Transmission Shudder question

[65-f100]

Need a little help. Have a 96 K2500 Suburban with approx. 180k miles. I notice after extended highway driving 2-3 hours - if I come to a stop like at a interstate exit ramp - when I start again the transmission seems to shudder briefly. After it shifts, there are no problems and it usually will not do it again. Just fyi - I recently had the trans. flushed and new filter and fluid. The "shudder" occured before the flush and still does it. No other problems, no burnt fluid, etc. I almost feels like the TCC is not fully disengaging - but the engine is not lugging at idle or showing any other signs that the TCC is engaged. Any ideas?

[Barry Nave]

Could be low pump psi on trany.
I installed an Auto-Trans Inceptor that plugs into the Elect. conection at the trans.
It will rasie line psi and TCC lock up.
JK sells this,also his chip will do the same.

[HowieE]

If the shutter is only on startup after a full stop it is not related to the TCC. The TCC is only engaged at speeds above 50mph.
Is this only in 1st. gear or does it shutter at first engagement of each gear as you upshift.

I have a shutter just as the transmission drops out of TCC lockup at 50 mph under some load conditions. This happens while pulling a hill and the truck is slowing down as I am appling throttle. In this case it appears that some combiation of road speed, throttle position the PCM applies and unapplies the TCC in rapid order.

[DURAMAXX]

Try this. I had the same problem with my Burbs Tranny 4l80E. Worked for me and the cost is cheap. Plus it is good maintenance. Good luck Thomas
http://www.lucasoil.com/Product_Details.cfm?Product_ID=12

[1bad383]

try cleaning the speed sensors, both of them. Located on the drivers side with the electrical connectors on them. If they are coated with some fuzz they can create all kinds of havoc. Good luck

[65-f100]

HowieE - It's only in 1st gear right as I begin to accelerate. It's goes away after the 1-2 shift and doesn't come back. Kinda strange. I'll check the speed sensors as suggested and may try some additive as well to see what happens. Thanks for the input.

[65turboman]

65f-100, I had a bad U-joint that caused a shudder while taking off in first gear. I never noticed the vibration after upshifting to 2nd though.
Good luck.
_____________________________
1995 Reg. Cab 2500 6.5TD

[DURAMAXX]

Do one fix at a time so you know what works on the shudder. smile.gif

Thomas

[MJEasly]

What kind of rear differential do you have? My 99 K2500 Sub with the limited slip shutters a bit after driving on the highway for any amount of time. My guess is the weights are getting stuck to the housing during the drive and are "broken" free at the first stoplight. Normal operation afterward.

[Fshmn62]

My 98 Sub does same thing suspect something to do with limited slip I think

[G. Gearloose]

I concur with MJEasly..

[HowieE]

Now that you mwntion it my 97 has started to give a slight shutter on start up only if I am turning right during the start up. This only lasts for a second.

[65-f100]

The limited slip may be the deal. HowieE - I also notice mine mostly when turning right at start-up. I have not changed diff fluid so I may try that as well. I'll do one at a time and see if I can isolate it. I'll let y'all know what I find out. Thanks for the good info.