4x4 shift question.

GMC C1500
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WESTY
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2004 Sierra,auto,4x4 shift on floor hump.
Is it normal for the shift from 2 wd to 4 wd high to make a grinding noise sometime when its cold outside? GM says i can "shift on the fly"at some reasonable speed,but i have been shifting from a dead stop for fear of trashing the tranny. I thought i could shift with the truck moving,thus the "shift on the fly" terminology. Other than that the tranny drive is fine.
Thanks
Nov 3, 2007 at 3:46 PM
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BLACKOP555
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yes you should be able to shift on the fly but i wouldnt attempt it. i usually do it on the stop it is a lot safer i have never shifted a shift on the fly with the truck moving. check for proper fluid level, the automatic hubs might not be locking also for the shift on the fly to work.
Nov 3, 2007 at 7:56 PM
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WESTY
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I posted my thanks earlier,but didn't see it on the site. I'm posting my thanks again.
westy
Nov 9, 2007 at 6:48 PM
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BLACKOP555
  • ✓ASE Certified Mechanic
  • 10,386 POSTS
  • ASE Certified Mechanic
no problem mate, proud to help ya.
Nov 9, 2007 at 7:50 PM
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