Help! Dmax won't shift

mschaffer66 · March 11, 2005

I have an 03 Duramax with the Alli, about 60k miles on it. Today i was driving home from work and as i pulled into my sub and got back on the gas to accelerate it downshifted all the way to first and the display on the dash said "Range Shift Inhibited". Then my Engine light, ABS light, and parking brake light came on and the display changed to Service Brake System. So i get home park it.

Then i restarted it and shifted into drive and it was kinda violent, same with reverse. Well i took it for a drive and found 3 things. The service brake message and lights are still on, it won't shift out of first gear, just runs up to the rev limiter, and the speedo doesn't even move.

I called the dealer...they are closed for the weekend. The vehicle is under warranty but i need to go to work monday morning, don't have my 90 in at a new company yet.

If anyone can point me in the right direction PLEASE let me know.

Thank You in advance,

Mike

Mark_in_Tulsa · March 11, 2005

How far away is the nearest GM that is open on Sat?

It might be worth it to have it towed there if you cant take Monday off.

Also a lot of dealer will give you a ride to work if you bring it in first thing in the mornin.

Silverado4x4 · March 11, 2005

Try starting it up and shutting it off 3 times, your prob. in "limp mode" mine did the same but only had the check engine light on. Took it the dealer the next day and they found a wire connecter came off in the trans oil pan.

JimG · March 12, 2005

After MUCH searching on this site (something is wrong with that search engine -searched the words "Range Shift Inhibited" and it could not find the post, but I FINALLY found it: http://www.gm-trucks.com/forums/index.php?...topic=20136&hl=

I knew I had seen that message before ... hope this helps!

Edit - Regarding the work issue: See if you can get a rental from the dealer. My dealer won't give me one unless they need the truck for more than a day (then again, when they crashed my truck I got to drive a rental for a week - be careful what you ask for). May delay you getting to work but it's better to be late than not be there at all.

8100HD · March 12, 2005

Could be the NSBU switch(neutral safety back-up) which is a common problem...one thing to check is fuses..especially the one for the cluster/odometer,this same fuse will have an effect on the tranny...as in not letting it shift...does this to keep the honest people honest.