Dodge Down, Need Help!!!!

[JohnHaggerty]

Folks,

Transmission or transfer case now at a point where I don't trust going anywhere. I'm not sure what the problem is. Only 38K on the truck with no heavy or hard towing.



About a year ago I couldn't get it to move and heard noises from either the transfer case or transmission. I forget how I got it to move, but I did. Drove a few miles then parked it. Re-started and again no movement and noises while in drive. I switched the transfer case and was able to get it to move.



I've had similar problems over the last year but was aways able to use the transfer case and get it to move and switch it back into 2wd. During all of this I hear scary noises coming from either the transfer case or transmission.



Friday I put it in drive and no movement. Able to get it to move by putting it in 4wd. After movement and putting it back in 2wd lots of noise what seemed like slipping. I had no confidence taking it anywhere.



Any ideas?



Someone please explain the sequence of the drive line to me. e. g, Shift selector to ? to? to? thru ? etc...



At 38K and 5+ years, any warranty on this???



Thanks in advance,

John

 

[sag2]

Have you ever hit the key fob to unlock the doors and heard noises coming from the transfer case? If there is a short or high resistance in the 5v electric shift circuit it can make a shift by itself.
I'm not sure I understand your question completely but here goes. (This is somewhat general as there were some differences between years).
The transmission shifting is completely separate from the transfer case. The output shaft of the transmission enters the transfer case and from there is directed to the rear wheels, front and rear wheels, front and rear wheels in low range, and neutral. The electric shift system uses pretty good logic to keep the truck in the proper gear, or in the case of a failure in any gear. The shift light is used as a simple indicator of a proper shift, or trouble. If a shift is commanded the shifter light will continue to blink until the shift is completed. If the shift motor is not commanded to the neutral position, it will attempt to make the requested shift. If for any reason it is not able to make the commanded shift, it will attempt to make a shift into ANY position except neutral to keep the vehicle from rolling away when placed in park.
The biggest concern areas are the connectors (water, corrosion) and the shift motor assembly. The shift motor has position switches inside to tell the controller what gear position it is in. If they are bad the shifter system is not able to confirm where it is.
Unfortunately you did not provide quite enough information to help out with diagnosing it. Most important is what the shifter light was doing. Then what type of noise was it making? When you put the transmission in gear was it a gear grinding sound? If the truck was in park and shut off did the truck roll (shift motor, not shift switch in neutral position) or does it hit the park gear and stop? If you shut off the engine and move the shifter selection switch to 2wd or 4wd does it make the shift? Although the owners manual says all shifts can be made with the engine running and the vehicle moving, they are generally easier for the shift motor to complete when the engine is off, transmission in neutral, and your foot off the brake if not on an incline, or rolling slowly if on incline. What is the shifter light doing then? Have you taken it in for the dealer to scan for any stored codes after the problem occurs?

 

[JohnHaggerty]

Sag2,
I think maybe I sent you thinking in the wrong direction. I think the only reason transfer case is in this discussion is because i mentioned that I use the 4wd to make the truck move when it can't move like normal.

The truck sat for a few days this weekend and the 4wd selector was still in 4wd (the only way I could move it without acting up). Today I started it while still in 4wd. After start moved switch into 2wd and truck reversed fine. Selected to drive and all well. Drove a couple of miles and parked it while running. Sat running for two minutes. Put it back into drive and no movement right away. Gave it a little fuel pedal and a minor bang and then moving.

The best description of the symptons I can give (without describing the noises) is when I put the gear selector into drive the truck dosn't move. I can sometimes give it pedal and it will bang into gear or I can use the 4wd selector and it bangs into gear.

The noise is tougher to describe, I'm thinking it's electrical causing mechanical noises.

Thanks,
John

 

[cerberusiam]

This could be a transmisison issue also. The transmission is shifted by solenoids and controlled by pressure. If you can always get it to engage by revving the engine a bit I would start with the transmission. T-case is a possibility but not as likely as trans issue.

 

[sag2]

I would tend to agree that you have a transmission problem. Sounds like you need a scan tool. The pressure taps are only available with a special transmission pan the dealers have.

 

[transe]

Hmmm... .



Is it possible you have some broken teeth on the ring gear in your rear axle? That would explain 4WD working when 2WD doesn't. Maybe, if you happen to stop where the broken are lined up (in 2WD) it acts like Neutral, then maybe catches (with a bang) if the truck rolls a little bit.



To diagnose, it would be best if you could read fault codes, or check the trans output speed (to see whether trans is feeding power into the T/case). But if you can't do that:



When you get it to work, does the trans shift OK through all gears? If so, I would not necessarily suspect a trans problem, since it should set a fault code (when it's screwing up) and then be in limp-in once you get it going. So how about this: Next time you get no movement, have someone get out and look under the truck, to see if the rear propshaft is rotating. If so, that says axle gear failure. If not, post again and we'll take it from there.



By the way, I agree that if your transfer case is inadvertently shifting itself (into Neutral) that could give you similar problems. Actually, that would be my first bet, but since you say shifting to 2WD often does not help, I am figuring the T/case is not in Neutral.

 

[fox]

Does park hold it? If so the transfer case is engaged!

 

[jhenderson]

I fail to see how engaging 4wd to get the truck to move indicates transmission trouble.