Cold weather brakes/hydraulics question

[lars]

I own a 2007 New Holland TL100A with 2,000hrs and this past winter when it got real cold (-30f) we lost brakes due to losing some fluid and getting air in the lines. Tractor is usually parked in an unheated barn and when we warmed things up in a heated shed and bled brakes everything worked fine. I'm guessing we have a weak seal in one of the brake pistons that seems to work fine when warm. We plug the tractor in before starting when cold but not sure how long it's warmed up idling as I am not usually operating. I'm sure letting the tractor idle up to temp when its cold would be a good thing, but my question is whether the tractor idling would warm the hydraulic fluid up where the brake piston seals are located and help to keep brake fluid from leaking into axle? We've always made sure to use the correct NH brake fluid.

 

[LouNY]

Most of the NH's I'm familiar with use the mineral oil "brake fluid" which is contained to it's own reservoir and the master cylinders and lines and the brake piston. Warming up the hydraulics wouldn't do much for the brake fluid as there is no contact except at the piston seal in the rear end housing.
Depending on which model of the TL100 you have, we warm up ours by putting a transmission in a gear. Depending on the tractor and the transmission either the range box or the gear box in gear and engaging the main drive. Which ever seems to create the most drag is the one we let spin to warm up the hydraulic fluid.