Auto 4WD 01 Jimmy

I have asked the question before and not received a definitive answer from a gm tech or someone with equivalent qualifications.

I have an 01 Jimmy 55,000 mile on it. When the road is wet from steady rain am I going to do any damage by putting the transfer case in Auto 4WD? If it ok when the road wet from rain what about under dry conditions ? I must also say that I am not worried about reducing gas mileage because it stinks as it is now when I keep it in HI 2. I only get 13-14 in city driving with a VERY light touch on the gas peddle.

Thanks Double tap

Reply to
Double Tap
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I run our 01 Z71 in auto anytime the roads are slick be it rain or ice (don't see much ice in AZ, but it does happen). It is actually good to run it in 4WD as it keeps everything lubed. As far as dry conditions, won't really matter as it won't lock into 4WD unless you get tire slippage on any of the current drive wheels. Open diffs keep damage from occuring. Now if you had the front/rearend locked/spooled then it would be a different story and you could do some damage. So run it in auto all you like.

Reply to
Twistedtrik

"Double Tap" wrote

Why would you need to run in 4x4 when in the rain? Unless you are out in muddy, dirt road style conditions, being in 4x4 won't help you on a rainy asphalt or concrete road.

My personal feeling is that you should not use auto4hi unless you are in low traction conditions like snow, ice. There is no real reason to.

By the way, running in auto4hi does not "keep things lubed" anymore then running in 2hi. Even in 2hi, the auto t/case applies 5-10% torque to the front diff and so the front driveshaft and front diff internals are still turning. The only thing not connected is the right front axle in the extension tube. And it is still being turned by the right axle anyway.

Ian (gm dealer tech for over 25 years now)

Reply to
shiden_kai

Thanks Ian, Since you are a GM tech it is an answer that I have a great deal of confidence in. Double Tap

Reply to
Double Tap

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