driveline vibration part II

[mr plow]

remember i talked about a little launch shudder? Some of you suggested that it may be the clutch packs in the rear limited slip - nope.



Today i had the rear driveshaft balanced ( it was out) and a new centre hangar installed, and still have the shudder. It was determined to be from the transmission - we thin it is the forward drive clutches. basically i need a complete teardown and rebuild. Funny thing is that it has been doing this since i picked up the truck, and it only does this at launch, not turning or in reverse.



should i get this one rebuilt? and if so, shat should i add to it? or should i push for a new replacement (47re)?



any thoughts would be greatly appreciated.



thanks in advance... .





oren.

 

[sag2]

Mr Plow, I think they are barking up the wrong tree. If you refer to the service manual, page 21-140, you should have some other symptom to go with the launch shudder.

In drive, first gear, the rear clutch, and over-running clutches are applied. In the overdrive, the direct and over-running clutches are applied. If you look at the chart, the only suspect part should be the over-running clutch at the rear of the trans. If you want to double check that, pull it into manual low, and if the shudder is gone, it is the over-running clutch, still there, it is most likely something else.

The reason for the above theory is the rear clutch is applied in all forward gears, and the direct and over-running clutches in the over-drive unit are applied in several forward speeds.

By the way, if you are plowing, you should always use manual low to keep from damaging the over-running clutch.

My guess is still the pinion Angle.

 

[mr plow]

pinion angle was checked.

they shimmed it in 1/8 increments as per the manual, and no difference. i trust this shop completely, it is not the stealer, but an outside shop that does nothing else but transmission's and rearends. also it shudders in manual low.





thanks.

 

[llotton]

shudder

Hey Mr plow just a thought, could be the converter, a shudder from the converter might only be felt on launch. Just a thought. By any chance did you change the fluid? and not put in the plus 4?

 

[mr plow]

no such luck...

fluid is original from factory, and plus 4. but thank you.



plow.

 

[mr plow]

quick update...

had the fluid changed alon with the filter in the transmission. the filter was black, and it was loaded with metal/brass pieces and shavings - alot considering there is only about 3500 miles on the truck. truck drives much smoother now, and dealer is going to order me a replacement new transmission.



waiting...