Originally Posted by MzLiz
When I mentioned to someone that I was gearing down on long steep downgrades (to avoid using my brakes too much) his comment was "brakes are cheaper than a new transmission". ??? I'm interested in what you guys have to think about that. I guess my main concern is always worrying that suddenly the brakes won't be there! When I gear down I immediately feel a little less stressed. (I drive a 1999 F250 diesel and pull a 26.5 5th - 213K miles and still runs like a champ - hope I didn't just jinx myself!).
Allowing the engine and trans to help slow the vehicle down is actually a good idea, as long as you don't allow a steep slope to over-rev the drivetrain. Depending upon the slope, it may be too steep for the drivetrain alone, and you may need to add a little braking once in a while. With a diesel, you can add an exhaust brake if you like, which will help. I never had one in my Chevy Silverado Duramax. My current Seneca does have an exhaust brake, and the previous owner used it religiously. It does save the brakes, which can get very hot on long steep downhills. The best practice in the mountains with a heavy rig is not to get in a hurry. Just take your time and keep an eye on those temp gauges on the up hills.