Engine/Transmission (1994 - 1998) low speed shuddering after 4k GSK install

[zilla5.9]

Hello everyone ... I've got a little problem with my GSK install ,maybe someone else experienced the same thing ... my 96 2500 auto normaly runs pretty smooth at just off idle speeds ,,I just installed Piers's 4k GSK and now have a shuddering right when the transmission shifts into 2nd ,If you slowly roll more throttle the shudder gets real bad. Now if i roll hard into the throttle no shudder at all and dont forget to hang on :--) cause she'll move in a hurry... The effect resembles the off idle stumble you get with 370s and too small DV's ... Im kinda stumped ,,I'll probably call Piers tomarrow if i cant figure it out... Thanx in advance. .

 

[BigYellowIron]

Back your Govenor spring adjusting nuts off one click. Sounds like you have them a little to tight.



Adam

 

[JohnE]

<b>z</b>



Did you check the governor lever setting on your fuel plate? Adding a GSK will change the base setting so you may have to adjust there, too. The description really reads as if the lever is diving under the plate in the off idle and then hits the fuel curve as the RPM lifts the lever or if you get on it from the get go.



Another thought is the AFC housing is cocked and binding the governor lever.



If spring tension is a problem I think it is the other way around than Adam described. You probably need to snug the spring tension. It may mean resetting one single side or both sides. I had a problem with flutter (or stumble) when the springs are loose. I noticed no flutter when the springs are tight. The idle did go too high and the throttle action was jumpy, but no flutter with tight springs. I reset them per Piers' verbal instructions and have good throttle action again with no flutter.



I have the 3k springs and #4 plate full BACK. The truck drives better off idle than I thought possible. Now, I need a trany upgrade so I can reset the plate. Then a turbo housing calls to me...



Above all, Talk to Piers!



diesel on

-John

PS sorry for the long post

 

[Diver-Dave]

I have the 3K GSK and noticed the same annoying flutter problem after they were installed. I tried snugging the springs 2 notches last night. The flutter is still there, it just happens at a different speed (47mph instead of 42mph). I also lost a lot of low end responsivness and an increase in idle speed by 300 rpm. I'm going to try Adam's way tomorrow night. I'll post the results then. I'm also thinking that it may be that they're unevenly adjusted.

 

[zilla5.9]

Hello again . . First of all I want to thank every one of the members for all the help !!!!! So far this is what I've found . I tried loosening the spring packs one click each , the flutter seemed to disapear but it actually moved the effect lower down the RPM band but it took the intensity way down. . Tightening the springs moved the effect higher in the RPM band ... Since its almost gone I'll experiment with how balanced the two packs are...
Still tweakin it !!!!!
Thank you again for your help . .

 

[Jim Fulmer]

I'm having the problems with mine too and I'll play with it this weekend, I had Piers send me some 191's and I'll install them and see if it goes away, stock my pump has 181's so I shouldn't have the problem but Piers said if they didn't work to send them back... What a guy! If they don't I'll probably just keep them



Look if you don't remember at the seats, are they flat or step ground. If there old and flat ground Piers has had a few problems like this with those, I also have a few other ideas to try and have moved the tension around like you to move the RPM the stumble happens, right now from the stud to the nut is . 064 clearance and I may see if I can get it one click looser or take it off and pull the thick tiny enter spring out (4K part of it) and see what happens and I'll report back on this thread but it will be Fri or Sat.



Jim

 

[Diver-Dave]

Well I got into it again this morning and backed off the springs 3 notches (after I tightened them yesterday 2 notches). They are pretty loose now. I got my low end responsiveness back and the idle is back to normal (about 700 RPM in gear with A/C on). However the flutter/stumble is still there, maybe even worse.



Jim, I see you've been working on this for a while. I did the 191 DV's and didn't seem to make a difference. I read on one of these threads that after the GSK kit some pumps just stumble while others don't. I can't help but think that it's a result of the combination of the mods many have made. Particularly the GSK, 370's, T/C and maybe timing.



Does anyone think that it might be that one spring may be tightened a notch more than the other?



I go through the top to do the adjustment and I've got it down to 50 minutes. Is there a faster way?



I'd sure like to see one of us work this out. Keep trying and keep posting.

 

[Diver-Dave]

Just another thought on this problem. I don't have the shudder problem when the engine/transmission are cold. It's not until it warms up after about 5-10 minutes that this problem shows up.



Is that the same as with your shuddering problem?



If the problem is tied to the GSK, what might warming up the engine have to do with making this occur? Would the GSK springs be tightening up when hot thereby indicating that looser springs work? Or is it the other way around?... Just some thoughts.

 

[Jim Fulmer]

Dave, mine make no difference in temp, loosening or tightening just move the RPM that the stumble happens around. Hopefully the DV's will get here today or tomorrow and I'll play with it a bit.



Jim

 

[Jim Fulmer]

Ok here goes, got the 191's today and installed them... . bad ass fueling but the stumble is still there, so I called Piers about my ideas... . I loosened the retainers way off and it moved in RPM's but still there so I took the 4k spring out... still there... put if back the way it was then called Piers back, he is doing something different for me and I'm going to R&D it for him so we can learn, it seems as though I have a strange pump so well see if we can learn from it (my pump). My problem is rare, very rare but so is my truck, I will return with answers.



Jim



Jumped on the throttle at 35 MPH tonight and raddled the tires

 

[zilla5.9]

Hello once again ...
I've been doing minor adjustments to my springs ,I started by backing the nuts off until they were flush with the studs . . This is what our local pump tech recomended, while doing so I counted the clicks and found i was about 2 clicks off. The idle quality is really nice but will defuel at about 3200 RPM . I then moved them in one click at a time each until it defueled at about 3800 RPM ,Its a good compromise of idle and high RPM extension ... I still have the stumble but the intensity is lower . I'm going to try adjusting one pack at a time ???