto the fireground because we've removed equipment to use on other vehicles, but you can get a description of each one on the auction site."