brian thomas

How's it going guys, I'm new to the game. Have a bad TC shudder when it shifts into overdrive. Transmission was rebuilt by previous owner, and it still has the problem. Checked TPS voltage, was half of what it was supposed to be with key on, tried adjusting it, no increase in voltage. So I installed an electrolytic capacitor in the TPS signal wire close to the PCM. Truck shifts great but no OVERDRIVE, thanks for the help

badme

Do I have this right? The truck did shift into OD but shuttered when it did, now it does not make the shift. If that is correct, does it slip when it wants to make the shift or does it just stay in 3rd gear. Does lockup work? TPS is important for 4th gear shift and lock up. Capacitor will probly have to be removed and you will have to find out why TPS is wrong.

brian thomas

Badme thanks for the reply, Before the capacitor the transmission/TC would have a terrible shudder when the TC locked in forth, always seemed to be around 43-45 MPH, Now when it shifts into third there is no TC lockup, and it dosent even try to shift into forth. Thanks

schoust

Hey Brian I farted around with my Tps like you are doing in an effort to save a few bucks but in the end I shopped around and replaced the thing and the overdrive works great now. Some have good luck with these methods others don't. It may be time to Pony up.......

badme

Fix the tps and make sure to check the fuses and you should have your shifts back. If you are lucky the clutches did not get smoked. When the shifts come back and the tps works right the line preasure should be back up where it belongs and the shudder should go away.

brian thomas

Guys, I replaced the TPS, and removed the capacitor. Truck still shifts into OD at around 45MPH and then almost instant lockup and the truck shaking shudder

schoust

Are you still getting shudder when you hit lock up in Od? If you are at that speed I would think that may be a convertyer problem? I know expert but that does not sound good at 45 mph. I could be wrong though???

badme

Well, you will probly have to do some preasure tests. Go to the local parts store and tell them you want some "Smart Blend" or "Lube Guard" in the red bottle. It works wonders on shutters. If that does not fix the shutter then the preasure guages will have to come out.

brian thomas

Yes, still the shudder, seems really early to me too, It has been driven like this for 20,000 miles, just got the truck.

brian thomas

When I got the truck, I changed fluid and filter with the right stuff, still shuddered, local transmission shop sold me some type of friction modifier, in a small bottle that helped a little bit. The trannsmission shop, that rebuilt the tranny, told the previous owner the "computer" was bad

badme

Wher are you located??

torqueshop

Do you for sure have atf +4 in your Trans? Also was the friction modifier they gave you in a Black bottle from Lube Gard? Lube Gard also make a Red tube of stuff pretty hard to find but it is I think called shutter stop. It is a pretty good pruduct, I know of a couple people it has helped with shudder probs.

Did you check y our TPS voltage at idle position and on the floor

Rare1

I hope you have read all the previous threads for transmission shudder. There is enough here to make a large book.

Some transmission problems can't be solved with chemicals. Internals are not quite right. With your problem since a rebuild I have to say the rebuild was not right. Shops will not admit they don't have the expertise, they like to blame their mistakes on the "computer". Your SHUDDER most likely occured with the original transmission, thus the rebuild. Shudder causes wear to the frictions, and particles build up in the valve orifices causing a restriction to fluid flow, causing poor shifting. If a shop does not completely disassemble and clean everything the problem has not been fixed.

Shudder is slipping in OD lockup, and it is caused by too much power at too low RPM. Your mods make shudder more likely because you get more than stock power at low RPM. Remember that the CTD was depowered by Dodge so that it would not kill the sedan transmission they used. Still, in stock tune, transmissions died because drivers did not keep their RPMs up when they needed power. Even the stock engines needed a stronger transmission, but any power enhancement definately requires a transmission rebuilt to handle more torque at lower RPM.

Once shuddering starts frictions are worn and the particles clog the valves there is no way to fix it without a proper rebuild. With your transmission shuddering for 20,000 miles since rebuild, the rebuild shop and PO did you no favors. You may also have a TPS problem, which clouds the situation and makes diagnosis difficult.

Crimedog

There are TSBs out for this. The problem is with the computer, most likely not the transmission. Every early 2nd gen Dodge that hasn't had the TSB done will lock up the converter at 42MPH. Eventually dodge realized that this was too low and caused shudder and put issued TSBs for it. The 94 trucks required a new computer to fix the problem with a higher lockup point. The 95 trucks were able to be reprogrammed if I remember correctly. I was quoted by Dodge for about $700 for the updated computer. No thanks, I'll just drive around it!

You could install a 3 way manual lockup switch, that way you could manually lock or unlock the converter, but also return it to it's automatic state. There is lots of good reading on the shudder issue over at dodgeram.org

Here is a link to the TSB

schoust

Wow thats big bucks for a job that should have been done right to begin with! How much is it to have them reflash? I need this done on my truck for sure! In three speed mode the lock up comes in early causing this shudder I always thought that my trany had problems until I talked to Dave at Goerand and he told me about the Tsb.