Hi, I am new here; my name is Randy, live about 30 miles Northeast of Atlanta, GA.

The reason for searching and finding this wonderful and informative site is that I am at my wits end with this truck. Apparently the dealer is too, they have recommended that I sell it and get another. Not quite ready to give up just yet, as it still drives and pulls excellent.

It is a 1999 Dodge 3500 Dually Quad Cab 4x2. The transmission was rebuilt by Dodge at 81,000 miles. Purchased this truck at 83,000 miles. The troubles started at 95,000 miles. It currently has 103,000 miles.

Basically, here is what it is doing and the parts that have been replaced to try and correct it.

The transmission shifts in and out of lockup while at a constant speed. Does this at several different speeds, 50mph straight and flat normal driving as well as 70mph going down the interstate. The symptoms are rpm’s fluctuating by about 200-300, and a surging feeling.

It is intermittent, can go for several hundred miles with no problems and all of a sudden it starts doing this again.

It sometimes happens while cruise control is engaged on the interstate; it kicks the cruise off when this happens.

Dealer has tried several different times to diagnose and repair.

It gives a check engine light sometimes and the fault codes are all over the place.

Dealer thinks it is an RFI (radio frequency interference) problem.

Here is a list repairs.

2/19/04 Flashed PCM
3/10/04 Replaced APP Sensor
3/29/04 Replaced Fuel Transfer Pump and Fuel Filter
4/06/04 Replaced Clock Spring and Crankshaft Sensor
4/22/04 Replaced Both Batteries
5/05/04 Replaced Rear ABS Sensor
6/03/04 Replaced Fuel Injector Pump

It now seems to be getting worse, sometimes it is very slow to shift into high gear, the rpm’s get “very” high and it finally does shift. Occasionally while all this is going on, the tachometer now swings more wildly too, can drop down to zero, stay there for a few seconds and then go back to where it should be.

I realize that this post is all over the place, but I am trying to give as much information as possible in hopes that someone recognizes these symptoms and can offer advice.

I will really appreciate any insight that you can give regarding my dilemma. Really hope that the advice that I get here is not the same as the dealers “sell the truck”

Thanks in advance,
Randy

 

Sounds to me like the dealer has no clue about what to look for. The first thought I had was the torque convertor. I have had problems with one in a truck I used to own, and it displayed the surging/flucuating problems to the letter.

For some reason, I keep thinking about the speed sensor, but not sure why

HTH, but for sure some more folks will jump into this with you.

KEEP the truck, it is just now getting broke in good.

Ed

 

I found this reply in another forum complaining of a similar problem:

(Sounds like the same old problem of electrical noise spikes, Cleaning the battery terminals is a temporary fix. I fought this problem for over a year and finally fixed it with a DTT noise filter.

Call DTT 1 866 504 4002)







Another option that I thought of is a misadjusted brake light switch. The torque converter and cruise are both tied to the brake light switch so that if you apply the brakes, the cruise will kick off and also so the torque converter unlocks for stopping. If the switch is being tripped when it should not be, it will kick out the cruise and/or cause the torque converter to unlock/lock.

Good Luck

 

I second the idea of the noise filter- and I thijnk it will prove worthwhile to check the cable loom to the PCM for bad contacts too. I'd go over each and every connector you can find with a good contact cleaner and dielectric grease. Most dealers do diagnose by the 'puter and replace sensors even when it's the wires to the sensor being bad. The tach fluttering and falling don indicate a crankshaft position sensor.(Or the wiring to it)
Do you get any codes? (Cycle key off on off on off on- read codes from odometer)

HTH

AlpineRAM

 

First, let me say thanks for the replies. These all sound like good ideas, I have never heard of the DTT noise suppression device, will definitely look into getting one of those. Are they difficult to install?

Will start checking and cleaning connections too.

The brake light idea has me thinking, have a used brake controller that I got from a friend…need to check with him to see when we installed that, the timing could be very coincidental…think it will get disconnected today just for good measure…

Anyway, had some more “interesting” symptoms arise yesterday. Thought I would share those here also in hopes that it may help with a diagnosis.

We had to go 70 miles to the other side of Atlanta. The first 45 miles consisted of the usual lock/unlock issues. Around mile 45 it really started to act up. It downshifted to 3rd gear and was taching very high, really couldn’t travel much faster than 50-55mph, it would not shift back into 4th. This continued for the remainder of the trip.

The tachometer then started to fluctuate wildly…going from peg to peg. And strangely enough the air conditioner stopped cooling.

Luckily it was time to get off the interstate. We had approximately five miles left to our destination with several traffic lights along the way. While stopped at a couple of the lights, with the tach still swinging wildly, the truck sounded as though it wanted to stop running (almost like it wasn’t getting a steady stream of fuel). It actually did stall at one light and was stubborn to get it going again.

We were at our destination for about 3 hours.

Got in the truck, fired it up and traveled the entire 70 miles home without incidence. The truck drove like new. No tach issues, no lockup issues, the air conditioner was icy cold.

It is so very frustrating.

Thanks again for all the replies. Will let you know how things progress.
Randy

 

I think all of this points to a wiring problem. (Maybe even the contacts in a connector)
If the electronics don't know the rpm they'll have to do very wild guesses about which gear is appropriate. And with everything out of range the AC will also be turned off fo safety. The 24V uses the crankshaft position sensor to determine inj. timing, rpm (important for the idle) and shifting gears (OD and lockup operation only)- and for showing you the tach. If somebody installed a brake controller and harmed eg a ground connector or even used one of the CAN-Bus grounds for brake controller ground it's clear why it acts up like that.
The DTT noise filter can be found on their website. www.dieseltrans.com
The install is actually very easy. (Splicing into 2 wires, including instructions)
But I'd check out the cause for the swinging tach etc first- the noise filter won't help on that one.

AlpineRAM

 

to update this topic, have ordered the DTT noise filter, will let you all know how that works out.

had a rather sizable fuel leak, assumed it was from one of the connections from the fuel injector pump the dealer replaced last week. it wasn't, it was from the top of the fuel filter, have asked about that in a separate post.

anyway, while at the dealer getting the leak checked the mechanic checked the codes for the "check engine" light AGAIN...the codes came up as a bad crankshaft position sensor and bad cam position sensor...the crankshaft sensor was already replaced on 4/6/04, they are going to replace again...

he also said that something new was showing up, that the "Bus" had completely died at some point...not sure what that means but thought that this along with the other information that I have posted before may spark some other ideas here.

Thanks again for everyone's help and patience,
Randy

 

I think this guy refers to the can-bus. All the infos are exchanged between the modules via this bus. If the bus goes down the single modules won't be able to function properly. (not knowing the situation means not knowing how to react). In some cases a bad sensor shorting to ground can make the bus collapse leading to the results you have now.

Just my 2c

AlpineRAM

 

Not sure about the other electronic problems your having but I have a 98.5 24v also that the trans did very similar things as yours and was intermitant. After many trips to the dealer with no luck, one time I drove the truck while the mechanic watched the computer he noticed the sensor on the output shaft would intermitantly read 0 causing the converter to unlock. Maybe yours is acting up as well? One interesting thing is the part # for the output sensor is the same for a Caravan and its a very common problem in the vans Anyhow just thought this may help.

 

Any time the tach is irratic, its possibly the engine speed sensor.Ratsun is correct the input and output sensors on the trans are known for problems.They are also cheap and easy to install.Eliminate them as a possible problem.Merv

 

i had the dealer change the oil and filter yesterday and as soon as i left there it start to go back and forth from third to fourth if you were not accellerating,like it couldn't make up its mind third or od. isthere something by the oil filter that they could have got oil on. is there a contection somewhere to clean.were is the tps and pcm.

 

The connector at the sensor has two female spades that slide over the pins of the crank sensor those spades can spread and not connect tightly onto the pins of the sensor.Take a fine dental like tool and lightly pry the spades so the connection is tighted. Merv

 

huff where is that crank sensor at?

 

Behind the starter where the dip stick enters the block.To get access it might be easier to pull the starter. Merv

 

Thanks SO much to everyone!!!! I love my truck again!!!! The $37 part from DTT seems to have cured the problem. Installed it last week and just got back from a 1200 mile road trip, it did not act up at all.

Man, I am one happy camper!!

The dealer attempted to fix this problem for over five months by throwing various parts at it.....nothing worked....they even advised me to sell the truck....there are some things in life that I will never understand.

Thanks again to you all!!!!