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Discussion Starter #1 (Edited)
Around 35-40 mph after my trans. shifts in to 2nd, I get a surging type effect. I can't really explain it but under light acceleration once it shifts it feels fine for a moment then seems to lose momentum. Has anybody experienced this? My only mods are a smarty jr. on sw3 Even when I get on it it doesn't seem to put the power to the ground very good. Could it be slipping that bad?
 

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HI,

I have the same thing at that speed on my 2000 3500. Mine jerks a bit and the tach goes up and down by about 50-100 RPM. At first I thought it was a shift sensor that could not make up its mind which gear to stay in. On further review, I think it is the locking torque converter locking and then unlocking. I am not quite sure how to test this theory of mine.

God bless...

Mark
 

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Around 35-40 mph after my trans. shifts in to 2nd, I get a surging type effect. I can't really explain it but under light acceleration once it shifts it feels fine for a moment then seems to momentum. Has anybody experienced this? My only mods are a smarty jr. on sw3 Even when I get on it it doesn't seem to put the power to the ground very good. Could it be slipping that bad?
Same deal on my 05 been told its in need of a band adjusment but in changin out the tranny to a NADP soon so im not goin to bother.
 

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Around 35-40 mph after my trans. shifts in to 2nd, I get a surging type effect. I can't really explain it but under light acceleration once it shifts it feels fine for a moment then seems to momentum. Has anybody experienced this? My only mods are a smarty jr. on sw3 Even when I get on it it doesn't seem to put the power to the ground very good. Could it be slipping that bad?
Probably shuttle shift. Shift kit, shift enhancer, gov pressure solenoid and sensor, or a combination of all will cause this. It gets worse the more power you add.

Yes, you are slipping the TC and probably the direct clutches that bad due to the lack of apply pressure.
 

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HI,

I have the same thing at that speed on my 2000 3500. Mine jerks a bit and the tach goes up and down by about 50-100 RPM. At first I thought it was a shift sensor that could not make up its mind which gear to stay in. On further review, I think it is the locking torque converter locking and then unlocking. I am not quite sure how to test this theory of mine.

God bless...

Mark
Yep, sounds like the infamous TC lock\unlock issue on the 2nd gens.

Here is an easy way to check it out.

1. Find the ground wire from the passenger side battery where it runs past the alternator.

2. Wrap the wire in tin foil over its exposed length.

3. Drive and check it again to see if it changes the issues.
 

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Are you serious, what could that do for it?? My truck does the same thing by the way
 

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Are you serious, what could that do for it?? My truck does the same thing by the way
Pretty strange solution, huh? :lol3: Whats even funnier is it works on the ones that have a TC unlock\unlock problem. :thumbsup

The TC lock\unlock is due to noise on the circuit that controls the TC lockup. The noise spikes interfere with the signal from the APPS that the PCM reads. If the signal is out of range it unlocks the TC which changes the rpm and noise then it locks it again. Usually happens in the 40-55 mph range on the effected trucks. The tin foil blocks the magnetic fields created by the alternator from inducing current spikes into the ground wires and back thru the PCM. There are several other fixes that address the issue also and involve splitting the wiring harness to minimize the noise.

You have to look at the year of trucks to see what the issues might be. The 03 and back trucks have a seperate PCM and wiring that is susceptible to noise. When Dodge combined the functions into the ECU on the block it cured a lot of the APPS\PCM issues.

The 05+ trucks have the combined ECU but also have the ECU controlled TV motor instead of a cable that can be adjusted. Adding power and/or removing TQ management changes the way the power comes and screws up the gov pressure generated by pedal movement. Under light throttle you get shuttle shift and strange lapses in trans wanting to hook up.

A band adjustment will usually make it worse. Even though a shift kit helps a lot, you really need a shift enhancer to advance the TV pressure with less throttle. DTT and TS Performance both market a unit specifically for this. If you run more power\less TM you run a real risk of messing up the direct clutches due to the lack of pressure rise under light throttle.

From personal experience, Smarty on #3 is enough to start the problems on the trans internals. The more of the shuttle and flare shift you get the worse it is for the trans also. :)
 

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Discussion Starter #9 (Edited)
wow, that is some great information. Are an engineer or a technician. So a shift enhancer will help? Would it be benificial to get a vb/tc or go ahead and get a full trans? I have a factory warrenty and an extended warrenty but don't know if they will fix that. Plus a new trans is very spendy. I plan to get a CAI and an aeroturbine 4040xl muffler and an mp-8 pressure box. I am going to have to wait to add big power till I can afford a new trans. so I don't want to drop 2 bills on a TC/VB if I'm going to eventually get a built trans. leaning towards goerend. thanks for all you great input.
 

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So a shift enhancer will help? Would it be benificial to get a vb/tc or go ahead and get a full trans?
A shift enhancer is a must if you are running and kind of TQ management delete. Even a built trans will suffer the shuttle shift under light throttle at times.

A shift kit will help it a lot and get rid of that annoying unhooked feeling of the trans when it can't decide what gear it wants. Together they really make a difference even with a stock TC.

A fully built trans is up to you and your wallet. :lol3: The 48RE is plenty tough enough to handle 600 HP with a little help in parts and some restraint on the skinny pedal. Depends on what you want to spend and do.

A minimum I would do a good low stall single disk TC, billet input, shift kit, billet front band strut, billet front accumulator cover. That will keep things together for a while and can easily be upgraded when needed. :thumbsup
 
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