Lately my truck has been doing something strange when I put the truck into a tight turn backing up or going forward. It does it once or twice a week. It basically feels like the truck is stuck in four wheel drive. Today as I was pulling forward out of a driveway I turned the truck to the left all the way. It felt like I ran over something and made a loud noise. The truck started to grind like it was in four wheel drive. I stopped the truck and looked under the truck. Nothing! I started to turn again and it did the same thing. I put it in reverse and it stopped. It's really strange. Any ideas?

check front hubs

Lately my truck has been doing something strange when I put the truck into a tight turn backing up or going forward. It does it once or twice a week. It basically feels like the truck is stuck in four wheel drive. Today as I was pulling forward out of a driveway I turned the truck to the left all the way. It felt like I ran over something and made a loud noise. The truck started to grind like it was in four wheel drive. I stopped the truck and looked under the truck. Nothing! I started to turn again and it did the same thing. I put it in reverse and it stopped. It's really strange. Any ideas?

Sounds like a normal G80 Locker. The noise and bang are part of the "normal" operation:rolleyes:. And, yes, a locked in rear axle will feel just like the truck is in four-wheel drive.

X2 on the G80 locker they stay locked sometimes.

X2 on the G80. Mine does it every now and then as well.

mine does the same thing every now and then.

Most likely a stupid question, so be kind.

I bought my truck used, 1 year old at the time.
the original window sheet was not with it, how do I know if I have the locking rear?
is it standard on the dually?
is there some way to tell without climbing under the truck?,, well, actually sending the kid under the truck

open the glove box, look at the code sticker, G80 is the locking rear.

Most likely a stupid question, so be kind.

I bought my truck used, 1 year old at the time.
the original window sheet was not with it, how do I know if I have the locking rear?
is it standard on the dually?
is there some way to tell without climbing under the truck?,, well, actually sending the kid under the truck

Since you didn't get a window sticker when you bought your truck. Doing a Vin check and build sheet will give you alot of useful information on your truck.

chock front of front tires
rasie rears just off ground so they turn freely
put truck in neutral
one person on driver side, one person on pass side
driver person spin wheel forward ( or backwards doesnt matter )
pass side person tries to spin wheel in opposite direction

this may take a few turns to engage

if pass side wheel spins opposite freely = open diff
if pass side wheel is forced around with drivers tire = locker

that wont work with GM g80 you can't spin it fast enough by hand I have tried. If cant find the glove box code pull the cover the G80 will have a bunch of extra parts that a open does not have

or give me the vin ill run it an see what its got.

Since you didn't get a window sticker when you bought your truck. Doing a Vin check and build sheet will give you alot of useful information on your truck.
thanks.
now for stupid question number two. (couple more and y'all be afraid of driving on the same road as me)

how do I do the vin check and build sheet now at this point.

thanks.
now for stupid question number two. (couple more and y'all be afraid of driving on the same road as me)

how do I do the vin check and build sheet now at this point.

or give me the vin ill run it an see what its got.
PM your VIN number to this guy, or have your GM dealer print one out for you.

There is also a VIN Check Requests section on here. http://www.dieselplace.com/forum/forumdisplay.php?f=72