Hi all, this is my first post to any forum. I was curious if our 4wd trucks are supposed to have front axle shafts that dis-engage when in 2wd? Mine always turn even in 2wd. Tanks in advance.

Wreckfisher,


The drive shafts that connect the front diff to the wheels always turn in 2WD or 4WD. The shaft from the transfer case to the front diff only turns in 4WD.

Is there an after market device for manually unlocking the shafts? Maybe this would increase milage/performance? Or am I being petty?

Welcome....


Nothing that I know of as you describe. Personally I think it is better than having to get out and lock hubs when 4x4 is needed. As for performance...I doubt you would see many gains. Just look at Michael Tomac running 12 second 1/4 miles (in 4x4), as well as all the reports of 20+mpg out there.


Hope that helps,


MN.

Today I noticed that the front drive shaft turns freely on my 2003 2500HD D/A CC, while it was parked in 2wd. I was changing the oil and looking for grease fittings and I was able to turn the front drive shaft by hand only to discover that there aren't any zerk fittings in those universals. Oh well.


So the previous post by jbplock is indeed correct!


JimEdited by: 2fast2

Here's what she looks like. That sleeve with the fork on it slides over to the left and covers both splines when in 4x4.

http://www.uscom.com/~hoot/cars/duramax/gmc/headgaskets/images/DSCN4646.jpg

2fast2,


Did you have the front end jacked up, or were the tires on the ground?

They were on the ground.