DaveX

My car (99Z) has a pretty bad vibration in the drivetrain that occurs in 3rd and 4th, right after the converter locks up when under a moderate load. It started shortly after I installed the converter and I'm pretty sure it is the problem. Is there anything I can do to eliminate or at least cut down on the vibration without having to replace it with something else? Tuning perhaps? I have EFI live but have only changed the shift points a little and cut back on the tm. I really don't want to have to take it back out. My car has 41k on it and the converter has only been in for maybe 5k miles.

Gilbert@Ace Racing

How long have you been feeling the "vibration"? I am concerned that the converter clutch is slipping.

Can you tell me what your converter apply and release parameters are"?

g

kaos_

iTrader: (12)

i think i'm feeling the same thing but it's been happening consistently, as though it isn't a problem. when it goes in to overdrive it just feels real shaky and rough, especially at low rpm. i hate overdrive! is this just because i have a TCI and not a yank?

Gilbert@Ace Racing

Good question.... it could easily be the converter clutch that has failed /is slipping.

It could easily be a tuning issue as well... at slower speeds these cars will go in to a cam surge when locked up, which could damage the clutch material. But hey, at the end of the day it really needs to be diagnosed by soemone who understands these F-bodies!

Feel free to call me tomorrow and I'll see what I can do to help you determine which way to go.

g

DaveX

I think so. I'm still learning my way around the software though. Are you asking for the TCC Apply and Release speeds? Or is it something else?

I installed the converter 2 years ago, but have only driven the car 4k miles since. It's been doing it all along, but seem worse since I went from 2.73 to 3.42 gears which was just a few days ago.

Thanks for your help

Gilbert@Ace Racing

Ok... I believe that the symptom you are experiencing is related to the converter itself. What is the fluid condition?

yes, for each gear.

g

DaveX

APPLY - 2nd
LABELS Gear mode
TPS % {link: SAE.TP} Normal
0 204.36
6.25 204.36
12.5 204.36
18.75 204.36
25 204.36
31.25 204.36
37.5 204.36
43.75 204.36
50 204.36
56.25 204.36
62.5 204.36
68.75 204.36
75 204.36
81.25 204.36
87.5 204.36
93.75 204.36
100 204.36

APPLY - 3RD
LABELS Gear mode
TPS % {link: SAE.TP} Normal
0 24.80
6.25 24.80
12.5 27.78
18.75 33.53
25 41.91
31.25 48.61
37.5 54.48
43.75 83.82
50 204.36
56.25 204.36
62.5 204.36
68.75 204.36
75 204.36
81.25 204.36
87.5 204.36
93.75 204.36
100 204.36

APPLY - 4TH
LABELS Gear mode
TPS % {link: SAE.TP} Normal
0 35.92
6.25 35.92
12.5 35.92
18.75 38.32
25 39.12
31.25 39.12
37.5 39.12
43.75 39.12
50 39.12
56.25 39.12
62.5 39.12
68.75 39.12
75 39.12
81.25 203.57
87.5 203.57
93.75 203.57
100 203.57

DaveX

RELEASE - 2ND
LABELS Gear mode
TPS % {link: SAE.TP} Normal
0 204.36
6.25 204.36
12.5 204.36
18.75 204.36
25 204.36
31.25 204.36
37.5 204.36
43.75 204.36
50 204.36
56.25 204.36
62.5 204.36
68.75 204.36
75 204.36
81.25 204.36
87.5 204.36
93.75 204.36
100 204.36

RELEASE - 3RD
LABELS Gear mode
TPS % {link: SAE.TP} Normal
0 22.75
6.25 22.75
12.5 22.75
18.75 22.75
25 25.55
31.25 27.14
37.5 28.74
43.75 30.34
50 32.73
56.25 35.13
62.5 39.91
68.75 48.70
75 62.27
81.25 74.24
87.5 203.57
93.75 203.57
100 203.57

RELEASE - 4TH
LABELS Gear mode
TPS % {link: SAE.TP} Normal
0 32.73
6.25 32.73
12.5 32.73
18.75 32.73
25 35.92
31.25 37.52
37.5 37.52
43.75 37.52
50 37.52
56.25 37.52
62.5 37.52
68.75 37.52
75 37.52
81.25 37.52
87.5 203.57
93.75 203.57
100 203.57

DaveX

Lots of numbers. I'm not having any trouble with it locking up or hunting for a gear. It just vibrates when under a moderate load just after locking up. Under a light load, all is fine. Also, all the fluid was replaced at the time I installed it. So it only has 4k miles on it. I used Dexron II. I do not have a shift kit btw. Any advice appreciated.

1fastz

iTrader: (16)

a buddy of mine had the same problem with his ride after he had the converter installed. he had the stall for months and then it started shaking/vibrating when it was in high gear and he would tap the gas. it only vibrated on the freeway but occastionaly sometime when cruising but it seemed to happen more when it was in overdrive though. We thought it was the driveline that needed to be rebalanced but he ended up getting a new converter anyways and when we slapped that one in, the shaking just went away..... So im guessing its the converter, just my .02