Changed the front diff case (mobil 1 75w90 2qts.) and transfer case fluid (dexron III 2qts.) about 3 weeks ago for first time at 22,000 miles.

After the change, took the truck out and put it in 4hi drove a bit, no problem. Then put it in neutral and put in 4lo. It felt like it was slipping. It would rev a little, engage move forward and drop out again. It this this a couple of times until the 4lo would engage.

Tried the 4lo again this morning and I get nothing. It justs sits there in neutral and will not engage at all. Tried 4hi and it seemed to work but I'll have to try to do some turns on pavement to see if it really is engaged.

I'll be taking it to the dealer. Was just hoping for some insight as to what the problem might be.

I use 4hi every couple of months or so, only use 4lo occasionally but never had a problem before. I doubt it had anything to do with the fluid change.

Could it be the NSBU?

Was your transfercase making any ticking noises or grinding??

Look at my fun lately. I hope your under warranty
http://dieselplace.com/forum/showthread.php?p=625478#post625478

No, no noise at all. I am definitely under warranty. I'll have to see what the dealer says.

I haven't been fully filled in yet, but from the phone conversations the entire transfercase is being replaced... case and all. I thought that maybe a bearing took a dirt nap, but when they replace the whole thing it must have been some serious carnage.

Keep me updated with what your dealer says.

Well, when I left work I put it in 4hi and did a turn on the pavement just to make sure the 4hi would engage and it did. Then put it in 4lo and it engaged right away without even any slip. Not sure what the problem was but its fine now...

Well, have to keep and eye on it to see if it will do it again...

Mine didn't go into 4-low once when I tried, but I think it was because I wasn't moving enough for the gears to move... It did before that and after...

Mine failed to shift in easily the first few timed when new. I exercise mine every time I have a need for 4X4. This seems to help. Later! Frank

Doesn't 4lo first require you to have in neutral and brake applied before selecting 4lo.(electronic version).


ken

Yes, that's what I did. Pushed 4lo buttone while in neutral while on the brake. When I put it in drive for some reason it just reved without being engaged. It only did it that one time, hasn't done it since.

Mine ('03) doesn't go very smoothly into 4lo unless I first go into 4hi. I'm not sure why, but If I'm in 2hi and I press 4lo, it makes all sorts of nasty clunking noises and doesn't seem to engage nicely.