Engine/Transmission (1994 - 1998) Shudder when shifting but not TQ shudder

[DonFitzwater]

95 12 valve, auto, 143k miles-original trans. Recently serviced with no debris or burned oil-looked good inside.

Problem is that when torque converter locks up and rpm's are down around 1200, the truck shudders all over like launch shudder. There is literally a small window this happens in and I can control it by not letting rpm's drop down. This does not feel like torque converter shudder I've experienced in my other 12 valves in the past. It's hard to describe but it feels like launch shudder but I'm going too fast for that!

Any ideas?

 

[DonFitzwater]

https://www.turbodieselregister.com...ne-shudder-low-RPM&highlight=governor+shudder

This sounds exactly like what I've got going on.

 

[DonFitzwater]

Ok, did some looking and loosened the governor spring keepers a turn and no change. Tightened the governor spring keepers a turn and no change.

A question for you Bosch pump guys in the know, What is the purpose of the link rod on the side of the pump that looks to be attaching the tps module to the back of the injection pump? Mind is sloppy loose. Just thinking about what in the hell could be causing this......

I'm to the point of pulling the pump off and taking a look see. Hell, if I screw it up, I could always send it out.

 

[DonFitzwater]

I did some more fiddling and found out from Joe G about a TPS mod that allows me to change the lockup points by installing a potentiometer to send a constant voltage to the PCM. I installed a 5K linear potentiometer and hooked it directly to the wires that are normally hooked to the TPS on the side of the injection pump I dialed the voltage up to about 3 on the signal side back to the PCM and she now locks up at a slightly higher rpm and no more shudder at 1250 rpm (because I can now avoid being in that rpm window during lockup!). Problem solved, thanks TDR.