On my trip a few weeks ago, I got the “Service 4WD” light at about 300 miles into the 600+ mile trip. After a brief rest stop and about 375 miles in the trip, I noticed the 4WD “LOW” light was on and of course the cruise control would not work when 4WD LOW light was on along with the “Check engine” light.

About 450 miles into the trip, took a fuel stop and lunch. Came back out and everything was fine, no lights, cruise control working again. All was OK the rest of the trip going to.

On the way home, again, about 300 miles into the trip, same thing, “Service 4WD”. Again after a brief rest stop, the 4WD LOW light was on and cruise was not working, again. And again, after a longer stop about 400+ miles into the trip, everything was fine, and has been fine since.

I was pulling an 22' enclosed trailer, about 9500 lbs loaded. Juice level #2, tow-haul all the way.

Took truck into dealer, for the above and a few other “small” problems. They could not find anything wrong, no codes, nothing, but fixed all my other complaints, (AC, small oil leak, high beam light indicator, etc).

Anyone else have the “Service 4WD” light come on? If so, what was done to fix or was anything done??

I had a similar issue. The service four wheel drive light was on and I had no lights on the three button electronic selector. The black motor on the transfer case went out and was 700 bucks to fix it. I have an 02 so your setup may be different.

I had a similar problem a few months ago on my 03. There is a TSB out on the issue and a fix.


http://dieselplace.com/forum/forum_posts.asp?TID=277&PN=1

The black motor is shown in that TSB.

I had the same issue with the same result. Dealer says "no code - no fix - no warantee" If we can't find a code to charge the fault to then you pay. $30 dollars please. http://www.dieselplace.com/forum/smileys/Angry.gif http://www.dieselplace.com/forum/smileys/Angry.gif

The black motor is shown in that TSB.





I believe mine is the black one, I thought the black one was to be the fix???


Mine was built in Nov. '02.

Not sure what your question is?

Not sure what your question is?





OK, I could see where my wording was a bit poor on thathttp://www.dieselplace.com/forum/smileys/Big Smile.gif





Seems like I remember about a year ago, and maybe on the other Diesel forum we were talking about this motor being an issue when the Service 4WD light came on.


The "Fix" back then was to replace the "Tan" (I think) motor with the "black" motor. This would "Fix" the problem and was an "Improved Reliability" replacement part.


That make sense??

I do not recall a color of the part was the better part or not. If I remeber the dealer replaced the black motor with another black motor assembly. Are you thinking about the NBSU?

Are you thinking about the NBSU?


http://forums.corvetteforum.com/images/smilies/banghead.gif....you're right, thats what I was thinking about. Damn ol age.