Transmission problem: faults out in 3rd-4th gear, stuck in LHM

wdavi014

'05 2500 140 High Top
Hello all,

I'm having issues with my transmission and looking for help. Driving 2005 2500 SHC, 140 WB, 204,000 miles. Here is the order of events:

Noticed crack in radiator expansion tank after low coolant light. On the way to the shop a week later to have the radiator replaced, the transmission wouldn't shift past 3rd or 4th gear (was stuck around 40 MPH), then went into limp mode.​

Cycled the key and it reset, then tried driving in manual mode. This worked until 4th gear, then it got stuck. Cycling the key reset it again, but couldn't use manual mode. It was stuck in "D" and maxing out in 3rd or 4th gear. I think cycling the key at this point no longer reset it. Then CEL came on.​

The shop did the following diagnostics after replacing the radiator:

Checked engine faults; P3323 in EGS control unit, gear comparison was negative several times.​
Checked for faults in TCM, couldn't communicate with module.​
R&R module checked for fluid intrusion, none present at the time.​
Tested power and ground to module C1 Pin27 = 12.2V KDEO, C1 Pin30 1.8 ohms to ground - OK.​
Corrected ATF fluid level and road tested; verified in limp mode.​
After road test, tried scan tool again and could communicate with TCM normally.​
Checked TCM faults; P2503 gear comparison was negative several times.​
Checked TCM values and found control unit is recognizing P/R/N all normally, then faults out when vehicle is shifted into D.​
The shop replaced the conductor plate and the transmission adapter plug, which was loose. Then did the following:

Cleared faults and performed test drive. Vehicle still acting up after repairs.​
No longer sets a fault right when the transmission is put into drive, but it did set a fault when shifting from 3rd - 4th gear.​
It then went into limp model until the key was cycled and resets the computer.​
They then suspected either a piston or valve in the valve body is not functioning properly (hydraulic issue).​
They also suspected worn clutch packs (mechanical issue), possibly k3.​
At this point, they referred me to a transmission specialist, who performed their own diagnostic. Here are his notes:
In limp mode. Will upshift out of 2nd gear. Scanned control modules and found 2232-001 in engine module. Found P2503 in EGS module Gear comparison was negative several times.​
Fluid level and condition are both good; serviced recently.​
Monitored transmission sensors via scan tool while road testing. Intermittently the EGS module loses communication. Before it loses communication, the readings for the input shaft and output shaft speed sensors go to zero. The upshift doesn't seem to be commanded. There may be an issue in the EGS module.​
The transmission specialist suspected that I needed a new transmission control module and referred me to the only place in town who could do the programming -- the Chrysler dealership. They quoted $1500 for the TCM + 500 labor. No thank you.

I called the good Doktor A and he recommended that I mail him my TCM and he would test it in a working Sprinter. Then, he'd either reprogram mine or send me a used working one. At the very least, it would rule out the TCM. He's looking at it now, but based on the notes I provided, he's now thinking it's probably a transmission issue, not TCM.

Any insight or advice is greatly appreciated!!! I'm a full-timer (also work full-time out of this thing) and currently parked w/o a TCM in the Deschutes NF about 8 miles from Bend, OR.

Warren
 

wdavi014

'05 2500 140 High Top
So, Doktor A tested the TCM in a working Sprinter and it didn't cause any issues. The only thing he noted was that it produced an alarming degree of RSN when the test vehicle previously had none. He reset the adaptations and mailed it back, then I plugged it in and went for a test drive. I'm still having the same problem :bash:. It won't shift from 3rd to 4th, and when it tries, it faults out and produces the following codes (at approximately 32 mph):

P0730 (using DRBII scan tool)
P2232 in ECM (using DRBIII scan tool)
P2504 in TCM (using DRBIII scan tool)

I had a few opportunities to test shifting through the gears before it went into permanent limp mode, and in all but one case, it wouldn't shift into 4th gear (~I maxed out at ~45 mph at 2900 rpm).

Usually, when trying to shift into 4th, there felt like a brief acceleration, almost a hesitation when trying to shift, and this repeated itself as I tried to go faster than ~50 mph. It wouldn't go into 4th, however. Is this what clutch slippage feels like? I've felt it with manual transmissions, and it isn't the same as I could eventually get into the desired gear.

On one occasion, I was able to use the Tiptronic mode and get it into 4th but with a weird sequence. I set Tiptronic mode to 3rd and brought speed to ~55 mph, then used shifter to change quickly to D to see if it would skip 4th and go into 5th. Nothing happened, was still in 3rd for 15 or 20 seconds. Then manually set to 4; nothing for 10 or 15 seconds. Then back down to 3rd and it immediately upshifted to 4th gear. The indicator said 3 and was stuck at that point; couldn't change using the shifter. When I came to a stop, I was still in 4th gear. As you can imagine, I couldn't really move from a stop so I cycled the key and all was normal again.

If I use Tiptronic mode and leave it in 3rd, the fault doesn't produce after driving around for ~15 miles. It only seems to produce when trying for 4th gear.

If I initially put the shift lever in 4 and drive, it faults when trying for 4th and gets stuck in 4. At that point, I can't manually change the gear.
If I initially put the shift lever in D and drive, it faults when trying for 4th and gets stuck in D. At that point, I can't manually change the gear.

Other observations:

Some sources indicate the source of these codes could be electrical in nature. Perhaps an important note -- the van spent the first 185,000 miles around coastal Virginia, near salty air and occasionally salted roads during the winter. I read that this could cause corrosion, and thus a rough surface near the fuel filter harness attachment points, damage the wire insulation, and produce these codes. :idunno:Haven't been able to check this yet but I will tonight. Are there other places I should look? Specific relays or other wires?

The wires under the driver seat near the TCM are super dirty, but no signs of damage (by rodent or otherwise) and it's dry (no tranny fluid wicking up from a leaking TCM connector).

Over the last few months, I noticed that the shift lever would sometimes not go into Tiptronic mode, it would stay in D. Everything else was totally normal. Cycling the key would fix the issue. Is this an indicator of a faulty shift lever assembly, and could that be the cause of the issue I'm having?

I took it to a transmission shop this morning and they found the following codes when checking other modules. I don't think these are related but who knows? Not me.

P1926/ code not valid for ECM
P1925/ C.A.N fault brake

When trying to clear all the codes, they tried two scan tools and both kept losing communication. Eventually, they said they couldn't communicate with the module at all. The said they think I have an electrical problem and referred me to another shop. Spoke with Doktor A shortly thereafter and he said I should disregard everything they said -- he doesn't think there's any reason to believe there's an electrical problem.

Anyone have any idea on what I should do next? I've been down for 3 weeks now, and as a full-timer with a full-time job, it's starting to wear on me.
 

Allnunstoport

New member
WDAVI014 I'm at 251k miles and mine just started doing the same thing occasionally. Still not chronic. I'm going to start with code reads and then flush/service the transmission, but I'm all ears if you find the solution.
 

Patrick of M

2005 T1N 2500 (NA spec)
I’ve said it before....if you drop the valve body and clean out the solenoid passages and valves, bad shifts etc can go away. The failure to communicate with the scanner is odd, any chance the scanner is just reporting bad data from the TCM? I.e. the valve tries to shift to 4th gets stuck, TCM say “data from VSS is bad”.
Took me maybe 2 hrs to service the valve body, a dead in the water NAG1 has been working for 2 Yrs since then with zero problems.
 
Last edited:

220629

Well-known member
First.
A swapped in TCM doesn't *require* programming to work, but a dealership would be required to run through the MB recommended adaptation procedure to set shift points and other learned behaviors. The adaption procedure is a programming procedure of a type.

My :2cents:

By the descriptions I read, it appears that the symptoms changed after the first shop swapped out the conductor plate. Not all new parts out of the box are good. Was the part that they installed OEM manufacture or aftermarket?

The question of the shifter module.
I've had no problems so I'm not familiar with all of the shifter module capabilities. The manual gear changing is a basic contact closure. How would the shifter module affect the internal speed sensors that are contained within the transmission? :idunno:

Some info.
The transmission speed monitoring does depend upon the wheel speed sensors for calculation. (The is no output shaft speed monitor. The output shaft speed is calculated/monitored using the differential ratio and the wheel speed data. Just because this hasn't been resolved by a few different shops yet, could the wheel speed calculation/input be involved?

But, I refer back to my new part statement.

:2cents: vic
 

AdrianD

Member
Did it ever flare on the 3-4 shift?
Maybe there's something off in the valvebody (a broken spring, a stuck valve...).
 

wdavi014

'05 2500 140 High Top
I took it to a transmission shop and they said the clutch plates were slipping, so I ended up replacing the transmission with a reman from Silverstar Transmissions for $2800 delivered. Found a shop in Bend, OR who would do the swap for $450 (Darryl Henry's Auto Repair). Contacted many shops in town and they were the only one who would do the work without using their own supplier for a reman. It was much cheaper to do it this way as others wanted $5500 or more. The problem with this approach was that if an issue were to arise after the install, I'd have to pay for labor to find a resolution. THis is because Silverstar's warranty doesn't cover labor, and the shop's warranty only covers issues related to their work, and not those related to a faulty part. Good luck getting the shop to admit any issue is their fault because they'll just toss up their hands and point to a faulty part, and they did.

After the reman tranny went in, it worked for about 8 miles then the same issues returned. Same fault codes. Made me think that they didn't reset the adaptations in the TCM like they said they did. I went back and they reset the TCM in front of me. It worked for another 50 miles, then something very strange happened. In park and neutral, this nasty grinding noise coming from the tranny started. It wasn't present in reverse and drive. 10 hrs later, after being parked for most of that time, the grinding was still their, but when shifting into reverse or drive, the engine stalled and shut off. Let it sit overnight, then the following morning, same issue. Later that day, I tried again but tried something a little different -- I put it in neutral (grinding noise still present), gave it a little gas to raise the RPMs slightly, then shifted into drive, and the engine didn't stall! Also, the grinding went away completely. Could shift through all the modes (P, R, N, and D) normally.

After 2k miles, the issues have not returned I haven't had any real issues except for one: when cold (sitting overnight), the engine does bog down quite a bit when shifting from park to drive. Giving a little fuel prevents it from shutting off, and once I get going, it seems to work normally. Maybe an issue with the reman torque converter?

The good Doktor A advised against replacing it since the issues went away for the most part, which sounded great to me because I didn't want to pay another $450 to replace it again. However, his advice was before the "bogging down" started back up. At this point, my gut says I should expect this tranny to have a premature failure at some point. Really frustrating experience -- living and working full-time in this thing out in the forest without a tranny working for 5 weeks was a real drag.

I ended up buying the AutoEnginuity scan tool so that if/when issues come back, I can read codes, get out of limp mode, reset adaptations on my own and not have to rely on the shop. Gives a little piece of mind.
 

wdavi014

'05 2500 140 High Top
Also, I dropped the pan a couple of weeks ago (2k miles after install) to inspect the fluid and look for metal pieces. These were my observations:
  • No debris to really speak of except for two very small shards (half the size of a grain of rice) of what looked and felt like hard cream-colored plastic. Looked and felt like a small piece of a tooth.
  • Magnet had a little sludge but not bad
  • The fluid didn't look as clear as I thought it would after such low mileage. When swirling the fluid, there were noticeable black fines suspended
 

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