rhythmic vibration before shifts

[z1huggy]

I've got a rhythmic vibration that happens a little before WOT shifts. It almost feels like the car is being held back acceleration wise when it does this. Its a really noticable vibration and it happens before each shift at WOT. I have also noticed the shifts are not firm, thus my next question.
If I drop the pan how can I tell if someone has put a shift kit in it and if not how hard is it to put one in? This something that can it be done in a driveway easily?

Ideally, i'd like to solve the vibration prob first but if one may take care of the other I'm all for it

Thanks

 

[MeanBuicks]

Do you have a scan tool & aftermarket (accurate ) tach? What valve springs are you running?

Reason for asking is transmission problems can sometimes be misdiagnosed tuning problems. It's possible that either you are getting knock retard at the top of each gear, you are hitting your rev limiter or your valve springs are floating. (Factory original springs don't last very long and if you still have 'em, they're shot!)

As far as determining if a kit has been installed, you'll probably have to remove the valve body and separator plate for a look-see. Even then, if you're unfamiliar with these items, you'd have difficulty telling.

Installing a kit is relatively easy as most have well written instructions and illustrations to follow. You should seek out assistance in determining if a kit has already been installed though as one sure fire way to get a transmission confused is to put one kit on top of another.

 

[z1huggy]

I hooked up the Turbolink and got a few strange error codes but not at the time my vibrations are happening. The motor was rebuilt, has approx 50k miles on it, no clue what springs are in there.
I;ve got the caspers knock gauge and I don't see any knock retard. According to my Autometer tach, it shifts outta first at approx 4250rpm from second at about 4500rpm. This right? seems low for a shift point but trannys are like magic to me, dunno squat about autos

Vibrations/shudder? start about at 4000rpms +/- and as the rpms go up get progresssivly stronger.

 

[MeanBuicks]

Do you not feel vibration at part throttle at those rpms or in neutral?

 

[z1huggy]

Holding the trans in second gear at 4k rpms I still get the vibration part throttle or full. Part throttle as it gets close to 4k I can kinda feel them. Car in neutral rev'd to 4k I can feel vibration as well though a steady vibration not the rythmic vibes when WOT.

 

[z1huggy]

I think I'll replace the motor mounts and possibly the tranny mount and see where this leads. From what I've reade the motor mounts should be easy, how hard to replace the trans mount?