# 2000 silverado 2500 transfercase differences



## ontario026 (Dec 22, 2008)

My 2000 Siverado 2500 6L has the auto, 2wd, 4hi, and 4lo settings for the transfer case... What is the deal with the auto setting? mine seems to make more noise in auto than it does in 4hi when driving on relatively dry roads... I have never really ever used auto, and normally only drive in 4hi unless the roads are totally snow covered, but I was just curious as to the difference?

Thanks
Matthew


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## aeronutt (Sep 24, 2008)

The Auto setting is exactly what it sounds like. It automatically engages 4hi when the computer senses the rear wheels slipping. The way it works is it engages the front axle so the front differential and front driveshaft are spinning, but they are only coasting from the vehicle's motion. The transfercase is still in 2hi mode. It's the same effect as the old manual locking hubs being engaged, but the transfer case in 2hi. This does cause some wear on the front axle hardware and will cost you some MPGs from the extra drag, but it allows the transfer case to engage instantly with just a little bump when the computer senses rear wheel spin. The benefit here is that you get 4x4 traction when you need it without the typical 4x4 binding/bucking when turning on good traction surfaces. It's a preference thing, but when I had a 1500 truck with the Auto-Trac transfer case I always ran mine in 2hi unless there was an imminent threat of poor traction conditions when I would use Auto. I only locked in 4hi when I was sure that 2hi wouldn't get the job done. I think 4Lo is self-explanitory...


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## got-h2o (Sep 26, 2008)

Well said aeronutt. I really miss auto since I've been running Dmaxes (the only thing I miss!). It's handy, especially plowing b/c it's not always in 4wd, plus you can turn as tight as you want without cringing. My wife's Tahoe stays in auto most of the winter, she knows to put it in 4hi if it's really bad. Kindof like having AWD.


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