Trans shudder

[DogramTD]

So I searched all the threads and all I found were issues with trans shudder on takeoff and between 1st and 2nd. Mine is under heavy load/power.



Right now I am on a road trip/vacation and twice under heavy load/power pulling a grade the trans made a shudder action. I let it go the first time as the truck trying to tell me something, but then it did it again yesterday as I was pulling the long grade in to the N/E entrance of the Grand Canyon. Any Ideas? Last thing I need is to lose my transmission!

 

[p-Bar]

The common shudder is under light acceleration try pulling the shifter down into one of the manual gears. Sounds like you need a trans shop. If you put your foot into it does it do it??

 

[cerberusiam]

As a guess slipping the TC lockup clutch under power.



Were you in OD at low rpm's on the grade?



Yes, its trying to tell you something, FIX ME.

 

[HBarlow]

My '06 did it and I've read of lots of dually pickups, both Dodge and Furd, doing it when loaded with a heavy fifth wheel that depresses the rear springs. It is caused by placing the center universal joint at a severe angle. You are feeling the rotation of the driveshaft and U joint.

The cure is air bags, Timbrens, longer bump stops on the aux rear springs, or an additional leaf in the rear springs.

It may put severe stress on the U joint but probably won't cause any damage or failure right away.

Enjoy your vacation trip and correct it when you get home.

 

[BGlidewell]

what gear? How may miles on it? Ever had the bands adjusted?

 

[GaryOwen]

A bad driveshaft carrier bearing will give vibration under load. Mine was shuddering at lower speeds (10-30mph) when under load and going uphill. It was fine at higher speeds. I drove it for a couple of thousand miles before I had it repaired.



Are you seeing rpm's increase above normal (slipping)?

 

[ColemanR]

I'm betting torque converter my truck did it under heavy load. I drove it that way for 30k just try not to do it. I just came back from a trip using my son's truck doe's the same thing under heavy load. Just keep the rpm's up will help and know a tran's is in your future. Randy

 

[DogramTD]

It doesnt do it when i bury my foot in it and I am not towing a load, only when I am in a long steep climb and really pouring on the coals, and its only happened twice so far.



I never tow in O/D, only tow in tow/haul mode and always try to keep it from lugging (between 1800-2400 RPM)



The truck is a SWB so I dont have a carrier bearing and I do have Airbags. (even have the cool little compressor mounted under the passenger seat with the controls/guage in the center console. My wife swears she hates it when i turn on the compressor cause it vibrates her seat, but i think she secretly likes it!)



The truck has 54K on it and I had the bands adjusted at about 43K.



One thing to note, I bought the truck used with 27K on it. As I was digging through the glove box I found some paperwork saying that the transmission had been replaced at 24K miles (ah I TRIED TO BY-PASS THE CUSSING FILTER I thought to myself) As I was moving out to Ca from Ut and pulling my trailer, I developed a terrible noise about 5 miles from my final destination that sounded ike the bottom end was ready to come apart. So without tools and a place to work on it, I had it towed to the local dealership where they said the TC bolts had backed out and were hitting the transmission... OUCH! They also told me that I had an aftermarket TC in it which is odd because the invoice for the warranty transmission work was from a dealership. So at this point the piece between my engine and rear end is a mystery to me!

 

[p-Bar]

the torque converter is a weak link on these rams. Some dealers will go outside there party line s and do what is best for the customer. I'm sure the old owner paid for that too. If you have the old receipt call the dealer it was done at they can look it up for you to solve the mystery

 

[cerberusiam]

It doesnt do it when i bury my foot in it and I am not towing a load, only when I am in a long steep climb and really pouring on the coals, and its only happened twice so far.



I never tow in O/D, only tow in tow/haul mode and always try to keep it from lugging (between 1800-2400 RPM)

Unless you have an OD lockout box, you are in OD with the TC locked by 45 mph. The 05 T/H feature was a modified shift program NOT an OD lockout like the previous years.



Given a steep grade, extra power, and low speed you are gonna slip the TC clutch, thats a given. The stock unit will not take heavy loads and the extra power without suffering.



At this point your TC is quite likely on its way out. You only felt it slip once but its a good bet it has started glazing the clutch surface from a little slip all the time. If you actually have a better billet cover TC it may be OK if you fix the pressure problems.



Its also quite likely the direct clutches are glazed and slipping. Without fixing the low line pressures of stock units towing with extra power will eat them and the TC quite fast.



All the above is contigent on the trans NOT having a shift kit which it needs to survive. You will need to run some pressure test to see where line pressures are at, and pull the bottom TC cover to verify it is\isn't a billet TC.

 

[DogramTD]

Thanks Cerberusiam (can i just call you "Cer"?!) I did know it was a modified shift program but I didnt realize that it doesnt lock out the OD anymore. I cant remember if i was in stock "0" or Tow "2" mode at the time of the slip. But I will pull the insp cover when i get home and do some investigating as well as call the dealership who did the work. I have never took the time to learn transmissions so i dont know a whole lot about them. The shift kit increases line pressures right? Is this a change of the entire valve body? Any suggestions (without causing debate!) on where to start on valvebody/shiftkits?

 

[cerberusiam]

Everybody shortens it to Cerb.



If you are looking for better performance and trans life with a little extra power and not lots of power, you do a few simple things without dropping the trans.



The TransGo 48RE shift kits work quite will. It does require dropping and disassembling the VB completely, drilling holes, etc.



Add to the shift kit a billet band strut, billet band anchor, and if you want a billet band apply lever. The first 2 are problem areas the last is a nice to have but usually not a problem with mild mods. These are for the front band. The rear band is usually good until higher performance builds.



You will also need a billet front servo cover with extra seal to help hold the higher pressures.



You will want to remove the drain back valve in the hot cooler line to promote better cooler flow as the shift kit will fix the circulate in park problem and negate the need for the valve.



These will allow you to hold up to 150 extra HP if you drive wisely and make your trans live a lot longer. They can all be done with the trans still in the truck and a one day install.





The TC will be your next replacement item but plan for it and spend the $$ for a good one. When you do it you will need to replace the reaction rings on the pump snout. The rings come with the shift kit so keep them. At the same time it would be a good idea to check the direct and forward clutches and rebuild them.



One word of warning and you have seen the results all ready, the flex plate bolts NEED to be loctited in and with a shift kit and stock TC checking them periodically is good idea. The extra pressure is going to cause the stock TC cover to deform and that loosens the bolts, especially towing. A periodic check until a billet cover TC is installed will save the TC, flex plate, and a tow.

 

[DogramTD]

How would I know if this is already installed when I drop the pan? I would imagine that if the TC is aftermarket they did something w/the VB

 

[p-Bar]

How would I know if this is already installed when I drop the pan? I would imagine that if the TC is aftermarket they did something w/the VB

You would think so as we are told to upgrade both

 

[cerberusiam]

How would I know if this is already installed when I drop the pan? I would imagine that if the TC is aftermarket they did something w/the VB

Not neccessarily, an ugraded TC without any other changes is pretty common. Its a false sense of security but thats all the delaerships seem to want to offer their customers at times.



Its doubtful anything has been done to the VB if it was dealership that did the work, but, sometimes the VB seperator plate is stamped with the name of the kit, like TransGo, Superior, etc, and that can be seen with the pan off. Heavier billet pieces like the band components are easier to see.

 

[MAleshire]

The shudder or slip you are experiencing is most likely the transmission or the TC. If the rpms spike when the shudder occurs, the slippage is most likely in the TC. With no rpm spike the slippage is most likely in the transmission. The problem is not going to get any better. You can gain info by dropping the transmission pan and inspecting any debris in the bottom of the pan or sticking to the magnet, and by looking at and smelling the fluid. Burnt smell and dark color isn't good. A lot of crud/sludge on the bottom of the pan, and small metal filings stuck to the magnet would indicate the transmission is on the way out. Little or no sludge/filing would point to the TC. The way it was explained to me it that the problems you are having are like an avalance. Next problem will most likely be problems with shifting. Starting out in 2nd or 3rd. As the debris piles up in the fluid, valves in the valve body plug up and make shifting problems worse with increased transoil temps and increased parts wear,etc. You should probably start with servicing the transmission to see where you sit. Diagnose what's causing the problem before you throw any money at it. If you end up replacing the trans and/or the TC, spend the money to get one capable of towing the loads you are pulling. Give DTT Performance a call at 866-504-4002 and describe the symptoms. They're really great at answering transmission questions.



Good Luck, Skip

 

[DogramTD]

Well the reason I asked is that I am looking to buy the transgo shift kit. But I guess Ill just have to buy it and drop the pan. If its already there I'll return it. It will only cost me a lot of trans fluid and a big mess! (I hate changing trans fluid!)



Also, the only place I have been able to find any of the other billet parts you speak about is at Welcome to ATF, even so, all I can find there is the intermediate strut.



No one speaks of ATS in here. Is there a reason?

 

[cerberusiam]

Do yourself a favor and drill your pan for a drain before you drop it. You can drill like a 5\16 hole in the passenger side rear corne of the pan and either weld in a bung or get drain kit and put in after its off. Makes for way less mess when you change fluid in the future.



Her is a link for all the parts you need:



PATC 46RE 47RE 48RE Transmissions, Performance Transmission A518, 518



Scroll about 3/4 the way down the page or just search for key words.

 

[DogramTD]

I picked up the billet parts out of Farmboy's Diesel; they sell it in an upgrade kit which was pretty covienient. Is there a good write up somewhere for installation on these billet parts? Im no mechanical rookie but when it comes to transmission's I am!

 

[Yo Hoot]

Here's lookin up... valve body removed. Georend built trans. 4140 steel 1-2 lever
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