Jump to content

Transmission or tranfer case? Electrical or mechanical?

AaronandAlicia Dailey
 Share

Recommended Posts

AaronandAlicia Dailey New Member

AaronandAlicia Dailey

Posted
Posted

OK everyone I want to give thanks ahead for any advice and help.

 

Truck in question= 2003 Chevy Suburban Z71, 5.3 L         Transmission= 4L60-E

 

So the story started when I was going down the road at about 50mph in cruise control, when suddenly I heard the engine begin to rev up. I hit the brake to take it out of cruise control and the engine stopped revving up. Apparently I lost transmission of power from the engine to the wheels because no matter what gear I put it into now, I get no movement from the vehicle. No reverse and no D1, 2 or 3. When I put the vehicle in park and attempt to push the vehicle it will not roll. When placed in any other gear I can then roll the vehicle freely.

 

Before this happened: Since owning the vehicle 4x4 has always been shifty.....hehehe...sorry couldnt help it. I have the model where there are 4 buttons with lights the buttons are located left hand of dash near the turn signal. When I first got the truck sometimes it seemed like it didnt want to switch between gears. for example I would have to hit the button multiple times before it would switch and even then it seemed like it hadnt really switched but the lights would indicate it had. Most of the time the light for the button I selected would flash multiple times and then return to previous selection. Often times after turning the vehicle off and then returning to vehicle to go somewhere I would find that the light has switched back to a gear that it wasnt in when i left the vehicle. It seems to favor 4x4hi. As of lately I havent been able to get the lights to switch at all. It seems to be stuck in 4hi permanently.  

 

I have tested the 4wd switch and its fine. 

I tried unhooking battery for half hour with lights on to reset PC. I then reconnected battery cable and turned vehicle on but not start it. Then I pulled a bunch of fuses and plugged them back in. ( seen it in a video and the guy said it was supposed to wake up the TCCM) Well that did nothing. 

I have the truck off of all wheels right now and was trying to figure out if the transfer case is stuck in neutral. With the truck in drive as I turn the rear draft the front moves also. I am assuming that means it is in 4wd. But should I have someone hold the front drive shaft while i turn the rear drive shaft to confirm its not just from friction or something.

 

I actually have the front drive shaft partly out right now in an attempt to get at and remove the shift motor and manually put the transfer case into 2hi.

 

I am also considering changing out solenoids. I have gathered it is unlikely the shift solenoids. Is it possible it could be one of these:

1 * EPC (Pressure Control) Solenoid

1 * PWM Solenoid

1 * Manifold Pressure Switch

1 * TCC Solenoid w/Harness

 

Another thing I suspect which would be an easy fix is the transfer case fluid level. I removed the fill plug and nothing came out. I can tell it has been leaking. I would have already topped it off but I have been stuck at home (no running vehicle lol). Could low fluid cause this issue? I hope that's all it is lol. Anyways I got a ride to the store tomorrow and to look at a back-up vehicle. Anything you guys recommend to grab from the parts store while I'm in town tomorrow?

 

What would be your guys recommendation on how to solve this problem and fix it?

 

All help is appreciated.

thanks in advance,

Aaron

 

 

Z45 Senior Enthusiast

Z45

Posted
Posted (edited)

Sounds like the transmission is shot, or possibly th transfer case is stuck in neutral. What color is the fluid?  Anything but cherry red is abnormal.     

 

Its normal for the vehicle to not move in park. The parking pawl locks the transmission output shaft (connected to rear driveshaft) when its in park so the vehicle cannot move with the rear wheels on the ground. Has nothing to do with the operation of the transmission.

Edited by elcamino
AaronandAlicia Dailey New Member

AaronandAlicia Dailey

Posted
  • Author
Posted
2 hours ago, elcamino said:

Sounds like the transmission is shot, or possibly th transfer case is stuck in neutral. What color is the fluid?  Anything but cherry red is abnormal.     

 

Yes it is red

 

 

 

2 hours ago, elcamino said:

Its normal for the vehicle to not move in park. The parking pawl locks the transmission output shaft (connected to rear driveshaft) when its in park so the vehicle cannot move with the rear wheels on the ground. Has nothing to do with the operation of the transmission.

 

Thank you, I understand that it shouldn't roll in park. I only mentioned that to explain that when I  put it into any other gear  it rolls freely. I thought that info may help in the diagnosis.

 

While I have the vehicle off the ground is there any way to confirm whether or not the transfer case is in neutral?

 

 

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing

  • Latest Articles

  • Posts

    • Coastie05
      Replacing 2.7L on 2021 Silverado with 2023 2.7L

      By Coastie05 · Posted

      I’m definitely interested to hear the end result here. 
    • MASONV88888888
      Another 6.2L engine failure!

      By MASONV88888888 · Posted

      My 2025 Silverado 1500 had to receive a brand-new engine (long block) under warranty last month at only around 16,500 miles. Before the replacement, the truck repeatedly displayed "Engine Oil Level Low" warnings, even though the Oil Life Monitor still showed around 50% remaining after about 6,000 miles since my last oil change. After seeing the warning several times, I checked the dipstick with the engine cold, and the oil level was completely normal. The next day, the message escalated to "Add Engine Oil." At first, I assumed it was just a faulty oil level sensor, so I brought the truck to the dealership. After inspecting the engine, they found internal cylinder wall scoring and ultimately replaced the entire long block under warranty. Before this happened, I was planning to install a 4-inch lift and suspension upgrade on my truck. After needing a new engine at just 16,500 miles, I honestly don't see the point anymore. I also contacted GM to ask whether my vehicle qualified for a buyback, but I was informed that it does not at this time. Anyway, this experience has left me with serious concerns about the long-term reliability of this engine. I sincerely hope NHTSA expands the current investigation or recall to include 2025 model and performs a thorough inspection of affected vehicles. My biggest concern is that these engines may fail shortly after the powertrain warranty expires. If GM truly stands behind this engine, then at the very least, please consider extending the powertrain warranty to 10 years for affected owners. That would go a long way toward restoring customer confidence.
    • Grumpy Bear
      OCI, not when but why?

      By Grumpy Bear · Posted

      Without exception but then I'm the odd duck, right? I know what goes into that test, how it is calculated and thus how to beat it. But EPA values are often not beaten by the general public and the government has in past years adjusted the means and methods to come to those values to more closely approximate "Joe Average".    The only real trick to beating that EPA average is don't drive like "Joe Average".    It's the same method you used to profit from "Economic Migration" and in doing so beat the 'stats'. But you, like me, are not "Joe Average".     The thing you don't seem to grasp is this "Purchasing Power Index" isn't forward looking. It doesn't predict what it going to be but looks backward and states what it was. They are not telling us what the THINK, they are telling us what they MEASURED. Example:    Wife says "I'm going to lose 40 pounds by Christmas". May she does, maybe she doesn't but the doctors office who weighed her when she made that statement and again at Christmas only REPORTS what the RESULT was. You and I can banter about what was possible and what aunt Tilly did till the cows come home but the result is the result. Arguing otherwise is.....irrational. That's all I'm saying. This isn't about:      What you are calling a 'Statistic' is a RESULT not a CALCUATION and as a result the RULE. Like gravity as a rule, it can not be broken. 
    • MASONV88888888
      Rattle in the rear!

      By MASONV88888888 · Posted

      Just wanted to say thank you for posting this. Years later, your thread is still helping Silverado owners.   I bought my 2025 Silverado 1500 in January 2025, and I've had what feels like the exact same rattle since day one. After reading your findings, I believe my truck has the same issue with the cable carrier contacting the rear sliding window. To be honest, I had pretty much given up on pursuing the issue. It wasn't until I recently drove another brand's pickup that I realized just how quiet their cabin was—and how noisy mine has been all along. On my truck, the rattle happens on almost any paved road, gets even worse on rougher pavement, and I can even hear it during braking and acceleration.   I actually referenced your thread when submitting my case to GM, hoping they'll recognize this as a recurring issue instead of treating it as an isolated incident. The reason I reached out to GM first is because my dealership told me they would need to keep the truck for at least two days just to diagnose the problem. I was concerned that even after two days, they still might not be able to identify the source of the rattle before giving the truck back to me. I had also asked a few dealerships about this issue during previous service visits, but none of them seemed to know what was causing it or had a solution. That's why I decided to contact GM directly first, hoping they might already have an official repair procedure or guidance for this issue.   I also hope GM eventually comes up with an official fix for this problem. I have a feeling there are many Silverado owners experiencing the same rattle, but most either choose to live with it or simply don't know what the cause is.   Really appreciate you taking the time to document your diagnosis. Your post is still making a difference years later.
    • Buckwild27
      Gas Prices

      By Buckwild27 · Posted

      I have 2 choices. 

  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...