Engine/Transmission (1998.5 - 2002) transmission shudder in O/D??

[Davcruz]

In the last 4-5 weeks I have noticed that as my trucks enters O/D at around 55-65 mph the truck shudders. I can either let off the go pedal or speed up and the shudder goes away. If I am lugging along in O/D and hit an incline it will do the same thing. Again I can accelerate out of it.

2001. 5 2500 CTD in my sig. Has a 48RE transmission rebuilt about 18K ago.

Any ideas?

 

[LBARTLETT]

what kind of rebuild? I'd call them

 

[Regcabguy]

My 47re did just that before the DTT rebuild. Sounds like it's slipping to me.

 

[BlitzkriegSSII]

My truck does the same thing. I see it more in the cold weather. I dont think its the trans because i see the boost needle bouncing when it does it. My truck only does it when its being lugged. If its above around 1500 rpm its fine. It does it really bad in 4X4, I think its from the extra drag. Im thinking its something to do with fuel.



I live in Alaska so we get some really cold times, what kind of weather do you have?



Im running a suncoast trans and it shifts good and firm, so i dont think its that.



What kind of mods do you have done to your truck.

 

[Davcruz]

The transmission is a stock rebuild 48RE.

Mods... .

-Intake
-exhaust
-Edge Comp
-Airdog 100
-Unknown injectors

I thought it was only doing it in O/D, but determined today it does it shifting into 4th also.

Weather here is not cold, maybe in the 30's during the day on cold days.

 

[LBARTLETT]

did you get any warranty with your rebuild? I'd have them look at it, doesn't sound right to me but I never had issues with the 48RE I had in my 04'

 

[Erik@LCD]

Unfortunately, a stock rebuild with any sort of power is a waste. The transmission needs increased line pressure and a better converter to handle even the stock power well. With your mods, a fresh rebuild might have held up if you had done a good converter and valve body (highly recommend Goerend). I would drop the pan and check out the scene. If there isn't too much junk in there, do the VB, Converter and 1-2 lever strap kit (and maybe a laminated flex plate since you are in there). If you do these items, you might get another 50+k out of the guts depending on how you use the truck. If you keep running like you are now, you will be looking at another rebuild AND the stuff mentioned above if you want it to last.

 

[Davcruz]

I actually bought the truck with the rebuilt transmission and most of the mods listed. The transmission warranty expired in May.

So you think this is a transmission problem?

 

[Davcruz]

I should probably add that the trans shifts great and smoothly. Other than the shudder I get it pulls like a freight train. Just doesn't feel like it is slipping.

 

[Erik@LCD]

well, it may just be starting to go. Its likely just the converter having problems

 

[C4gan]

I would agree with Erik... . sounds like the convertor.
I was having similar issues before I put in a Goerend convertor and transgo valve body kit in at 80k. This was the cure and I now have 175k on the stock (knock on wood) trans with just the valve body and convertor upgrade.
Just my thoughts
Chris

 

[Davcruz]

Just back from my trans shop. Looks like Erik et al are correct, the converter is slipping in upper gears and causing the shudder. $2100 to go with a billet converter and go through the trans. Not too bad. Will have to wait until after New Years as he is closed starting Friday.

What about this Transgo valve body, what does that do for me?

 

[C4gan]

The kit will help with the line pressure issue and make the trans shift more positive. I bought the kit for $80. 00 and did it myself in about 1 1/2 hours. I think that it is an inexpensive upgrade to extend the life of the trans. They may have done something like this when they rebuilt the trans.