Clunk When Switching To 4wd In 2007 Vmax

[VMaxtastic]

Hey guys. This is my first post but ive been creeping this forum for a while. Seems like the best place to ask any questions I have about my truck. I jsut bought a 2007 GMC Vmax extended cab. It now has 80,000km on it. I havent even had to use the 4wd yet, I jsut switched it in my driveway for the heck of it today and noticed a rather loud clunk. Just curious if this sounds familiar to anyone here? Also what on earth is the deal with this message box thing for typing? Is it jsut me, or is it really annoying to use? I see no cursor. and I cant highlight and delete

[nickvrebel]

Try shifting in to 4wd with the transmission in Neutral or while moving ~3 mph, if the problem goes away then the gears just weren't lined up and it's no biggie. In the manual it actually advises that the preferred way to shift into 4HI is with the vehicle moving at a steady rate. I THINK 4LO it states is best to be moving very slowly, pop the transmission to Neutral and select 4LO, but check your manual.

 

 

To fix your posting issues: go to "My Controls" (top left of screen), "Preferences", "Board Settings" then the last item select "Standard Editor"

[cghbuilder86]

On mine 4 lo is supposed to clunk. There would be a problem if it did not. 4 hi is smooth though.

[mxdirtrider56]

On mine 4 lo is supposed to clunk. There would be a problem if it did not. 4 hi is smooth though.

 

 

^^ + 1

[VMaxtastic]

Ok yeah I was definitely not moving when I switched into 4 lo (I did that first). I was in neutral though. You guys are probably right. Ill take a peek at my manual to make sure. Thanks a bunch

[BlackZ71Silverado]

Since yu say you shifted into 4lo first, the clunk you heard was most likely "clunking" out of 4lo and going into 4high.

[VMaxtastic]

Yeah I think nick was right about the gears jsut not lining up. I switched it while rolling and it jsut made a soft thud as it switched into 4wd. Im sure thats just normal.

[Matt_]

Yup... a thud/clunk is normal.

 

If you try to shift into 4wd and you don't hear any noise... that's when id be worried!