Well... The TC issues went away by themselves. The Service 4WD message still comes on and now the front differential seems to lock up when backing out of the driveway, and turning hard. Once going forward, it acts like an old school 4x4 in 4wd on pavement with the drivetrain winding up. Banging from front differential once or twice (at less than 5 mph) then releasing and it's fine thereafter. Kinda like the clutches are locked in the front axle. The axle's have been serviced w/75-140 synthetic and friction modifier and the trans/transfer case per oem recommendations. Don't know if it's the transfer case, trans, or front diff. Checking for codes. I've never seen the problems like the Commander has on other 4x4's I've owned. (91 Wrangler, 95 Wrangler, 99 Wrangler, 99 Cherokee, 00 Grand Cherokee, F150 and a F250 - most bought new) I put the reman 4.7 in and it has about 1900 miles on it. It runs fine and break in is about complete. I'll be switching to synthetic oil at about 3k miles. I really like the Commander, but from the(computer related) issues they have, I should have passed it up.
Joe
So I'm assuming you have the QDII 4WD system? That is the only one with locking differentials. If you have QTII, the differentials are open and have no clutches and the locking must be something else.
Yea, I'm suspecting something with the 4WD system and its electronic control, the FDCM possibly.
Probably your best option is too get the codes read. The key dance and inexpensive code readers just read OBDII codes, those are fed mandated emission codes, since just about any malfunction with the engine will effect emissions it includes just about all the engines codes.
The rest of the modules and software are NOT federally mandated, and thus don't have to meet the fed rules/laws. So all the manufacturers make these modules and software trouble codes near inaccessible by the owners, to force them back into the Dealerships to pay for diagnostics and repairs.
So, you very likely have trouble codes for the "Service 4WD" light, and the unexpected activation of traction control and differential locking. But, the key dance or inexpensive scanners can't read them. You need to go to the Dealer, a big independent shop that might have the expensive scanners that can read it -OR- buy a very expensive scanner yourself.
I think some of the more reasonable priced "Tuner" devices can read extended codes over just the OBDII, but NOT all of them.
On a related note: The whole N23 fiasco came from defective FDCM that were inadvertently shifting the xfr cases into neutral, and a few Commanders/Grand Cherokees rolled away after parking them. The N23 software update, would disable any shifting of the XFR case if the FDCM failed the self-test. And it had a bad self-test, disabling lots of perfectly good FDCM's.
Perhaps you're FDCM is failing and activating traction control and differential locking.
You can't rule out its all reacting to bogus information from a bad wheel speed sensor, etc.....
Reading the codes will help you narrow down the problem's cause.