I have Grand Vitara model 1999, automatic transmission with the 2.0L engine (SQ420). Now the problem is that when I put it in 4WD mode and drive up a hill the front axles(differential) slip with a loud noise. I have been told that this is due to the problem with the actuator in the front differential and the only solution is to replace the hole unit! Has anyone had this problem?

Oh u mean the front diff is not slipping its popping off anf on then

Uh yes, the front drive is popping off and on. I have been told that this problem is not uncommon on the Grand Vitara , and the differential has to be replaced. But is the new differential any different from the old type?
Does any one know that?

What exactly do you mean by slipping?

If you mean only one tire spins when in 4x4 then that's normal.  We have open front diffs and only 1 tire will get power when under load.

Duh, I know that my English sucks but I am not a moron. I know how 4WD and differential works.
What I am trying to say here is that the actuator that puts the car in 4WD and is located in the front differential is not working like it should be. And all I want to know are any people out there who have experience working with the front differential on the Grand Vitara ?
 

Duh, I know that my English sucks but I am not a moron. I know how 4WD and differential works.
What I am trying to say here is that the actuator that puts the car in 4WD and is located in the front differential is not working like it should be. And all I want to know are any people out there who have experience working with the front differential on the Grand Vitara ?
 

Wow, so polite.  I'm done trying to help.

First of all, no one is saying your a moron.  It's just really annoying to try and help somone with a problem for several days only to find out that you assumed it was one thing, and it was really something else much simpler.  Since you can't look at someone's elses car on the internet it is a good idea to make sure all of the basic things have been checked first.

Now on to your problem.  I have had my 02 for 3 years and never had a problem with the actuator.  I also cannot remember of ever hearing about anyone having a problem with the actuator.  Now, if you wanted to get rid of it you should take a look at this article on Zukiworld.

http://www.zukiworld.com/month_030104/feature_tsb_shiftontheflyremoval.htm

The main prob with the new Grand Vitras is the air pump for the front diff check ur lines and check the pump is working. Wves hen u ingauge the 4WD the pump turns on and moves the diff over a .75 "